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diff --git a/share/info/ld.info b/share/info/ld.info index ac12b21..b03a430 100644 --- a/share/info/ld.info +++ b/share/info/ld.info @@ -1,13 +1,6 @@ -This is ld.info, produced by makeinfo version 4.13 from -/mnt/jenkins/workspace/linaro-android_toolchain64-4.9-2014.09/build/objdir/../build/../binutils/binutils-current/ld/ld.texinfo. +This is ld.info, produced by makeinfo version 5.1 from ld.texinfo. -INFO-DIR-SECTION Software development -START-INFO-DIR-ENTRY -* Ld: (ld). The GNU linker. -END-INFO-DIR-ENTRY - - This file documents the GNU linker LD (Linux/GNU Binutils) version -2.23.52.0.2. +This file documents the GNU linker LD (GNU Binutils) version 2.24.0. Copyright (C) 1991-2013 Free Software Foundation, Inc. @@ -17,6 +10,10 @@ any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License". +INFO-DIR-SECTION Software development +START-INFO-DIR-ENTRY +* Ld: (ld). The GNU linker. +END-INFO-DIR-ENTRY File: ld.info, Node: Top, Next: Overview, Up: (dir) @@ -24,21 +21,18 @@ File: ld.info, Node: Top, Next: Overview, Up: (dir) LD ** -This file documents the GNU linker ld (Linux/GNU Binutils) version -2.23.52.0.2. +This file documents the GNU linker ld (GNU Binutils) version 2.24.0. This document is distributed under the terms of the GNU Free -Documentation License version 1.3. A copy of the license is included -in the section entitled "GNU Free Documentation License". +Documentation License version 1.3. A copy of the license is included in +the section entitled "GNU Free Documentation License". * Menu: * Overview:: Overview * Invocation:: Invocation * Scripts:: Linker Scripts - * Machine Dependent:: Machine Dependent Features - * BFD:: BFD * Reporting Bugs:: Reporting Bugs @@ -52,24 +46,24 @@ File: ld.info, Node: Overview, Next: Invocation, Prev: Top, Up: Top 1 Overview ********** -`ld' combines a number of object and archive files, relocates their -data and ties up symbol references. Usually the last step in compiling -a program is to run `ld'. +'ld' combines a number of object and archive files, relocates their data +and ties up symbol references. Usually the last step in compiling a +program is to run 'ld'. - `ld' accepts Linker Command Language files written in a superset of + 'ld' accepts Linker Command Language files written in a superset of AT&T's Link Editor Command Language syntax, to provide explicit and total control over the linking process. - This version of `ld' uses the general purpose BFD libraries to -operate on object files. This allows `ld' to read, combine, and write -object files in many different formats--for example, COFF or `a.out'. + This version of 'ld' uses the general purpose BFD libraries to +operate on object files. This allows 'ld' to read, combine, and write +object files in many different formats--for example, COFF or 'a.out'. Different formats may be linked together to produce any available kind of object file. *Note BFD::, for more information. Aside from its flexibility, the GNU linker is more helpful than other linkers in providing diagnostic information. Many linkers abandon execution immediately upon encountering an error; whenever possible, -`ld' continues executing, allowing you to identify other errors (or, in +'ld' continues executing, allowing you to identify other errors (or, in some cases, to get an output file in spite of the error). @@ -78,7 +72,7 @@ File: ld.info, Node: Invocation, Next: Scripts, Prev: Overview, Up: Top 2 Invocation ************ -The GNU linker `ld' is meant to cover a broad range of situations, and +The GNU linker 'ld' is meant to cover a broad range of situations, and to be as compatible as possible with other linkers. As a result, you have many choices to control its behavior. @@ -93,22 +87,22 @@ File: ld.info, Node: Options, Next: Environment, Up: Invocation 2.1 Command Line Options ======================== - The linker supports a plethora of command-line options, but in actual +The linker supports a plethora of command-line options, but in actual practice few of them are used in any particular context. For instance, -a frequent use of `ld' is to link standard Unix object files on a +a frequent use of 'ld' is to link standard Unix object files on a standard, supported Unix system. On such a system, to link a file -`hello.o': +'hello.o': ld -o OUTPUT /lib/crt0.o hello.o -lc - This tells `ld' to produce a file called OUTPUT as the result of -linking the file `/lib/crt0.o' with `hello.o' and the library `libc.a', + This tells 'ld' to produce a file called OUTPUT as the result of +linking the file '/lib/crt0.o' with 'hello.o' and the library 'libc.a', which will come from the standard search directories. (See the -discussion of the `-l' option below.) +discussion of the '-l' option below.) - Some of the command-line options to `ld' may be specified at any + Some of the command-line options to 'ld' may be specified at any point in the command line. However, options which refer to files, such -as `-l' or `-T', cause the file to be read at the point at which the +as '-l' or '-T', cause the file to be read at the point at which the option appears in the command line, relative to the object files and other file options. Repeating non-file options with a different argument will either have no further effect, or override prior @@ -122,22 +116,22 @@ command-line options, except that an object file argument may not be placed between an option and its argument. Usually the linker is invoked with at least one object file, but you -can specify other forms of binary input files using `-l', `-R', and the +can specify other forms of binary input files using '-l', '-R', and the script command language. If _no_ binary input files at all are specified, the linker does not produce any output, and issues the -message `No input files'. +message 'No input files'. If the linker cannot recognize the format of an object file, it will assume that it is a linker script. A script specified in this way augments the main linker script used for the link (either the default -linker script or the one specified by using `-T'). This feature -permits the linker to link against a file which appears to be an object -or an archive, but actually merely defines some symbol values, or uses -`INPUT' or `GROUP' to load other objects. Specifying a script in this -way merely augments the main linker script, with the extra commands -placed after the main script; use the `-T' option to replace the -default linker script entirely, but note the effect of the `INSERT' -command. *Note Scripts::. +linker script or the one specified by using '-T'). This feature permits +the linker to link against a file which appears to be an object or an +archive, but actually merely defines some symbol values, or uses 'INPUT' +or 'GROUP' to load other objects. Specifying a script in this way +merely augments the main linker script, with the extra commands placed +after the main script; use the '-T' option to replace the default linker +script entirely, but note the effect of the 'INSERT' command. *Note +Scripts::. For options whose names are a single letter, option arguments must either follow the option letter without intervening whitespace, or be @@ -145,22 +139,22 @@ given as separate arguments immediately following the option that requires them. For options whose names are multiple letters, either one dash or two -can precede the option name; for example, `-trace-symbol' and -`--trace-symbol' are equivalent. Note--there is one exception to this -rule. Multiple letter options that start with a lower case 'o' can -only be preceded by two dashes. This is to reduce confusion with the -`-o' option. So for example `-omagic' sets the output file name to -`magic' whereas `--omagic' sets the NMAGIC flag on the output. +can precede the option name; for example, '-trace-symbol' and +'--trace-symbol' are equivalent. Note--there is one exception to this +rule. Multiple letter options that start with a lower case 'o' can only +be preceded by two dashes. This is to reduce confusion with the '-o' +option. So for example '-omagic' sets the output file name to 'magic' +whereas '--omagic' sets the NMAGIC flag on the output. Arguments to multiple-letter options must either be separated from the option name by an equals sign, or be given as separate arguments immediately following the option that requires them. For example, -`--trace-symbol foo' and `--trace-symbol=foo' are equivalent. Unique +'--trace-symbol foo' and '--trace-symbol=foo' are equivalent. Unique abbreviations of the names of multiple-letter options are accepted. Note--if the linker is being invoked indirectly, via a compiler -driver (e.g. `gcc') then all the linker command line options should be -prefixed by `-Wl,' (or whatever is appropriate for the particular +driver (e.g. 'gcc') then all the linker command line options should be +prefixed by '-Wl,' (or whatever is appropriate for the particular compiler driver) like this: gcc -Wl,--start-group foo.o bar.o -Wl,--end-group @@ -178,172 +172,171 @@ the joined forms of both single- and multiple-letter options, such as: Here is a table of the generic command line switches accepted by the GNU linker: -`@FILE' - Read command-line options from FILE. The options read are - inserted in place of the original @FILE option. If FILE does not - exist, or cannot be read, then the option will be treated - literally, and not removed. +'@FILE' + Read command-line options from FILE. The options read are inserted + in place of the original @FILE option. If FILE does not exist, or + cannot be read, then the option will be treated literally, and not + removed. Options in FILE are separated by whitespace. A whitespace character may be included in an option by surrounding the entire - option in either single or double quotes. Any character - (including a backslash) may be included by prefixing the character - to be included with a backslash. The FILE may itself contain - additional @FILE options; any such options will be processed - recursively. + option in either single or double quotes. Any character (including + a backslash) may be included by prefixing the character to be + included with a backslash. The FILE may itself contain additional + @FILE options; any such options will be processed recursively. -`-a KEYWORD' +'-a KEYWORD' This option is supported for HP/UX compatibility. The KEYWORD - argument must be one of the strings `archive', `shared', or - `default'. `-aarchive' is functionally equivalent to `-Bstatic', + argument must be one of the strings 'archive', 'shared', or + 'default'. '-aarchive' is functionally equivalent to '-Bstatic', and the other two keywords are functionally equivalent to - `-Bdynamic'. This option may be used any number of times. + '-Bdynamic'. This option may be used any number of times. -`--audit AUDITLIB' - Adds AUDITLIB to the `DT_AUDIT' entry of the dynamic section. +'--audit AUDITLIB' + Adds AUDITLIB to the 'DT_AUDIT' entry of the dynamic section. AUDITLIB is not checked for existence, nor will it use the DT_SONAME specified in the library. If specified multiple times - `DT_AUDIT' will contain a colon separated list of audit interfaces - to use. If the linker finds an object with an audit entry while + 'DT_AUDIT' will contain a colon separated list of audit interfaces + to use. If the linker finds an object with an audit entry while searching for shared libraries, it will add a corresponding - `DT_DEPAUDIT' entry in the output file. This option is only + 'DT_DEPAUDIT' entry in the output file. This option is only meaningful on ELF platforms supporting the rtld-audit interface. -`-A ARCHITECTURE' -`--architecture=ARCHITECTURE' - In the current release of `ld', this option is useful only for the - Intel 960 family of architectures. In that `ld' configuration, the - ARCHITECTURE argument identifies the particular architecture in - the 960 family, enabling some safeguards and modifying the - archive-library search path. *Note `ld' and the Intel 960 family: +'-A ARCHITECTURE' +'--architecture=ARCHITECTURE' + In the current release of 'ld', this option is useful only for the + Intel 960 family of architectures. In that 'ld' configuration, the + ARCHITECTURE argument identifies the particular architecture in the + 960 family, enabling some safeguards and modifying the + archive-library search path. *Note 'ld' and the Intel 960 family: i960, for details. - Future releases of `ld' may support similar functionality for - other architecture families. + Future releases of 'ld' may support similar functionality for other + architecture families. -`-b INPUT-FORMAT' -`--format=INPUT-FORMAT' - `ld' may be configured to support more than one kind of object - file. If your `ld' is configured this way, you can use the `-b' +'-b INPUT-FORMAT' +'--format=INPUT-FORMAT' + 'ld' may be configured to support more than one kind of object + file. If your 'ld' is configured this way, you can use the '-b' option to specify the binary format for input object files that - follow this option on the command line. Even when `ld' is - configured to support alternative object formats, you don't - usually need to specify this, as `ld' should be configured to - expect as a default input format the most usual format on each - machine. INPUT-FORMAT is a text string, the name of a particular - format supported by the BFD libraries. (You can list the - available binary formats with `objdump -i'.) *Note BFD::. + follow this option on the command line. Even when 'ld' is + configured to support alternative object formats, you don't usually + need to specify this, as 'ld' should be configured to expect as a + default input format the most usual format on each machine. + INPUT-FORMAT is a text string, the name of a particular format + supported by the BFD libraries. (You can list the available binary + formats with 'objdump -i'.) *Note BFD::. You may want to use this option if you are linking files with an - unusual binary format. You can also use `-b' to switch formats + unusual binary format. You can also use '-b' to switch formats explicitly (when linking object files of different formats), by - including `-b INPUT-FORMAT' before each group of object files in a + including '-b INPUT-FORMAT' before each group of object files in a particular format. The default format is taken from the environment variable - `GNUTARGET'. *Note Environment::. You can also define the input - format from a script, using the command `TARGET'; see *note Format + 'GNUTARGET'. *Note Environment::. You can also define the input + format from a script, using the command 'TARGET'; see *note Format Commands::. -`-c MRI-COMMANDFILE' -`--mri-script=MRI-COMMANDFILE' - For compatibility with linkers produced by MRI, `ld' accepts script +'-c MRI-COMMANDFILE' +'--mri-script=MRI-COMMANDFILE' + For compatibility with linkers produced by MRI, 'ld' accepts script files written in an alternate, restricted command language, - described in *note MRI Compatible Script Files: MRI. Introduce - MRI script files with the option `-c'; use the `-T' option to run - linker scripts written in the general-purpose `ld' scripting - language. If MRI-CMDFILE does not exist, `ld' looks for it in the - directories specified by any `-L' options. - -`-d' -`-dc' -`-dp' + described in *note MRI Compatible Script Files: MRI. Introduce MRI + script files with the option '-c'; use the '-T' option to run + linker scripts written in the general-purpose 'ld' scripting + language. If MRI-CMDFILE does not exist, 'ld' looks for it in the + directories specified by any '-L' options. + +'-d' +'-dc' +'-dp' These three options are equivalent; multiple forms are supported for compatibility with other linkers. They assign space to common - symbols even if a relocatable output file is specified (with - `-r'). The script command `FORCE_COMMON_ALLOCATION' has the same - effect. *Note Miscellaneous Commands::. + symbols even if a relocatable output file is specified (with '-r'). + The script command 'FORCE_COMMON_ALLOCATION' has the same effect. + *Note Miscellaneous Commands::. -`--depaudit AUDITLIB' -`-P AUDITLIB' - Adds AUDITLIB to the `DT_DEPAUDIT' entry of the dynamic section. +'--depaudit AUDITLIB' +'-P AUDITLIB' + Adds AUDITLIB to the 'DT_DEPAUDIT' entry of the dynamic section. AUDITLIB is not checked for existence, nor will it use the DT_SONAME specified in the library. If specified multiple times - `DT_DEPAUDIT' will contain a colon separated list of audit - interfaces to use. This option is only meaningful on ELF - platforms supporting the rtld-audit interface. The -P option is - provided for Solaris compatibility. + 'DT_DEPAUDIT' will contain a colon separated list of audit + interfaces to use. This option is only meaningful on ELF platforms + supporting the rtld-audit interface. The -P option is provided for + Solaris compatibility. -`-e ENTRY' -`--entry=ENTRY' +'-e ENTRY' +'--entry=ENTRY' Use ENTRY as the explicit symbol for beginning execution of your program, rather than the default entry point. If there is no symbol named ENTRY, the linker will try to parse ENTRY as a number, and use that as the entry address (the number will be interpreted - in base 10; you may use a leading `0x' for base 16, or a leading - `0' for base 8). *Note Entry Point::, for a discussion of defaults + in base 10; you may use a leading '0x' for base 16, or a leading + '0' for base 8). *Note Entry Point::, for a discussion of defaults and other ways of specifying the entry point. -`--exclude-libs LIB,LIB,...' - Specifies a list of archive libraries from which symbols should - not be automatically exported. The library names may be delimited - by commas or colons. Specifying `--exclude-libs ALL' excludes - symbols in all archive libraries from automatic export. This - option is available only for the i386 PE targeted port of the - linker and for ELF targeted ports. For i386 PE, symbols - explicitly listed in a .def file are still exported, regardless of - this option. For ELF targeted ports, symbols affected by this - option will be treated as hidden. - -`--exclude-modules-for-implib MODULE,MODULE,...' +'--exclude-libs LIB,LIB,...' + Specifies a list of archive libraries from which symbols should not + be automatically exported. The library names may be delimited by + commas or colons. Specifying '--exclude-libs ALL' excludes symbols + in all archive libraries from automatic export. This option is + available only for the i386 PE targeted port of the linker and for + ELF targeted ports. For i386 PE, symbols explicitly listed in a + .def file are still exported, regardless of this option. For ELF + targeted ports, symbols affected by this option will be treated as + hidden. + +'--exclude-modules-for-implib MODULE,MODULE,...' Specifies a list of object files or archive members, from which symbols should not be automatically exported, but which should be - copied wholesale into the import library being generated during - the link. The module names may be delimited by commas or colons, - and must match exactly the filenames used by `ld' to open the - files; for archive members, this is simply the member name, but - for object files the name listed must include and match precisely - any path used to specify the input file on the linker's - command-line. This option is available only for the i386 PE - targeted port of the linker. Symbols explicitly listed in a .def - file are still exported, regardless of this option. - -`-E' -`--export-dynamic' -`--no-export-dynamic' - When creating a dynamically linked executable, using the `-E' - option or the `--export-dynamic' option causes the linker to add + copied wholesale into the import library being generated during the + link. The module names may be delimited by commas or colons, and + must match exactly the filenames used by 'ld' to open the files; + for archive members, this is simply the member name, but for object + files the name listed must include and match precisely any path + used to specify the input file on the linker's command-line. This + option is available only for the i386 PE targeted port of the + linker. Symbols explicitly listed in a .def file are still + exported, regardless of this option. + +'-E' +'--export-dynamic' +'--no-export-dynamic' + When creating a dynamically linked executable, using the '-E' + option or the '--export-dynamic' option causes the linker to add all symbols to the dynamic symbol table. The dynamic symbol table - is the set of symbols which are visible from dynamic objects at - run time. + is the set of symbols which are visible from dynamic objects at run + time. If you do not use either of these options (or use the - `--no-export-dynamic' option to restore the default behavior), the - dynamic symbol table will normally contain only those symbols - which are referenced by some dynamic object mentioned in the link. + '--no-export-dynamic' option to restore the default behavior), the + dynamic symbol table will normally contain only those symbols which + are referenced by some dynamic object mentioned in the link. - If you use `dlopen' to load a dynamic object which needs to refer + If you use 'dlopen' to load a dynamic object which needs to refer back to the symbols defined by the program, rather than some other dynamic object, then you will probably need to use this option when linking the program itself. - You can also use the dynamic list to control what symbols should - be added to the dynamic symbol table if the output format supports - it. See the description of `--dynamic-list'. + You can also use the dynamic list to control what symbols should be + added to the dynamic symbol table if the output format supports it. + See the description of '--dynamic-list'. Note that this option is specific to ELF targeted ports. PE - targets support a similar function to export all symbols from a - DLL or EXE; see the description of `--export-all-symbols' below. + targets support a similar function to export all symbols from a DLL + or EXE; see the description of '--export-all-symbols' below. -`-EB' +'-EB' Link big-endian objects. This affects the default output format. -`-EL' +'-EL' Link little-endian objects. This affects the default output format. -`-f NAME' -`--auxiliary=NAME' +'-f NAME' +'--auxiliary=NAME' When creating an ELF shared object, set the internal DT_AUXILIARY field to the specified name. This tells the dynamic linker that the symbol table of the shared object should be used as an @@ -363,13 +356,12 @@ GNU linker: entries will be created in the order in which they appear on the command line. -`-F NAME' -`--filter=NAME' +'-F NAME' +'--filter=NAME' When creating an ELF shared object, set the internal DT_FILTER field to the specified name. This tells the dynamic linker that - the symbol table of the shared object which is being created - should be used as a filter on the symbol table of the shared - object NAME. + the symbol table of the shared object which is being created should + be used as a filter on the symbol table of the shared object NAME. If you later link a program against this filter object, then, when you run the program, the dynamic linker will see the DT_FILTER @@ -379,128 +371,124 @@ GNU linker: filter object can be used to select a subset of the symbols provided by the object NAME. - Some older linkers used the `-F' option throughout a compilation + Some older linkers used the '-F' option throughout a compilation toolchain for specifying object-file format for both input and - output object files. The GNU linker uses other mechanisms for - this purpose: the `-b', `--format', `--oformat' options, the - `TARGET' command in linker scripts, and the `GNUTARGET' - environment variable. The GNU linker will ignore the `-F' option - when not creating an ELF shared object. + output object files. The GNU linker uses other mechanisms for this + purpose: the '-b', '--format', '--oformat' options, the 'TARGET' + command in linker scripts, and the 'GNUTARGET' environment + variable. The GNU linker will ignore the '-F' option when not + creating an ELF shared object. -`-fini=NAME' +'-fini=NAME' When creating an ELF executable or shared object, call NAME when the executable or shared object is unloaded, by setting DT_FINI to - the address of the function. By default, the linker uses `_fini' + the address of the function. By default, the linker uses '_fini' as the function to call. -`-g' +'-g' Ignored. Provided for compatibility with other tools. -`-G VALUE' -`--gpsize=VALUE' +'-G VALUE' +'--gpsize=VALUE' Set the maximum size of objects to be optimized using the GP register to SIZE. This is only meaningful for object file formats - such as MIPS ECOFF which supports putting large and small objects - into different sections. This is ignored for other object file - formats. + such as MIPS ELF that support putting large and small objects into + different sections. This is ignored for other object file formats. -`-h NAME' -`-soname=NAME' +'-h NAME' +'-soname=NAME' When creating an ELF shared object, set the internal DT_SONAME field to the specified name. When an executable is linked with a - shared object which has a DT_SONAME field, then when the - executable is run the dynamic linker will attempt to load the - shared object specified by the DT_SONAME field rather than the - using the file name given to the linker. + shared object which has a DT_SONAME field, then when the executable + is run the dynamic linker will attempt to load the shared object + specified by the DT_SONAME field rather than the using the file + name given to the linker. -`-i' - Perform an incremental link (same as option `-r'). +'-i' + Perform an incremental link (same as option '-r'). -`-init=NAME' +'-init=NAME' When creating an ELF executable or shared object, call NAME when the executable or shared object is loaded, by setting DT_INIT to - the address of the function. By default, the linker uses `_init' + the address of the function. By default, the linker uses '_init' as the function to call. -`-l NAMESPEC' -`--library=NAMESPEC' - Add the archive or object file specified by NAMESPEC to the list - of files to link. This option may be used any number of times. - If NAMESPEC is of the form `:FILENAME', `ld' will search the - library path for a file called FILENAME, otherwise it will search - the library path for a file called `libNAMESPEC.a'. - - On systems which support shared libraries, `ld' may also search for - files other than `libNAMESPEC.a'. Specifically, on ELF and SunOS - systems, `ld' will search a directory for a library called - `libNAMESPEC.so' before searching for one called `libNAMESPEC.a'. - (By convention, a `.so' extension indicates a shared library.) - Note that this behavior does not apply to `:FILENAME', which - always specifies a file called FILENAME. +'-l NAMESPEC' +'--library=NAMESPEC' + Add the archive or object file specified by NAMESPEC to the list of + files to link. This option may be used any number of times. If + NAMESPEC is of the form ':FILENAME', 'ld' will search the library + path for a file called FILENAME, otherwise it will search the + library path for a file called 'libNAMESPEC.a'. + + On systems which support shared libraries, 'ld' may also search for + files other than 'libNAMESPEC.a'. Specifically, on ELF and SunOS + systems, 'ld' will search a directory for a library called + 'libNAMESPEC.so' before searching for one called 'libNAMESPEC.a'. + (By convention, a '.so' extension indicates a shared library.) + Note that this behavior does not apply to ':FILENAME', which always + specifies a file called FILENAME. The linker will search an archive only once, at the location where it is specified on the command line. If the archive defines a - symbol which was undefined in some object which appeared before - the archive on the command line, the linker will include the - appropriate file(s) from the archive. However, an undefined - symbol in an object appearing later on the command line will not - cause the linker to search the archive again. + symbol which was undefined in some object which appeared before the + archive on the command line, the linker will include the + appropriate file(s) from the archive. However, an undefined symbol + in an object appearing later on the command line will not cause the + linker to search the archive again. - See the `-(' option for a way to force the linker to search + See the '-(' option for a way to force the linker to search archives multiple times. You may list the same archive multiple times on the command line. This type of archive searching is standard for Unix linkers. - However, if you are using `ld' on AIX, note that it is different + However, if you are using 'ld' on AIX, note that it is different from the behaviour of the AIX linker. -`-L SEARCHDIR' -`--library-path=SEARCHDIR' - Add path SEARCHDIR to the list of paths that `ld' will search for - archive libraries and `ld' control scripts. You may use this +'-L SEARCHDIR' +'--library-path=SEARCHDIR' + Add path SEARCHDIR to the list of paths that 'ld' will search for + archive libraries and 'ld' control scripts. You may use this option any number of times. The directories are searched in the - order in which they are specified on the command line. - Directories specified on the command line are searched before the - default directories. All `-L' options apply to all `-l' options, - regardless of the order in which the options appear. `-L' options - do not affect how `ld' searches for a linker script unless `-T' + order in which they are specified on the command line. Directories + specified on the command line are searched before the default + directories. All '-L' options apply to all '-l' options, + regardless of the order in which the options appear. '-L' options + do not affect how 'ld' searches for a linker script unless '-T' option is specified. - If SEARCHDIR begins with `=', then the `=' will be replaced by the + If SEARCHDIR begins with '=', then the '=' will be replaced by the "sysroot prefix", a path specified when the linker is configured. The default set of paths searched (without being specified with - `-L') depends on which emulation mode `ld' is using, and in some + '-L') depends on which emulation mode 'ld' is using, and in some cases also on how it was configured. *Note Environment::. The paths can also be specified in a link script with the - `SEARCH_DIR' command. Directories specified this way are searched + 'SEARCH_DIR' command. Directories specified this way are searched at the point in which the linker script appears in the command line. -`-m EMULATION' +'-m EMULATION' Emulate the EMULATION linker. You can list the available - emulations with the `--verbose' or `-V' options. + emulations with the '--verbose' or '-V' options. - If the `-m' option is not used, the emulation is taken from the - `LDEMULATION' environment variable, if that is defined. + If the '-m' option is not used, the emulation is taken from the + 'LDEMULATION' environment variable, if that is defined. Otherwise, the default emulation depends upon how the linker was configured. -`-M' -`--print-map' +'-M' +'--print-map' Print a link map to the standard output. A link map provides information about the link, including the following: * Where object files are mapped into memory. - * How common symbols are allocated. - * All archive members included in the link, with a mention of the symbol which caused the archive member to be brought in. - * The values assigned to symbols. Note - symbols whose values are computed by an expression @@ -508,184 +496,183 @@ GNU linker: symbol may not have correct result displayed in the link map. This is because the linker discards intermediate results and only retains the final value of an expression. Under such - circumstances the linker will display the final value - enclosed by square brackets. Thus for example a linker - script containing: + circumstances the linker will display the final value enclosed + by square brackets. Thus for example a linker script + containing: foo = 1 foo = foo * 4 foo = foo + 8 - will produce the following output in the link map if the `-M' + will produce the following output in the link map if the '-M' option is used: 0x00000001 foo = 0x1 [0x0000000c] foo = (foo * 0x4) [0x0000000c] foo = (foo + 0x8) - See *note Expressions:: for more information about - expressions in linker scripts. + See *note Expressions:: for more information about expressions + in linker scripts. -`-n' -`--nmagic' +'-n' +'--nmagic' Turn off page alignment of sections, and disable linking against shared libraries. If the output format supports Unix style magic - numbers, mark the output as `NMAGIC'. + numbers, mark the output as 'NMAGIC'. -`-N' -`--omagic' +'-N' +'--omagic' Set the text and data sections to be readable and writable. Also, do not page-align the data segment, and disable linking against shared libraries. If the output format supports Unix style magic - numbers, mark the output as `OMAGIC'. Note: Although a writable - text section is allowed for PE-COFF targets, it does not conform - to the format specification published by Microsoft. + numbers, mark the output as 'OMAGIC'. Note: Although a writable + text section is allowed for PE-COFF targets, it does not conform to + the format specification published by Microsoft. -`--no-omagic' - This option negates most of the effects of the `-N' option. It +'--no-omagic' + This option negates most of the effects of the '-N' option. It sets the text section to be read-only, and forces the data segment to be page-aligned. Note - this option does not enable linking - against shared libraries. Use `-Bdynamic' for this. + against shared libraries. Use '-Bdynamic' for this. -`-o OUTPUT' -`--output=OUTPUT' - Use OUTPUT as the name for the program produced by `ld'; if this - option is not specified, the name `a.out' is used by default. The - script command `OUTPUT' can also specify the output file name. +'-o OUTPUT' +'--output=OUTPUT' + Use OUTPUT as the name for the program produced by 'ld'; if this + option is not specified, the name 'a.out' is used by default. The + script command 'OUTPUT' can also specify the output file name. -`-O LEVEL' - If LEVEL is a numeric values greater than zero `ld' optimizes the +'-O LEVEL' + If LEVEL is a numeric values greater than zero 'ld' optimizes the output. This might take significantly longer and therefore probably should only be enabled for the final binary. At the moment this option only affects ELF shared library generation. Future releases of the linker may make more use of this option. - Also currently there is no difference in the linker's behaviour - for different non-zero values of this option. Again this may - change with future releases. + Also currently there is no difference in the linker's behaviour for + different non-zero values of this option. Again this may change + with future releases. -`-q' -`--emit-relocs' +'-q' +'--emit-relocs' Leave relocation sections and contents in fully linked executables. - Post link analysis and optimization tools may need this - information in order to perform correct modifications of - executables. This results in larger executables. + Post link analysis and optimization tools may need this information + in order to perform correct modifications of executables. This + results in larger executables. This option is currently only supported on ELF platforms. -`--force-dynamic' +'--force-dynamic' Force the output file to have dynamic sections. This option is specific to VxWorks targets. -`-r' -`--relocatable' - Generate relocatable output--i.e., generate an output file that - can in turn serve as input to `ld'. This is often called "partial +'-r' +'--relocatable' + Generate relocatable output--i.e., generate an output file that can + in turn serve as input to 'ld'. This is often called "partial linking". As a side effect, in environments that support standard Unix magic numbers, this option also sets the output file's magic - number to `OMAGIC'. If this option is not specified, an absolute + number to 'OMAGIC'. If this option is not specified, an absolute file is produced. When linking C++ programs, this option _will - not_ resolve references to constructors; to do that, use `-Ur'. + not_ resolve references to constructors; to do that, use '-Ur'. When an input file does not have the same format as the output - file, partial linking is only supported if that input file does - not contain any relocations. Different output formats can have - further restrictions; for example some `a.out'-based formats do - not support partial linking with input files in other formats at - all. + file, partial linking is only supported if that input file does not + contain any relocations. Different output formats can have further + restrictions; for example some 'a.out'-based formats do not support + partial linking with input files in other formats at all. - This option does the same thing as `-i'. + This option does the same thing as '-i'. -`-R FILENAME' -`--just-symbols=FILENAME' +'-R FILENAME' +'--just-symbols=FILENAME' Read symbol names and their addresses from FILENAME, but do not relocate it or include it in the output. This allows your output file to refer symbolically to absolute locations of memory defined in other programs. You may use this option more than once. - For compatibility with other ELF linkers, if the `-R' option is + For compatibility with other ELF linkers, if the '-R' option is followed by a directory name, rather than a file name, it is - treated as the `-rpath' option. + treated as the '-rpath' option. -`-s' -`--strip-all' +'-s' +'--strip-all' Omit all symbol information from the output file. -`-S' -`--strip-debug' +'-S' +'--strip-debug' Omit debugger symbol information (but not all symbols) from the output file. -`-t' -`--trace' - Print the names of the input files as `ld' processes them. +'-t' +'--trace' + Print the names of the input files as 'ld' processes them. -`-T SCRIPTFILE' -`--script=SCRIPTFILE' - Use SCRIPTFILE as the linker script. This script replaces `ld''s +'-T SCRIPTFILE' +'--script=SCRIPTFILE' + Use SCRIPTFILE as the linker script. This script replaces 'ld''s default linker script (rather than adding to it), so COMMANDFILE must specify everything necessary to describe the output file. *Note Scripts::. If SCRIPTFILE does not exist in the current - directory, `ld' looks for it in the directories specified by any - preceding `-L' options. Multiple `-T' options accumulate. + directory, 'ld' looks for it in the directories specified by any + preceding '-L' options. Multiple '-T' options accumulate. -`-dT SCRIPTFILE' -`--default-script=SCRIPTFILE' +'-dT SCRIPTFILE' +'--default-script=SCRIPTFILE' Use SCRIPTFILE as the default linker script. *Note Scripts::. - This option is similar to the `--script' option except that + This option is similar to the '--script' option except that processing of the script is delayed until after the rest of the command line has been processed. This allows options placed after - the `--default-script' option on the command line to affect the + the '--default-script' option on the command line to affect the behaviour of the linker script, which can be important when the - linker command line cannot be directly controlled by the user. - (eg because the command line is being constructed by another tool, - such as `gcc'). + linker command line cannot be directly controlled by the user. (eg + because the command line is being constructed by another tool, such + as 'gcc'). -`-u SYMBOL' -`--undefined=SYMBOL' +'-u SYMBOL' +'--undefined=SYMBOL' Force SYMBOL to be entered in the output file as an undefined symbol. Doing this may, for example, trigger linking of additional - modules from standard libraries. `-u' may be repeated with + modules from standard libraries. '-u' may be repeated with different option arguments to enter additional undefined symbols. - This option is equivalent to the `EXTERN' linker script command. + This option is equivalent to the 'EXTERN' linker script command. -`-Ur' +'-Ur' For anything other than C++ programs, this option is equivalent to - `-r': it generates relocatable output--i.e., an output file that - can in turn serve as input to `ld'. When linking C++ programs, - `-Ur' _does_ resolve references to constructors, unlike `-r'. It - does not work to use `-Ur' on files that were themselves linked - with `-Ur'; once the constructor table has been built, it cannot - be added to. Use `-Ur' only for the last partial link, and `-r' - for the others. - -`--unique[=SECTION]' + '-r': it generates relocatable output--i.e., an output file that + can in turn serve as input to 'ld'. When linking C++ programs, + '-Ur' _does_ resolve references to constructors, unlike '-r'. It + does not work to use '-Ur' on files that were themselves linked + with '-Ur'; once the constructor table has been built, it cannot be + added to. Use '-Ur' only for the last partial link, and '-r' for + the others. + +'--unique[=SECTION]' Creates a separate output section for every input section matching SECTION, or if the optional wildcard SECTION argument is missing, for every orphan input section. An orphan section is one not specifically mentioned in a linker script. You may use this option - multiple times on the command line; It prevents the normal - merging of input sections with the same name, overriding output - section assignments in a linker script. - -`-v' -`--version' -`-V' - Display the version number for `ld'. The `-V' option also lists + multiple times on the command line; It prevents the normal merging + of input sections with the same name, overriding output section + assignments in a linker script. + +'-v' +'--version' +'-V' + Display the version number for 'ld'. The '-V' option also lists the supported emulations. -`-x' -`--discard-all' +'-x' +'--discard-all' Delete all local symbols. -`-X' -`--discard-locals' +'-X' +'--discard-locals' Delete all temporary local symbols. (These symbols start with - system-specific local label prefixes, typically `.L' for ELF - systems or `L' for traditional a.out systems.) + system-specific local label prefixes, typically '.L' for ELF + systems or 'L' for traditional a.out systems.) -`-y SYMBOL' -`--trace-symbol=SYMBOL' +'-y SYMBOL' +'--trace-symbol=SYMBOL' Print the name of each linked file in which SYMBOL appears. This option may be given any number of times. On many systems it is necessary to prepend an underscore. @@ -693,29 +680,30 @@ GNU linker: This option is useful when you have an undefined symbol in your link but don't know where the reference is coming from. -`-Y PATH' +'-Y PATH' Add PATH to the default library search path. This option exists for Solaris compatibility. -`-z KEYWORD' +'-z KEYWORD' The recognized keywords are: - `combreloc' + + 'combreloc' Combines multiple reloc sections and sorts them to make dynamic symbol lookup caching possible. - `defs' + 'defs' Disallows undefined symbols in object files. Undefined symbols in shared libraries are still allowed. - `execstack' + 'execstack' Marks the object as requiring executable stack. - `global' + 'global' This option is only meaningful when building a shared object. It makes the symbols defined by this shared object available for symbol resolution of subsequently loaded libraries. - `initfirst' + 'initfirst' This option is only meaningful when building a shared object. It marks the object so that its runtime initialization will occur before the runtime initialization of any other objects @@ -723,181 +711,175 @@ GNU linker: runtime finalization of the object will occur after the runtime finalization of any other objects. - `interpose' + 'interpose' Marks the object that its symbol table interposes before all symbols but the primary executable. - `lazy' + 'lazy' When generating an executable or shared library, mark it to tell the dynamic linker to defer function call resolution to the point when the function is called (lazy binding), rather than at load time. Lazy binding is the default. - `loadfltr' - Marks the object that its filters be processed immediately at + 'loadfltr' + Marks the object that its filters be processed immediately at runtime. - `muldefs' + 'muldefs' Allows multiple definitions. - `nocombreloc' + 'nocombreloc' Disables multiple reloc sections combining. - `nocopyreloc' + 'nocopyreloc' Disables production of copy relocs. - `nodefaultlib' + 'nodefaultlib' Marks the object that the search for dependencies of this object will ignore any default library search paths. - `nodelete' + 'nodelete' Marks the object shouldn't be unloaded at runtime. - `nodlopen' - Marks the object not available to `dlopen'. + 'nodlopen' + Marks the object not available to 'dlopen'. - `nodump' - Marks the object can not be dumped by `dldump'. + 'nodump' + Marks the object can not be dumped by 'dldump'. - `noexecstack' + 'noexecstack' Marks the object as not requiring executable stack. - `norelro' - Don't create an ELF `PT_GNU_RELRO' segment header in the + 'norelro' + Don't create an ELF 'PT_GNU_RELRO' segment header in the object. - `now' + 'now' When generating an executable or shared library, mark it to tell the dynamic linker to resolve all symbols when the program is started, or when the shared library is linked to - using dlopen, instead of deferring function call resolution - to the point when the function is first called. + using dlopen, instead of deferring function call resolution to + the point when the function is first called. - `origin' + 'origin' Marks the object may contain $ORIGIN. - `relro' - Create an ELF `PT_GNU_RELRO' segment header in the object. - - `nosecondary' - Convert secondary symbols to weak symbols when generating a - shared library. + 'relro' + Create an ELF 'PT_GNU_RELRO' segment header in the object. - `max-page-size=VALUE' + 'max-page-size=VALUE' Set the emulation maximum page size to VALUE. - `common-page-size=VALUE' + 'common-page-size=VALUE' Set the emulation common page size to VALUE. - `stack-size=VALUE' - Specify a stack size for in an ELF `PT_GNU_STACK' segment. + 'stack-size=VALUE' + Specify a stack size for in an ELF 'PT_GNU_STACK' segment. Specifying zero will override any default non-zero sized - `PT_GNU_STACK' segment creation. - + 'PT_GNU_STACK' segment creation. Other keywords are ignored for Solaris compatibility. -`-( ARCHIVES -)' -`--start-group ARCHIVES --end-group' - The ARCHIVES should be a list of archive files. They may be - either explicit file names, or `-l' options. +'-( ARCHIVES -)' +'--start-group ARCHIVES --end-group' + The ARCHIVES should be a list of archive files. They may be either + explicit file names, or '-l' options. The specified archives are searched repeatedly until no new - undefined references are created. Normally, an archive is - searched only once in the order that it is specified on the - command line. If a symbol in that archive is needed to resolve an - undefined symbol referred to by an object in an archive that - appears later on the command line, the linker would not be able to - resolve that reference. By grouping the archives, they all be - searched repeatedly until all possible references are resolved. + undefined references are created. Normally, an archive is searched + only once in the order that it is specified on the command line. + If a symbol in that archive is needed to resolve an undefined + symbol referred to by an object in an archive that appears later on + the command line, the linker would not be able to resolve that + reference. By grouping the archives, they all be searched + repeatedly until all possible references are resolved. Using this option has a significant performance cost. It is best to use it only when there are unavoidable circular references between two or more archives. -`--accept-unknown-input-arch' -`--no-accept-unknown-input-arch' +'--accept-unknown-input-arch' +'--no-accept-unknown-input-arch' Tells the linker to accept input files whose architecture cannot be recognised. The assumption is that the user knows what they are doing and deliberately wants to link in these unknown input files. This was the default behaviour of the linker, before release 2.14. The default behaviour from release 2.14 onwards is to reject such - input files, and so the `--accept-unknown-input-arch' option has + input files, and so the '--accept-unknown-input-arch' option has been added to restore the old behaviour. -`--as-needed' -`--no-as-needed' +'--as-needed' +'--no-as-needed' This option affects ELF DT_NEEDED tags for dynamic libraries - mentioned on the command line after the `--as-needed' option. + mentioned on the command line after the '--as-needed' option. Normally the linker will add a DT_NEEDED tag for each dynamic library mentioned on the command line, regardless of whether the - library is actually needed or not. `--as-needed' causes a + library is actually needed or not. '--as-needed' causes a DT_NEEDED tag to only be emitted for a library that _at that point - in the link_ satisfies a non-weak undefined symbol reference from - a regular object file or, if the library is not found in the + in the link_ satisfies a non-weak undefined symbol reference from a + regular object file or, if the library is not found in the DT_NEEDED lists of other libraries, a non-weak undefined symbol reference from another dynamic library. Object files or libraries appearing on the command line _after_ the library in question do not affect whether the library is seen as needed. This is similar to the rules for extraction of object files from archives. - `--no-as-needed' restores the default behaviour. + '--no-as-needed' restores the default behaviour. -`--add-needed' -`--no-add-needed' +'--add-needed' +'--no-add-needed' These two options have been deprecated because of the similarity of - their names to the `--as-needed' and `--no-as-needed' options. - They have been replaced by `--copy-dt-needed-entries' and - `--no-copy-dt-needed-entries'. + their names to the '--as-needed' and '--no-as-needed' options. + They have been replaced by '--copy-dt-needed-entries' and + '--no-copy-dt-needed-entries'. -`-assert KEYWORD' +'-assert KEYWORD' This option is ignored for SunOS compatibility. -`-Bdynamic' -`-dy' -`-call_shared' +'-Bdynamic' +'-dy' +'-call_shared' Link against dynamic libraries. This is only meaningful on - platforms for which shared libraries are supported. This option - is normally the default on such platforms. The different variants - of this option are for compatibility with various systems. You - may use this option multiple times on the command line: it affects - library searching for `-l' options which follow it. - -`-Bgroup' - Set the `DF_1_GROUP' flag in the `DT_FLAGS_1' entry in the dynamic + platforms for which shared libraries are supported. This option is + normally the default on such platforms. The different variants of + this option are for compatibility with various systems. You may + use this option multiple times on the command line: it affects + library searching for '-l' options which follow it. + +'-Bgroup' + Set the 'DF_1_GROUP' flag in the 'DT_FLAGS_1' entry in the dynamic section. This causes the runtime linker to handle lookups in this object and its dependencies to be performed only inside the group. - `--unresolved-symbols=report-all' is implied. This option is only + '--unresolved-symbols=report-all' is implied. This option is only meaningful on ELF platforms which support shared libraries. -`-Bstatic' -`-dn' -`-non_shared' -`-static' +'-Bstatic' +'-dn' +'-non_shared' +'-static' Do not link against shared libraries. This is only meaningful on platforms for which shared libraries are supported. The different - variants of this option are for compatibility with various - systems. You may use this option multiple times on the command - line: it affects library searching for `-l' options which follow - it. This option also implies `--unresolved-symbols=report-all'. - This option can be used with `-shared'. Doing so means that a - shared library is being created but that all of the library's - external references must be resolved by pulling in entries from - static libraries. - -`-Bsymbolic' + variants of this option are for compatibility with various systems. + You may use this option multiple times on the command line: it + affects library searching for '-l' options which follow it. This + option also implies '--unresolved-symbols=report-all'. This option + can be used with '-shared'. Doing so means that a shared library + is being created but that all of the library's external references + must be resolved by pulling in entries from static libraries. + +'-Bsymbolic' When creating a shared library, bind references to global symbols to the definition within the shared library, if any. Normally, it is possible for a program linked against a shared library to override the definition within the shared library. This option is only meaningful on ELF platforms which support shared libraries. -`-Bsymbolic-functions' +'-Bsymbolic-functions' When creating a shared library, bind references to global function symbols to the definition within the shared library, if any. This option is only meaningful on ELF platforms which support shared libraries. -`--dynamic-list=DYNAMIC-LIST-FILE' +'--dynamic-list=DYNAMIC-LIST-FILE' Specify the name of a dynamic list file to the linker. This is typically used when creating shared libraries to specify a list of global symbols whose references shouldn't be bound to the @@ -910,42 +892,42 @@ GNU linker: without scope and node name. See *note VERSION:: for more information. -`--dynamic-list-data' +'--dynamic-list-data' Include all global data symbols to the dynamic list. -`--dynamic-list-cpp-new' +'--dynamic-list-cpp-new' Provide the builtin dynamic list for C++ operator new and delete. It is mainly useful for building shared libstdc++. -`--dynamic-list-cpp-typeinfo' +'--dynamic-list-cpp-typeinfo' Provide the builtin dynamic list for C++ runtime type identification. -`--check-sections' -`--no-check-sections' +'--check-sections' +'--no-check-sections' Asks the linker _not_ to check section addresses after they have been assigned to see if there are any overlaps. Normally the linker will perform this check, and if it finds any overlaps it will produce suitable error messages. The linker does know about, and does make allowances for sections in overlays. The default behaviour can be restored by using the command line switch - `--check-sections'. Section overlap is not usually checked for + '--check-sections'. Section overlap is not usually checked for relocatable links. You can force checking in that case by using - the `--check-sections' option. + the '--check-sections' option. -`--copy-dt-needed-entries' -`--no-copy-dt-needed-entries' +'--copy-dt-needed-entries' +'--no-copy-dt-needed-entries' This option affects the treatment of dynamic libraries referred to by DT_NEEDED tags _inside_ ELF dynamic libraries mentioned on the command line. Normally the linker won't add a DT_NEEDED tag to the output binary for each library mentioned in a DT_NEEDED tag in an - input dynamic library. With `--copy-dt-needed-entries' specified + input dynamic library. With '--copy-dt-needed-entries' specified on the command line however any dynamic libraries that follow it - will have their DT_NEEDED entries added. The default behaviour - can be restored with `--no-copy-dt-needed-entries'. + will have their DT_NEEDED entries added. The default behaviour can + be restored with '--no-copy-dt-needed-entries'. This option also has an effect on the resolution of symbols in - dynamic libraries. With `--copy-dt-needed-entries' dynamic + dynamic libraries. With '--copy-dt-needed-entries' dynamic libraries mentioned on the command line will be recursively searched, following their DT_NEEDED tags to other libraries, in order to resolve symbols required by the output binary. With the @@ -953,90 +935,91 @@ GNU linker: follow it will stop with the dynamic library itself. No DT_NEEDED links will be traversed to resolve symbols. -`--cref' +'--cref' Output a cross reference table. If a linker map file is being generated, the cross reference table is printed to the map file. Otherwise, it is printed on the standard output. The format of the table is intentionally simple, so that it may be - easily processed by a script if necessary. The symbols are - printed out, sorted by name. For each symbol, a list of file - names is given. If the symbol is defined, the first file listed - is the location of the definition. The remaining files contain - references to the symbol. - -`--no-define-common' + easily processed by a script if necessary. The symbols are printed + out, sorted by name. For each symbol, a list of file names is + given. If the symbol is defined, the first file listed is the + location of the definition. If the symbol is defined as a common + value then any files where this happens appear next. Finally any + files that reference the symbol are listed. + +'--no-define-common' This option inhibits the assignment of addresses to common symbols. - The script command `INHIBIT_COMMON_ALLOCATION' has the same effect. + The script command 'INHIBIT_COMMON_ALLOCATION' has the same effect. *Note Miscellaneous Commands::. - The `--no-define-common' option allows decoupling the decision to + The '--no-define-common' option allows decoupling the decision to assign addresses to Common symbols from the choice of the output - file type; otherwise a non-Relocatable output type forces - assigning addresses to Common symbols. Using `--no-define-common' - allows Common symbols that are referenced from a shared library to - be assigned addresses only in the main program. This eliminates - the unused duplicate space in the shared library, and also - prevents any possible confusion over resolving to the wrong - duplicate when there are many dynamic modules with specialized - search paths for runtime symbol resolution. - -`--defsym=SYMBOL=EXPRESSION' + file type; otherwise a non-Relocatable output type forces assigning + addresses to Common symbols. Using '--no-define-common' allows + Common symbols that are referenced from a shared library to be + assigned addresses only in the main program. This eliminates the + unused duplicate space in the shared library, and also prevents any + possible confusion over resolving to the wrong duplicate when there + are many dynamic modules with specialized search paths for runtime + symbol resolution. + +'--defsym=SYMBOL=EXPRESSION' Create a global symbol in the output file, containing the absolute - address given by EXPRESSION. You may use this option as many - times as necessary to define multiple symbols in the command line. - A limited form of arithmetic is supported for the EXPRESSION in - this context: you may give a hexadecimal constant or the name of - an existing symbol, or use `+' and `-' to add or subtract - hexadecimal constants or symbols. If you need more elaborate - expressions, consider using the linker command language from a - script (*note Assignment: Symbol Definitions: Assignments.). - _Note:_ there should be no white space between SYMBOL, the equals - sign ("<=>"), and EXPRESSION. - -`--demangle[=STYLE]' -`--no-demangle' + address given by EXPRESSION. You may use this option as many times + as necessary to define multiple symbols in the command line. A + limited form of arithmetic is supported for the EXPRESSION in this + context: you may give a hexadecimal constant or the name of an + existing symbol, or use '+' and '-' to add or subtract hexadecimal + constants or symbols. If you need more elaborate expressions, + consider using the linker command language from a script (*note + Assignment: Symbol Definitions: Assignments.). _Note:_ there + should be no white space between SYMBOL, the equals sign ("<=>"), + and EXPRESSION. + +'--demangle[=STYLE]' +'--no-demangle' These options control whether to demangle symbol names in error - messages and other output. When the linker is told to demangle, - it tries to present symbol names in a readable fashion: it strips - leading underscores if they are used by the object file format, - and converts C++ mangled symbol names into user readable names. + messages and other output. When the linker is told to demangle, it + tries to present symbol names in a readable fashion: it strips + leading underscores if they are used by the object file format, and + converts C++ mangled symbol names into user readable names. Different compilers have different mangling styles. The optional demangling style argument can be used to choose an appropriate demangling style for your compiler. The linker will demangle by - default unless the environment variable `COLLECT_NO_DEMANGLE' is + default unless the environment variable 'COLLECT_NO_DEMANGLE' is set. These options may be used to override the default. -`-IFILE' -`--dynamic-linker=FILE' +'-IFILE' +'--dynamic-linker=FILE' Set the name of the dynamic linker. This is only meaningful when generating dynamically linked ELF executables. The default dynamic - linker is normally correct; don't use this unless you know what - you are doing. + linker is normally correct; don't use this unless you know what you + are doing. -`--fatal-warnings' -`--no-fatal-warnings' +'--fatal-warnings' +'--no-fatal-warnings' Treat all warnings as errors. The default behaviour can be - restored with the option `--no-fatal-warnings'. + restored with the option '--no-fatal-warnings'. -`--force-exe-suffix' +'--force-exe-suffix' Make sure that an output file has a .exe suffix. If a successfully built fully linked output file does not have a - `.exe' or `.dll' suffix, this option forces the linker to copy the - output file to one of the same name with a `.exe' suffix. This + '.exe' or '.dll' suffix, this option forces the linker to copy the + output file to one of the same name with a '.exe' suffix. This option is useful when using unmodified Unix makefiles on a - Microsoft Windows host, since some versions of Windows won't run - an image unless it ends in a `.exe' suffix. + Microsoft Windows host, since some versions of Windows won't run an + image unless it ends in a '.exe' suffix. -`--gc-sections' -`--no-gc-sections' +'--gc-sections' +'--no-gc-sections' Enable garbage collection of unused input sections. It is ignored on targets that do not support this option. The default behaviour (of not performing this garbage collection) can be restored by - specifying `--no-gc-sections' on the command line. + specifying '--no-gc-sections' on the command line. - `--gc-sections' decides which input sections are used by examining + '--gc-sections' decides which input sections are used by examining symbols and relocations. The section containing the entry symbol and all sections containing symbols undefined on the command-line will be kept, as will sections containing symbols referenced by @@ -1044,81 +1027,80 @@ GNU linker: linker must assume that any visible symbol is referenced. Once this initial set of sections has been determined, the linker recursively marks as used any section referenced by their - relocations. See `--entry' and `--undefined'. + relocations. See '--entry' and '--undefined'. This option can be set when doing a partial link (enabled with - option `-r'). In this case the root of symbols kept must be - explicitly specified either by an `--entry' or `--undefined' - option or by a `ENTRY' command in the linker script. + option '-r'). In this case the root of symbols kept must be + explicitly specified either by an '--entry' or '--undefined' option + or by a 'ENTRY' command in the linker script. -`--print-gc-sections' -`--no-print-gc-sections' +'--print-gc-sections' +'--no-print-gc-sections' List all sections removed by garbage collection. The listing is printed on stderr. This option is only effective if garbage - collection has been enabled via the `--gc-sections') option. The + collection has been enabled via the '--gc-sections') option. The default behaviour (of not listing the sections that are removed) - can be restored by specifying `--no-print-gc-sections' on the + can be restored by specifying '--no-print-gc-sections' on the command line. -`--print-output-format' +'--print-output-format' Print the name of the default output format (perhaps influenced by other command-line options). This is the string that would appear - in an `OUTPUT_FORMAT' linker script command (*note File + in an 'OUTPUT_FORMAT' linker script command (*note File Commands::). -`--help' +'--help' Print a summary of the command-line options on the standard output and exit. -`--target-help' +'--target-help' Print a summary of all target specific options on the standard output and exit. -`-Map=MAPFILE' +'-Map=MAPFILE' Print a link map to the file MAPFILE. See the description of the - `-M' option, above. + '-M' option, above. -`--no-keep-memory' - `ld' normally optimizes for speed over memory usage by caching the - symbol tables of input files in memory. This option tells `ld' to +'--no-keep-memory' + 'ld' normally optimizes for speed over memory usage by caching the + symbol tables of input files in memory. This option tells 'ld' to instead optimize for memory usage, by rereading the symbol tables - as necessary. This may be required if `ld' runs out of memory + as necessary. This may be required if 'ld' runs out of memory space while linking a large executable. -`--no-undefined' -`-z defs' +'--no-undefined' +'-z defs' Report unresolved symbol references from regular object files. This is done even if the linker is creating a non-symbolic shared - library. The switch `--[no-]allow-shlib-undefined' controls the + library. The switch '--[no-]allow-shlib-undefined' controls the behaviour for reporting unresolved references found in shared libraries being linked in. -`--allow-multiple-definition' -`-z muldefs' +'--allow-multiple-definition' +'-z muldefs' Normally when a symbol is defined multiple times, the linker will - report a fatal error. These options allow multiple definitions and + report a fatal error. These options allow multiple definitions and the first definition will be used. -`--allow-shlib-undefined' -`--no-allow-shlib-undefined' +'--allow-shlib-undefined' +'--no-allow-shlib-undefined' Allows or disallows undefined symbols in shared libraries. This - switch is similar to `--no-undefined' except that it determines - the behaviour when the undefined symbols are in a shared library - rather than a regular object file. It does not affect how - undefined symbols in regular object files are handled. + switch is similar to '--no-undefined' except that it determines the + behaviour when the undefined symbols are in a shared library rather + than a regular object file. It does not affect how undefined + symbols in regular object files are handled. The default behaviour is to report errors for any undefined symbols referenced in shared libraries if the linker is being used to - create an executable, but to allow them if the linker is being - used to create a shared library. + create an executable, but to allow them if the linker is being used + to create a shared library. The reasons for allowing undefined symbol references in shared libraries specified at link time are that: - * A shared library specified at link time may not be the same - as the one that is available at load time, so the symbol - might actually be resolvable at load time. - + * A shared library specified at link time may not be the same as + the one that is available at load time, so the symbol might + actually be resolvable at load time. * There are some operating systems, eg BeOS and HPPA, where undefined symbols in shared libraries are normal. @@ -1127,63 +1109,62 @@ GNU linker: current architecture. This is used, for example, to dynamically select an appropriate memset function. -`--no-undefined-version' +'--no-undefined-version' Normally when a symbol has an undefined version, the linker will - ignore it. This option disallows symbols with undefined version + ignore it. This option disallows symbols with undefined version and a fatal error will be issued instead. -`--default-symver' +'--default-symver' Create and use a default symbol version (the soname) for unversioned exported symbols. -`--default-imported-symver' +'--default-imported-symver' Create and use a default symbol version (the soname) for unversioned imported symbols. -`--no-warn-mismatch' - Normally `ld' will give an error if you try to link together input +'--no-warn-mismatch' + Normally 'ld' will give an error if you try to link together input files that are mismatched for some reason, perhaps because they have been compiled for different processors or for different - endiannesses. This option tells `ld' that it should silently + endiannesses. This option tells 'ld' that it should silently permit such possible errors. This option should only be used with - care, in cases when you have taken some special action that - ensures that the linker errors are inappropriate. + care, in cases when you have taken some special action that ensures + that the linker errors are inappropriate. -`--no-warn-search-mismatch' - Normally `ld' will give a warning if it finds an incompatible +'--no-warn-search-mismatch' + Normally 'ld' will give a warning if it finds an incompatible library during a library search. This option silences the warning. -`--no-whole-archive' - Turn off the effect of the `--whole-archive' option for subsequent +'--no-whole-archive' + Turn off the effect of the '--whole-archive' option for subsequent archive files. -`--noinhibit-exec' +'--noinhibit-exec' Retain the executable output file whenever it is still usable. Normally, the linker will not produce an output file if it - encounters errors during the link process; it exits without - writing an output file when it issues any error whatsoever. - -`-nostdlib' - Only search library directories explicitly specified on the - command line. Library directories specified in linker scripts - (including linker scripts specified on the command line) are - ignored. - -`--oformat=OUTPUT-FORMAT' - `ld' may be configured to support more than one kind of object - file. If your `ld' is configured this way, you can use the - `--oformat' option to specify the binary format for the output - object file. Even when `ld' is configured to support alternative - object formats, you don't usually need to specify this, as `ld' + encounters errors during the link process; it exits without writing + an output file when it issues any error whatsoever. + +'-nostdlib' + Only search library directories explicitly specified on the command + line. Library directories specified in linker scripts (including + linker scripts specified on the command line) are ignored. + +'--oformat=OUTPUT-FORMAT' + 'ld' may be configured to support more than one kind of object + file. If your 'ld' is configured this way, you can use the + '--oformat' option to specify the binary format for the output + object file. Even when 'ld' is configured to support alternative + object formats, you don't usually need to specify this, as 'ld' should be configured to produce as a default output format the most usual format on each machine. OUTPUT-FORMAT is a text string, the name of a particular format supported by the BFD libraries. (You - can list the available binary formats with `objdump -i'.) The - script command `OUTPUT_FORMAT' can also specify the output format, + can list the available binary formats with 'objdump -i'.) The + script command 'OUTPUT_FORMAT' can also specify the output format, but this option overrides it. *Note BFD::. -`-pie' -`--pic-executable' +'-pie' +'--pic-executable' Create a position independent executable. This is currently only supported on ELF platforms. Position independent executables are similar to shared libraries in that they are relocated by the @@ -1192,166 +1173,159 @@ GNU linker: linked executables they can be executed and symbols defined in the executable cannot be overridden by shared libraries. -`-qmagic' +'-qmagic' This option is ignored for Linux compatibility. -`-Qy' +'-Qy' This option is ignored for SVR4 compatibility. -`--relax' -`--no-relax' +'--relax' +'--no-relax' An option with machine dependent effects. This option is only - supported on a few targets. *Note `ld' and the H8/300: H8/300. - *Note `ld' and the Intel 960 family: i960. *Note `ld' and Xtensa - Processors: Xtensa. *Note `ld' and the 68HC11 and 68HC12: - M68HC11/68HC12. *Note `ld' and PowerPC 32-bit ELF Support: - PowerPC ELF32. + supported on a few targets. *Note 'ld' and the H8/300: H8/300. + *Note 'ld' and the Intel 960 family: i960. *Note 'ld' and Xtensa + Processors: Xtensa. *Note 'ld' and the 68HC11 and 68HC12: + M68HC11/68HC12. *Note 'ld' and PowerPC 32-bit ELF Support: PowerPC + ELF32. - On some platforms the `--relax' option performs target specific, + On some platforms the '--relax' option performs target specific, global optimizations that become possible when the linker resolves addressing in the program, such as relaxing address modes, synthesizing new instructions, selecting shorter version of current instructions, and combining constant values. On some platforms these link time global optimizations may make - symbolic debugging of the resulting executable impossible. This - is known to be the case for the Matsushita MN10200 and MN10300 - family of processors. + symbolic debugging of the resulting executable impossible. This is + known to be the case for the Matsushita MN10200 and MN10300 family + of processors. - On platforms where this is not supported, `--relax' is accepted, + On platforms where this is not supported, '--relax' is accepted, but ignored. - On platforms where `--relax' is accepted the option `--no-relax' + On platforms where '--relax' is accepted the option '--no-relax' can be used to disable the feature. -`--retain-symbols-file=FILENAME' +'--retain-symbols-file=FILENAME' Retain _only_ the symbols listed in the file FILENAME, discarding all others. FILENAME is simply a flat file, with one symbol name per line. This option is especially useful in environments (such as VxWorks) where a large global symbol table is accumulated gradually, to conserve run-time memory. - `--retain-symbols-file' does _not_ discard undefined symbols, or + '--retain-symbols-file' does _not_ discard undefined symbols, or symbols needed for relocations. - You may only specify `--retain-symbols-file' once in the command - line. It overrides `-s' and `-S'. + You may only specify '--retain-symbols-file' once in the command + line. It overrides '-s' and '-S'. -`-rpath=DIR' +'-rpath=DIR' Add a directory to the runtime library search path. This is used - when linking an ELF executable with shared objects. All `-rpath' + when linking an ELF executable with shared objects. All '-rpath' arguments are concatenated and passed to the runtime linker, which - uses them to locate shared objects at runtime. The `-rpath' - option is also used when locating shared objects which are needed - by shared objects explicitly included in the link; see the - description of the `-rpath-link' option. If `-rpath' is not used - when linking an ELF executable, the contents of the environment - variable `LD_RUN_PATH' will be used if it is defined. - - The `-rpath' option may also be used on SunOS. By default, on + uses them to locate shared objects at runtime. The '-rpath' option + is also used when locating shared objects which are needed by + shared objects explicitly included in the link; see the description + of the '-rpath-link' option. If '-rpath' is not used when linking + an ELF executable, the contents of the environment variable + 'LD_RUN_PATH' will be used if it is defined. + + The '-rpath' option may also be used on SunOS. By default, on SunOS, the linker will form a runtime search patch out of all the - `-L' options it is given. If a `-rpath' option is used, the - runtime search path will be formed exclusively using the `-rpath' - options, ignoring the `-L' options. This can be useful when using - gcc, which adds many `-L' options which may be on NFS mounted file + '-L' options it is given. If a '-rpath' option is used, the + runtime search path will be formed exclusively using the '-rpath' + options, ignoring the '-L' options. This can be useful when using + gcc, which adds many '-L' options which may be on NFS mounted file systems. - For compatibility with other ELF linkers, if the `-R' option is + For compatibility with other ELF linkers, if the '-R' option is followed by a directory name, rather than a file name, it is - treated as the `-rpath' option. + treated as the '-rpath' option. -`-rpath-link=DIR' +'-rpath-link=DIR' When using ELF or SunOS, one shared library may require another. - This happens when an `ld -shared' link includes a shared library - as one of the input files. + This happens when an 'ld -shared' link includes a shared library as + one of the input files. When the linker encounters such a dependency when doing a non-shared, non-relocatable link, it will automatically try to locate the required shared library and include it in the link, if - it is not included explicitly. In such a case, the `-rpath-link' + it is not included explicitly. In such a case, the '-rpath-link' option specifies the first set of directories to search. The - `-rpath-link' option may specify a sequence of directory names + '-rpath-link' option may specify a sequence of directory names either by specifying a list of names separated by colons, or by appearing multiple times. This option should be used with caution as it overrides the search - path that may have been hard compiled into a shared library. In + path that may have been hard compiled into a shared library. In such a case it is possible to use unintentionally a different search path than the runtime linker would do. The linker uses the following search paths to locate required shared libraries: - 1. Any directories specified by `-rpath-link' options. - - 2. Any directories specified by `-rpath' options. The difference - between `-rpath' and `-rpath-link' is that directories - specified by `-rpath' options are included in the executable - and used at runtime, whereas the `-rpath-link' option is only - effective at link time. Searching `-rpath' in this way is + 1. Any directories specified by '-rpath-link' options. + 2. Any directories specified by '-rpath' options. The difference + between '-rpath' and '-rpath-link' is that directories + specified by '-rpath' options are included in the executable + and used at runtime, whereas the '-rpath-link' option is only + effective at link time. Searching '-rpath' in this way is only supported by native linkers and cross linkers which have - been configured with the `--with-sysroot' option. - - 3. On an ELF system, for native linkers, if the `-rpath' and - `-rpath-link' options were not used, search the contents of - the environment variable `LD_RUN_PATH'. - - 4. On SunOS, if the `-rpath' option was not used, search any - directories specified using `-L' options. - + been configured with the '--with-sysroot' option. + 3. On an ELF system, for native linkers, if the '-rpath' and + '-rpath-link' options were not used, search the contents of + the environment variable 'LD_RUN_PATH'. + 4. On SunOS, if the '-rpath' option was not used, search any + directories specified using '-L' options. 5. For a native linker, search the contents of the environment - variable `LD_LIBRARY_PATH'. - - 6. For a native ELF linker, the directories in `DT_RUNPATH' or - `DT_RPATH' of a shared library are searched for shared - libraries needed by it. The `DT_RPATH' entries are ignored if - `DT_RUNPATH' entries exist. - - 7. The default directories, normally `/lib' and `/usr/lib'. - + variable 'LD_LIBRARY_PATH'. + 6. For a native ELF linker, the directories in 'DT_RUNPATH' or + 'DT_RPATH' of a shared library are searched for shared + libraries needed by it. The 'DT_RPATH' entries are ignored if + 'DT_RUNPATH' entries exist. + 7. The default directories, normally '/lib' and '/usr/lib'. 8. For a native linker on an ELF system, if the file - `/etc/ld.so.conf' exists, the list of directories found in + '/etc/ld.so.conf' exists, the list of directories found in that file. If the required shared library is not found, the linker will issue a warning and continue with the link. -`-shared' -`-Bshareable' +'-shared' +'-Bshareable' Create a shared library. This is currently only supported on ELF, - XCOFF and SunOS platforms. On SunOS, the linker will - automatically create a shared library if the `-e' option is not - used and there are undefined symbols in the link. - -`--sort-common' -`--sort-common=ascending' -`--sort-common=descending' - This option tells `ld' to sort the common symbols by alignment in + XCOFF and SunOS platforms. On SunOS, the linker will automatically + create a shared library if the '-e' option is not used and there + are undefined symbols in the link. + +'--sort-common' +'--sort-common=ascending' +'--sort-common=descending' + This option tells 'ld' to sort the common symbols by alignment in ascending or descending order when it places them in the appropriate output sections. The symbol alignments considered are sixteen-byte or larger, eight-byte, four-byte, two-byte, and - one-byte. This is to prevent gaps between symbols due to alignment + one-byte. This is to prevent gaps between symbols due to alignment constraints. If no sorting order is specified, then descending order is assumed. -`--sort-section=name' - This option will apply `SORT_BY_NAME' to all wildcard section +'--sort-section=name' + This option will apply 'SORT_BY_NAME' to all wildcard section patterns in the linker script. -`--sort-section=alignment' - This option will apply `SORT_BY_ALIGNMENT' to all wildcard section +'--sort-section=alignment' + This option will apply 'SORT_BY_ALIGNMENT' to all wildcard section patterns in the linker script. -`--split-by-file[=SIZE]' - Similar to `--split-by-reloc' but creates a new output section for - each input file when SIZE is reached. SIZE defaults to a size of - 1 if not given. +'--split-by-file[=SIZE]' + Similar to '--split-by-reloc' but creates a new output section for + each input file when SIZE is reached. SIZE defaults to a size of 1 + if not given. -`--split-by-reloc[=COUNT]' +'--split-by-reloc[=COUNT]' Tries to creates extra sections in the output file so that no single output section in the file contains more than COUNT - relocations. This is useful when generating huge relocatable - files for downloading into certain real time kernels with the COFF - object file format; since COFF cannot represent more than 65535 + relocations. This is useful when generating huge relocatable files + for downloading into certain real time kernels with the COFF object + file format; since COFF cannot represent more than 65535 relocations in a single section. Note that this will fail to work with object file formats which do not support arbitrary sections. The linker will not split up individual input sections for @@ -1359,136 +1333,135 @@ GNU linker: COUNT relocations one output section will contain that many relocations. COUNT defaults to a value of 32768. -`--stats' +'--stats' Compute and display statistics about the operation of the linker, such as execution time and memory usage. -`--sysroot=DIRECTORY' +'--sysroot=DIRECTORY' Use DIRECTORY as the location of the sysroot, overriding the configure-time default. This option is only supported by linkers - that were configured using `--with-sysroot'. + that were configured using '--with-sysroot'. -`--traditional-format' - For some targets, the output of `ld' is different in some ways from - the output of some existing linker. This switch requests `ld' to +'--traditional-format' + For some targets, the output of 'ld' is different in some ways from + the output of some existing linker. This switch requests 'ld' to use the traditional format instead. - For example, on SunOS, `ld' combines duplicate entries in the + For example, on SunOS, 'ld' combines duplicate entries in the symbol string table. This can reduce the size of an output file - with full debugging information by over 30 percent. - Unfortunately, the SunOS `dbx' program can not read the resulting - program (`gdb' has no trouble). The `--traditional-format' switch - tells `ld' to not combine duplicate entries. + with full debugging information by over 30 percent. Unfortunately, + the SunOS 'dbx' program can not read the resulting program ('gdb' + has no trouble). The '--traditional-format' switch tells 'ld' to + not combine duplicate entries. -`--section-start=SECTIONNAME=ORG' +'--section-start=SECTIONNAME=ORG' Locate a section in the output file at the absolute address given by ORG. You may use this option as many times as necessary to - locate multiple sections in the command line. ORG must be a - single hexadecimal integer; for compatibility with other linkers, - you may omit the leading `0x' usually associated with hexadecimal - values. _Note:_ there should be no white space between - SECTIONNAME, the equals sign ("<=>"), and ORG. - -`-Tbss=ORG' -`-Tdata=ORG' -`-Ttext=ORG' - Same as `--section-start', with `.bss', `.data' or `.text' as the + locate multiple sections in the command line. ORG must be a single + hexadecimal integer; for compatibility with other linkers, you may + omit the leading '0x' usually associated with hexadecimal values. + _Note:_ there should be no white space between SECTIONNAME, the + equals sign ("<=>"), and ORG. + +'-Tbss=ORG' +'-Tdata=ORG' +'-Ttext=ORG' + Same as '--section-start', with '.bss', '.data' or '.text' as the SECTIONNAME. -`-Ttext-segment=ORG' +'-Ttext-segment=ORG' When creating an ELF executable or shared object, it will set the address of the first byte of the text segment. -`-Trodata-segment=ORG' +'-Trodata-segment=ORG' When creating an ELF executable or shared object for a target where the read-only data is in its own segment separate from the executable text, it will set the address of the first byte of the read-only data segment. -`-Tldata-segment=ORG' +'-Tldata-segment=ORG' When creating an ELF executable or shared object for x86-64 medium memory model, it will set the address of the first byte of the ldata segment. -`--unresolved-symbols=METHOD' +'--unresolved-symbols=METHOD' Determine how to handle unresolved symbols. There are four - possible values for `method': + possible values for 'method': - `ignore-all' + 'ignore-all' Do not report any unresolved symbols. - `report-all' + 'report-all' Report all unresolved symbols. This is the default. - `ignore-in-object-files' + 'ignore-in-object-files' Report unresolved symbols that are contained in shared libraries, but ignore them if they come from regular object files. - `ignore-in-shared-libs' - Report unresolved symbols that come from regular object - files, but ignore them if they come from shared libraries. - This can be useful when creating a dynamic binary and it is - known that all the shared libraries that it should be - referencing are included on the linker's command line. + 'ignore-in-shared-libs' + Report unresolved symbols that come from regular object files, + but ignore them if they come from shared libraries. This can + be useful when creating a dynamic binary and it is known that + all the shared libraries that it should be referencing are + included on the linker's command line. The behaviour for shared libraries on their own can also be - controlled by the `--[no-]allow-shlib-undefined' option. + controlled by the '--[no-]allow-shlib-undefined' option. Normally the linker will generate an error message for each reported unresolved symbol but the option - `--warn-unresolved-symbols' can change this to a warning. + '--warn-unresolved-symbols' can change this to a warning. -`--dll-verbose' -`--verbose[=NUMBER]' - Display the version number for `ld' and list the linker emulations +'--dll-verbose' +'--verbose[=NUMBER]' + Display the version number for 'ld' and list the linker emulations supported. Display which input files can and cannot be opened. - Display the linker script being used by the linker. If the + Display the linker script being used by the linker. If the optional NUMBER argument > 1, plugin symbol status will also be displayed. -`--version-script=VERSION-SCRIPTFILE' +'--version-script=VERSION-SCRIPTFILE' Specify the name of a version script to the linker. This is - typically used when creating shared libraries to specify - additional information about the version hierarchy for the library - being created. This option is only fully supported on ELF - platforms which support shared libraries; see *note VERSION::. It - is partially supported on PE platforms, which can use version - scripts to filter symbol visibility in auto-export mode: any - symbols marked `local' in the version script will not be exported. - *Note WIN32::. - -`--warn-common' - Warn when a common symbol is combined with another common symbol - or with a symbol definition. Unix linkers allow this somewhat - sloppy practice, but linkers on some other operating systems do - not. This option allows you to find potential problems from - combining global symbols. Unfortunately, some C libraries use - this practice, so you may get some warnings about symbols in the - libraries as well as in your programs. + typically used when creating shared libraries to specify additional + information about the version hierarchy for the library being + created. This option is only fully supported on ELF platforms + which support shared libraries; see *note VERSION::. It is + partially supported on PE platforms, which can use version scripts + to filter symbol visibility in auto-export mode: any symbols marked + 'local' in the version script will not be exported. *Note WIN32::. + +'--warn-common' + Warn when a common symbol is combined with another common symbol or + with a symbol definition. Unix linkers allow this somewhat sloppy + practice, but linkers on some other operating systems do not. This + option allows you to find potential problems from combining global + symbols. Unfortunately, some C libraries use this practice, so you + may get some warnings about symbols in the libraries as well as in + your programs. There are three kinds of global symbols, illustrated here by C examples: - `int i = 1;' + 'int i = 1;' A definition, which goes in the initialized data section of the output file. - `extern int i;' + 'extern int i;' An undefined reference, which does not allocate space. There must be either a definition or a common symbol for the variable somewhere. - `int i;' + 'int i;' A common symbol. If there are only (one or more) common - symbols for a variable, it goes in the uninitialized data - area of the output file. The linker merges multiple common - symbols for the same variable into a single symbol. If they - are of different sizes, it picks the largest size. The - linker turns a common symbol into a declaration, if there is - a definition of the same variable. - - The `--warn-common' option can produce five kinds of warnings. + symbols for a variable, it goes in the uninitialized data area + of the output file. The linker merges multiple common symbols + for the same variable into a single symbol. If they are of + different sizes, it picks the largest size. The linker turns + a common symbol into a declaration, if there is a definition + of the same variable. + + The '--warn-common' option can produce five kinds of warnings. Each warning consists of a pair of lines: the first describes the symbol just encountered, and the second describes the previous symbol encountered with the same name. One or both of the two @@ -1501,9 +1474,9 @@ GNU linker: FILE(SECTION): warning: defined here 2. Turning a common symbol into a reference, because a later - definition for the symbol is encountered. This is the same - as the previous case, except that the symbols are encountered - in a different order. + definition for the symbol is encountered. This is the same as + the previous case, except that the symbols are encountered in + a different order. FILE(SECTION): warning: definition of `SYMBOL' overriding common FILE(SECTION): warning: common is here @@ -1519,80 +1492,80 @@ GNU linker: overridden by larger common FILE(SECTION): warning: larger common is here - 5. Merging a common symbol with a previous smaller common - symbol. This is the same as the previous case, except that - the symbols are encountered in a different order. + 5. Merging a common symbol with a previous smaller common symbol. + This is the same as the previous case, except that the symbols + are encountered in a different order. FILE(SECTION): warning: common of `SYMBOL' overriding smaller common FILE(SECTION): warning: smaller common is here -`--warn-constructors' +'--warn-constructors' Warn if any global constructors are used. This is only useful for a few object file formats. For formats like COFF or ELF, the linker can not detect the use of global constructors. -`--warn-multiple-gp' +'--warn-multiple-gp' Warn if multiple global pointer values are required in the output file. This is only meaningful for certain processors, such as the - Alpha. Specifically, some processors put large-valued constants - in a special section. A special register (the global pointer) - points into the middle of this section, so that constants can be - loaded efficiently via a base-register relative addressing mode. - Since the offset in base-register relative mode is fixed and - relatively small (e.g., 16 bits), this limits the maximum size of - the constant pool. Thus, in large programs, it is often necessary - to use multiple global pointer values in order to be able to - address all possible constants. This option causes a warning to - be issued whenever this case occurs. - -`--warn-once' + Alpha. Specifically, some processors put large-valued constants in + a special section. A special register (the global pointer) points + into the middle of this section, so that constants can be loaded + efficiently via a base-register relative addressing mode. Since + the offset in base-register relative mode is fixed and relatively + small (e.g., 16 bits), this limits the maximum size of the constant + pool. Thus, in large programs, it is often necessary to use + multiple global pointer values in order to be able to address all + possible constants. This option causes a warning to be issued + whenever this case occurs. + +'--warn-once' Only warn once for each undefined symbol, rather than once per module which refers to it. -`--warn-section-align' +'--warn-section-align' Warn if the address of an output section is changed because of alignment. Typically, the alignment will be set by an input section. The address will only be changed if it not explicitly - specified; that is, if the `SECTIONS' command does not specify a + specified; that is, if the 'SECTIONS' command does not specify a start address for the section (*note SECTIONS::). -`--warn-shared-textrel' +'--warn-shared-textrel' Warn if the linker adds a DT_TEXTREL to a shared object. -`--warn-alternate-em' +'--warn-alternate-em' Warn if an object has alternate ELF machine code. -`--warn-unresolved-symbols' +'--warn-unresolved-symbols' If the linker is going to report an unresolved symbol (see the - option `--unresolved-symbols') it will normally generate an error. + option '--unresolved-symbols') it will normally generate an error. This option makes it generate a warning instead. -`--error-unresolved-symbols' +'--error-unresolved-symbols' This restores the linker's default behaviour of generating errors when it is reporting unresolved symbols. -`--whole-archive' +'--whole-archive' For each archive mentioned on the command line after the - `--whole-archive' option, include every object file in the archive + '--whole-archive' option, include every object file in the archive in the link, rather than searching the archive for the required - object files. This is normally used to turn an archive file into - a shared library, forcing every object to be included in the + object files. This is normally used to turn an archive file into a + shared library, forcing every object to be included in the resulting shared library. This option may be used more than once. Two notes when using this option from gcc: First, gcc doesn't know - about this option, so you have to use `-Wl,-whole-archive'. - Second, don't forget to use `-Wl,-no-whole-archive' after your - list of archives, because gcc will add its own list of archives to - your link and you may not want this flag to affect those as well. + about this option, so you have to use '-Wl,-whole-archive'. + Second, don't forget to use '-Wl,-no-whole-archive' after your list + of archives, because gcc will add its own list of archives to your + link and you may not want this flag to affect those as well. -`--wrap=SYMBOL' +'--wrap=SYMBOL' Use a wrapper function for SYMBOL. Any undefined reference to - SYMBOL will be resolved to `__wrap_SYMBOL'. Any undefined - reference to `__real_SYMBOL' will be resolved to SYMBOL. + SYMBOL will be resolved to '__wrap_SYMBOL'. Any undefined + reference to '__real_SYMBOL' will be resolved to SYMBOL. This can be used to provide a wrapper for a system function. The - wrapper function should be called `__wrap_SYMBOL'. If it wishes - to call the system function, it should call `__real_SYMBOL'. + wrapper function should be called '__wrap_SYMBOL'. If it wishes to + call the system function, it should call '__real_SYMBOL'. Here is a trivial example: @@ -1603,37 +1576,37 @@ GNU linker: return __real_malloc (c); } - If you link other code with this file using `--wrap malloc', then - all calls to `malloc' will call the function `__wrap_malloc' - instead. The call to `__real_malloc' in `__wrap_malloc' will call - the real `malloc' function. + If you link other code with this file using '--wrap malloc', then + all calls to 'malloc' will call the function '__wrap_malloc' + instead. The call to '__real_malloc' in '__wrap_malloc' will call + the real 'malloc' function. - You may wish to provide a `__real_malloc' function as well, so that - links without the `--wrap' option will succeed. If you do this, - you should not put the definition of `__real_malloc' in the same - file as `__wrap_malloc'; if you do, the assembler may resolve the - call before the linker has a chance to wrap it to `malloc'. + You may wish to provide a '__real_malloc' function as well, so that + links without the '--wrap' option will succeed. If you do this, + you should not put the definition of '__real_malloc' in the same + file as '__wrap_malloc'; if you do, the assembler may resolve the + call before the linker has a chance to wrap it to 'malloc'. -`--eh-frame-hdr' - Request creation of `.eh_frame_hdr' section and ELF - `PT_GNU_EH_FRAME' segment header. +'--eh-frame-hdr' + Request creation of '.eh_frame_hdr' section and ELF + 'PT_GNU_EH_FRAME' segment header. -`--no-ld-generated-unwind-info' - Request creation of `.eh_frame' unwind info for linker generated - code sections like PLT. This option is on by default if linker +'--no-ld-generated-unwind-info' + Request creation of '.eh_frame' unwind info for linker generated + code sections like PLT. This option is on by default if linker generated unwind info is supported. -`--enable-new-dtags' -`--disable-new-dtags' +'--enable-new-dtags' +'--disable-new-dtags' This linker can create the new dynamic tags in ELF. But the older - ELF systems may not understand them. If you specify - `--enable-new-dtags', the new dynamic tags will be created as + ELF systems may not understand them. If you specify + '--enable-new-dtags', the new dynamic tags will be created as needed and older dynamic tags will be omitted. If you specify - `--disable-new-dtags', no new dynamic tags will be created. By - default, the new dynamic tags are not created. Note that those + '--disable-new-dtags', no new dynamic tags will be created. By + default, the new dynamic tags are not created. Note that those options are only available for ELF systems. -`--hash-size=NUMBER' +'--hash-size=NUMBER' Set the default size of the linker's hash tables to a prime number close to NUMBER. Increasing this value can reduce the length of time it takes the linker to perform its tasks, at the expense of @@ -1641,13 +1614,13 @@ GNU linker: this value can reduce the memory requirements at the expense of speed. -`--hash-style=STYLE' - Set the type of linker's hash table(s). STYLE can be either - `sysv' for classic ELF `.hash' section, `gnu' for new style GNU - `.gnu.hash' section or `both' for both the classic ELF `.hash' and - new style GNU `.gnu.hash' hash tables. The default is `sysv'. +'--hash-style=STYLE' + Set the type of linker's hash table(s). STYLE can be either 'sysv' + for classic ELF '.hash' section, 'gnu' for new style GNU + '.gnu.hash' section or 'both' for both the classic ELF '.hash' and + new style GNU '.gnu.hash' hash tables. The default is 'sysv'. -`--reduce-memory-overheads' +'--reduce-memory-overheads' This option reduces memory requirements at ld runtime, at the expense of linking speed. This was introduced to select the old O(n^2) algorithm for link map file generation, rather than the new @@ -1655,159 +1628,158 @@ GNU linker: Another effect of the switch is to set the default hash table size to 1021, which again saves memory at the cost of lengthening the - linker's run time. This is not done however if the `--hash-size' + linker's run time. This is not done however if the '--hash-size' switch has been used. - The `--reduce-memory-overheads' switch may be also be used to + The '--reduce-memory-overheads' switch may be also be used to enable other tradeoffs in future versions of the linker. -`--build-id' -`--build-id=STYLE' - Request creation of `.note.gnu.build-id' ELF note section. The +'--build-id' +'--build-id=STYLE' + Request creation of '.note.gnu.build-id' ELF note section. The contents of the note are unique bits identifying this linked file. - STYLE can be `uuid' to use 128 random bits, `sha1' to use a - 160-bit SHA1 hash on the normative parts of the output contents, - `md5' to use a 128-bit MD5 hash on the normative parts of the - output contents, or `0xHEXSTRING' to use a chosen bit string - specified as an even number of hexadecimal digits (`-' and `:' - characters between digit pairs are ignored). If STYLE is omitted, - `sha1' is used. - - The `md5' and `sha1' styles produces an identifier that is always + STYLE can be 'uuid' to use 128 random bits, 'sha1' to use a 160-bit + SHA1 hash on the normative parts of the output contents, 'md5' to + use a 128-bit MD5 hash on the normative parts of the output + contents, or '0xHEXSTRING' to use a chosen bit string specified as + an even number of hexadecimal digits ('-' and ':' characters + between digit pairs are ignored). If STYLE is omitted, 'sha1' is + used. + + The 'md5' and 'sha1' styles produces an identifier that is always the same in an identical output file, but will be unique among all nonidentical output files. It is not intended to be compared as a checksum for the file's contents. A linked file may be changed later by other tools, but the build ID bit string identifying the original linked file does not change. - Passing `none' for STYLE disables the setting from any - `--build-id' options earlier on the command line. + Passing 'none' for STYLE disables the setting from any '--build-id' + options earlier on the command line. 2.1.1 Options Specific to i386 PE Targets ----------------------------------------- -The i386 PE linker supports the `-shared' option, which causes the +The i386 PE linker supports the '-shared' option, which causes the output to be a dynamically linked library (DLL) instead of a normal -executable. You should name the output `*.dll' when you use this -option. In addition, the linker fully supports the standard `*.def' +executable. You should name the output '*.dll' when you use this +option. In addition, the linker fully supports the standard '*.def' files, which may be specified on the linker command line like an object file (in fact, it should precede archives it exports symbols from, to ensure that they get linked in, just like a normal object file). In addition to the options common to all targets, the i386 PE linker -support additional command line options that are specific to the i386 -PE target. Options that take values may be separated from their values -by either a space or an equals sign. +support additional command line options that are specific to the i386 PE +target. Options that take values may be separated from their values by +either a space or an equals sign. -`--add-stdcall-alias' +'--add-stdcall-alias' If given, symbols with a stdcall suffix (@NN) will be exported as-is and also with the suffix stripped. [This option is specific to the i386 PE targeted port of the linker] -`--base-file FILE' +'--base-file FILE' Use FILE as the name of a file in which to save the base addresses - of all the relocations needed for generating DLLs with `dlltool'. + of all the relocations needed for generating DLLs with 'dlltool'. [This is an i386 PE specific option] -`--dll' +'--dll' Create a DLL instead of a regular executable. You may also use - `-shared' or specify a `LIBRARY' in a given `.def' file. [This + '-shared' or specify a 'LIBRARY' in a given '.def' file. [This option is specific to the i386 PE targeted port of the linker] -`--enable-long-section-names' -`--disable-long-section-names' +'--enable-long-section-names' +'--disable-long-section-names' The PE variants of the Coff object format add an extension that permits the use of section names longer than eight characters, the - normal limit for Coff. By default, these names are only allowed - in object files, as fully-linked executable images do not carry - the Coff string table required to support the longer names. As a - GNU extension, it is possible to allow their use in executable - images as well, or to (probably pointlessly!) disallow it in - object files, by using these two options. Executable images - generated with these long section names are slightly non-standard, - carrying as they do a string table, and may generate confusing - output when examined with non-GNU PE-aware tools, such as file - viewers and dumpers. However, GDB relies on the use of PE long - section names to find Dwarf-2 debug information sections in an - executable image at runtime, and so if neither option is specified - on the command-line, `ld' will enable long section names, - overriding the default and technically correct behaviour, when it - finds the presence of debug information while linking an executable - image and not stripping symbols. [This option is valid for all PE - targeted ports of the linker] - -`--enable-stdcall-fixup' -`--disable-stdcall-fixup' + normal limit for Coff. By default, these names are only allowed in + object files, as fully-linked executable images do not carry the + Coff string table required to support the longer names. As a GNU + extension, it is possible to allow their use in executable images + as well, or to (probably pointlessly!) disallow it in object + files, by using these two options. Executable images generated + with these long section names are slightly non-standard, carrying + as they do a string table, and may generate confusing output when + examined with non-GNU PE-aware tools, such as file viewers and + dumpers. However, GDB relies on the use of PE long section names + to find Dwarf-2 debug information sections in an executable image + at runtime, and so if neither option is specified on the + command-line, 'ld' will enable long section names, overriding the + default and technically correct behaviour, when it finds the + presence of debug information while linking an executable image and + not stripping symbols. [This option is valid for all PE targeted + ports of the linker] + +'--enable-stdcall-fixup' +'--disable-stdcall-fixup' If the link finds a symbol that it cannot resolve, it will attempt to do "fuzzy linking" by looking for another defined symbol that differs only in the format of the symbol name (cdecl vs stdcall) - and will resolve that symbol by linking to the match. For - example, the undefined symbol `_foo' might be linked to the - function `_foo@12', or the undefined symbol `_bar@16' might be - linked to the function `_bar'. When the linker does this, it - prints a warning, since it normally should have failed to link, - but sometimes import libraries generated from third-party dlls may - need this feature to be usable. If you specify - `--enable-stdcall-fixup', this feature is fully enabled and - warnings are not printed. If you specify - `--disable-stdcall-fixup', this feature is disabled and such + and will resolve that symbol by linking to the match. For example, + the undefined symbol '_foo' might be linked to the function + '_foo@12', or the undefined symbol '_bar@16' might be linked to the + function '_bar'. When the linker does this, it prints a warning, + since it normally should have failed to link, but sometimes import + libraries generated from third-party dlls may need this feature to + be usable. If you specify '--enable-stdcall-fixup', this feature + is fully enabled and warnings are not printed. If you specify + '--disable-stdcall-fixup', this feature is disabled and such mismatches are considered to be errors. [This option is specific to the i386 PE targeted port of the linker] -`--leading-underscore' -`--no-leading-underscore' +'--leading-underscore' +'--no-leading-underscore' For most targets default symbol-prefix is an underscore and is - defined in target's description. By this option it is possible to + defined in target's description. By this option it is possible to disable/enable the default underscore symbol-prefix. -`--export-all-symbols' +'--export-all-symbols' If given, all global symbols in the objects used to build a DLL - will be exported by the DLL. Note that this is the default if - there otherwise wouldn't be any exported symbols. When symbols are + will be exported by the DLL. Note that this is the default if there + otherwise wouldn't be any exported symbols. When symbols are explicitly exported via DEF files or implicitly exported via function attributes, the default is to not export anything else - unless this option is given. Note that the symbols `DllMain@12', - `DllEntryPoint@0', `DllMainCRTStartup@12', and `impure_ptr' will + unless this option is given. Note that the symbols 'DllMain@12', + 'DllEntryPoint@0', 'DllMainCRTStartup@12', and 'impure_ptr' will not be automatically exported. Also, symbols imported from other - DLLs will not be re-exported, nor will symbols specifying the - DLL's internal layout such as those beginning with `_head_' or - ending with `_iname'. In addition, no symbols from `libgcc', - `libstd++', `libmingw32', or `crtX.o' will be exported. Symbols - whose names begin with `__rtti_' or `__builtin_' will not be - exported, to help with C++ DLLs. Finally, there is an extensive - list of cygwin-private symbols that are not exported (obviously, - this applies on when building DLLs for cygwin targets). These - cygwin-excludes are: `_cygwin_dll_entry@12', - `_cygwin_crt0_common@8', `_cygwin_noncygwin_dll_entry@12', - `_fmode', `_impure_ptr', `cygwin_attach_dll', `cygwin_premain0', - `cygwin_premain1', `cygwin_premain2', `cygwin_premain3', and - `environ'. [This option is specific to the i386 PE targeted port + DLLs will not be re-exported, nor will symbols specifying the DLL's + internal layout such as those beginning with '_head_' or ending + with '_iname'. In addition, no symbols from 'libgcc', 'libstd++', + 'libmingw32', or 'crtX.o' will be exported. Symbols whose names + begin with '__rtti_' or '__builtin_' will not be exported, to help + with C++ DLLs. Finally, there is an extensive list of + cygwin-private symbols that are not exported (obviously, this + applies on when building DLLs for cygwin targets). These + cygwin-excludes are: '_cygwin_dll_entry@12', + '_cygwin_crt0_common@8', '_cygwin_noncygwin_dll_entry@12', + '_fmode', '_impure_ptr', 'cygwin_attach_dll', 'cygwin_premain0', + 'cygwin_premain1', 'cygwin_premain2', 'cygwin_premain3', and + 'environ'. [This option is specific to the i386 PE targeted port of the linker] -`--exclude-symbols SYMBOL,SYMBOL,...' +'--exclude-symbols SYMBOL,SYMBOL,...' Specifies a list of symbols which should not be automatically exported. The symbol names may be delimited by commas or colons. [This option is specific to the i386 PE targeted port of the linker] -`--exclude-all-symbols' +'--exclude-all-symbols' Specifies no symbols should be automatically exported. [This option is specific to the i386 PE targeted port of the linker] -`--file-alignment' - Specify the file alignment. Sections in the file will always - begin at file offsets which are multiples of this number. This - defaults to 512. [This option is specific to the i386 PE targeted - port of the linker] +'--file-alignment' + Specify the file alignment. Sections in the file will always begin + at file offsets which are multiples of this number. This defaults + to 512. [This option is specific to the i386 PE targeted port of + the linker] -`--heap RESERVE' -`--heap RESERVE,COMMIT' +'--heap RESERVE' +'--heap RESERVE,COMMIT' Specify the number of bytes of memory to reserve (and optionally - commit) to be used as heap for this program. The default is 1Mb + commit) to be used as heap for this program. The default is 1MB reserved, 4K committed. [This option is specific to the i386 PE targeted port of the linker] -`--image-base VALUE' +'--image-base VALUE' Use VALUE as the base address of your program or dll. This is the lowest memory location that will be used when your program or dll is loaded. To reduce the need to relocate and improve performance @@ -1816,94 +1788,100 @@ by either a space or an equals sign. and 0x10000000 for dlls. [This option is specific to the i386 PE targeted port of the linker] -`--kill-at' +'--kill-at' If given, the stdcall suffixes (@NN) will be stripped from symbols before they are exported. [This option is specific to the i386 PE targeted port of the linker] -`--large-address-aware' - If given, the appropriate bit in the "Characteristics" field of - the COFF header is set to indicate that this executable supports - virtual addresses greater than 2 gigabytes. This should be used - in conjunction with the /3GB or /USERVA=VALUE megabytes switch in - the "[operating systems]" section of the BOOT.INI. Otherwise, - this bit has no effect. [This option is specific to PE targeted - ports of the linker] +'--large-address-aware' + If given, the appropriate bit in the "Characteristics" field of the + COFF header is set to indicate that this executable supports + virtual addresses greater than 2 gigabytes. This should be used in + conjunction with the /3GB or /USERVA=VALUE megabytes switch in the + "[operating systems]" section of the BOOT.INI. Otherwise, this bit + has no effect. [This option is specific to PE targeted ports of + the linker] + +'--disable-large-address-aware' + Reverts the effect of a previous '--large-address-aware' option. + This is useful if '--large-address-aware' is always set by the + compiler driver (e.g. Cygwin gcc) and the executable does not + support virtual addresses greater than 2 gigabytes. [This option + is specific to PE targeted ports of the linker] -`--major-image-version VALUE' +'--major-image-version VALUE' Sets the major number of the "image version". Defaults to 1. [This option is specific to the i386 PE targeted port of the linker] -`--major-os-version VALUE' +'--major-os-version VALUE' Sets the major number of the "os version". Defaults to 4. [This option is specific to the i386 PE targeted port of the linker] -`--major-subsystem-version VALUE' +'--major-subsystem-version VALUE' Sets the major number of the "subsystem version". Defaults to 4. [This option is specific to the i386 PE targeted port of the linker] -`--minor-image-version VALUE' +'--minor-image-version VALUE' Sets the minor number of the "image version". Defaults to 0. [This option is specific to the i386 PE targeted port of the linker] -`--minor-os-version VALUE' +'--minor-os-version VALUE' Sets the minor number of the "os version". Defaults to 0. [This option is specific to the i386 PE targeted port of the linker] -`--minor-subsystem-version VALUE' +'--minor-subsystem-version VALUE' Sets the minor number of the "subsystem version". Defaults to 0. [This option is specific to the i386 PE targeted port of the linker] -`--output-def FILE' +'--output-def FILE' The linker will create the file FILE which will contain a DEF file corresponding to the DLL the linker is generating. This DEF file - (which should be called `*.def') may be used to create an import - library with `dlltool' or may be used as a reference to + (which should be called '*.def') may be used to create an import + library with 'dlltool' or may be used as a reference to automatically or implicitly exported symbols. [This option is specific to the i386 PE targeted port of the linker] -`--out-implib FILE' +'--out-implib FILE' The linker will create the file FILE which will contain an import - lib corresponding to the DLL the linker is generating. This import - lib (which should be called `*.dll.a' or `*.a' may be used to link - clients against the generated DLL; this behaviour makes it - possible to skip a separate `dlltool' import library creation step. - [This option is specific to the i386 PE targeted port of the - linker] + lib corresponding to the DLL the linker is generating. This import + lib (which should be called '*.dll.a' or '*.a' may be used to link + clients against the generated DLL; this behaviour makes it possible + to skip a separate 'dlltool' import library creation step. [This + option is specific to the i386 PE targeted port of the linker] -`--enable-auto-image-base' +'--enable-auto-image-base' Automatically choose the image base for DLLs, unless one is - specified using the `--image-base' argument. By using a hash + specified using the '--image-base' argument. By using a hash generated from the dllname to create unique image bases for each DLL, in-memory collisions and relocations which can delay program execution are avoided. [This option is specific to the i386 PE targeted port of the linker] -`--disable-auto-image-base' +'--disable-auto-image-base' Do not automatically generate a unique image base. If there is no - user-specified image base (`--image-base') then use the platform + user-specified image base ('--image-base') then use the platform default. [This option is specific to the i386 PE targeted port of the linker] -`--dll-search-prefix STRING' - When linking dynamically to a dll without an import library, - search for `<string><basename>.dll' in preference to - `lib<basename>.dll'. This behaviour allows easy distinction - between DLLs built for the various "subplatforms": native, cygwin, - uwin, pw, etc. For instance, cygwin DLLs typically use - `--dll-search-prefix=cyg'. [This option is specific to the i386 - PE targeted port of the linker] - -`--enable-auto-import' - Do sophisticated linking of `_symbol' to `__imp__symbol' for DATA +'--dll-search-prefix STRING' + When linking dynamically to a dll without an import library, search + for '<string><basename>.dll' in preference to 'lib<basename>.dll'. + This behaviour allows easy distinction between DLLs built for the + various "subplatforms": native, cygwin, uwin, pw, etc. For + instance, cygwin DLLs typically use '--dll-search-prefix=cyg'. + [This option is specific to the i386 PE targeted port of the + linker] + +'--enable-auto-import' + Do sophisticated linking of '_symbol' to '__imp__symbol' for DATA imports from DLLs, and create the necessary thunking symbols when - building the import libraries with those DATA exports. Note: Use + building the import libraries with those DATA exports. Note: Use of the 'auto-import' extension will cause the text section of the - image file to be made writable. This does not conform to the + image file to be made writable. This does not conform to the PE-COFF format specification published by Microsoft. Note - use of the 'auto-import' extension will also cause read only @@ -1915,23 +1893,23 @@ by either a space or an equals sign. Using 'auto-import' generally will 'just work' - but sometimes you may see this message: - "variable '<var>' can't be auto-imported. Please read the - documentation for ld's `--enable-auto-import' for details." + "variable '<var>' can't be auto-imported. Please read the + documentation for ld's '--enable-auto-import' for details." This message occurs when some (sub)expression accesses an address ultimately given by the sum of two constants (Win32 import tables only allow one). Instances where this may occur include accesses to member fields of struct variables imported from a DLL, as well as using a constant index into an array variable imported from a - DLL. Any multiword variable (arrays, structs, long long, etc) may + DLL. Any multiword variable (arrays, structs, long long, etc) may trigger this error condition. However, regardless of the exact - data type of the offending exported variable, ld will always - detect it, issue the warning, and exit. + data type of the offending exported variable, ld will always detect + it, issue the warning, and exit. There are several ways to address this difficulty, regardless of the data type of the exported variable: - One way is to use -enable-runtime-pseudo-reloc switch. This leaves + One way is to use -enable-runtime-pseudo-reloc switch. This leaves the task of adjusting references in your client code for runtime environment, so this method works only when runtime environment supports this feature. @@ -1968,13 +1946,12 @@ by either a space or an equals sign. A third method of dealing with this difficulty is to abandon 'auto-import' for the offending symbol and mark it with - `__declspec(dllimport)'. However, in practice that requires using + '__declspec(dllimport)'. However, in practice that requires using compile-time #defines to indicate whether you are building a DLL, building client code that will link to the DLL, or merely - building/linking to a static library. In making the choice - between the various methods of resolving the 'direct address with - constant offset' problem, you should consider typical real-world - usage: + building/linking to a static library. In making the choice between + the various methods of resolving the 'direct address with constant + offset' problem, you should consider typical real-world usage: Original: --foo.h @@ -2014,16 +1991,16 @@ by either a space or an equals sign. A fourth way to avoid this problem is to re-code your library to use a functional interface rather than a data interface for the - offending variables (e.g. set_foo() and get_foo() accessor + offending variables (e.g. set_foo() and get_foo() accessor functions). [This option is specific to the i386 PE targeted port of the linker] -`--disable-auto-import' - Do not attempt to do sophisticated linking of `_symbol' to - `__imp__symbol' for DATA imports from DLLs. [This option is +'--disable-auto-import' + Do not attempt to do sophisticated linking of '_symbol' to + '__imp__symbol' for DATA imports from DLLs. [This option is specific to the i386 PE targeted port of the linker] -`--enable-runtime-pseudo-reloc' +'--enable-runtime-pseudo-reloc' If your code contains expressions described in -enable-auto-import section, that is, DATA imports from DLL with non-zero offset, this switch will create a vector of 'runtime pseudo relocations' which @@ -2031,70 +2008,75 @@ by either a space or an equals sign. data in your client code. [This option is specific to the i386 PE targeted port of the linker] -`--disable-runtime-pseudo-reloc' +'--disable-runtime-pseudo-reloc' Do not create pseudo relocations for non-zero offset DATA imports from DLLs. [This option is specific to the i386 PE targeted port of the linker] -`--enable-extra-pe-debug' +'--enable-extra-pe-debug' Show additional debug info related to auto-import symbol thunking. [This option is specific to the i386 PE targeted port of the linker] -`--section-alignment' +'--section-alignment' Sets the section alignment. Sections in memory will always begin at addresses which are a multiple of this number. Defaults to 0x1000. [This option is specific to the i386 PE targeted port of the linker] -`--stack RESERVE' -`--stack RESERVE,COMMIT' +'--stack RESERVE' +'--stack RESERVE,COMMIT' Specify the number of bytes of memory to reserve (and optionally - commit) to be used as stack for this program. The default is 2Mb + commit) to be used as stack for this program. The default is 2MB reserved, 4K committed. [This option is specific to the i386 PE targeted port of the linker] -`--subsystem WHICH' -`--subsystem WHICH:MAJOR' -`--subsystem WHICH:MAJOR.MINOR' +'--subsystem WHICH' +'--subsystem WHICH:MAJOR' +'--subsystem WHICH:MAJOR.MINOR' Specifies the subsystem under which your program will execute. The - legal values for WHICH are `native', `windows', `console', - `posix', and `xbox'. You may optionally set the subsystem version - also. Numeric values are also accepted for WHICH. [This option - is specific to the i386 PE targeted port of the linker] + legal values for WHICH are 'native', 'windows', 'console', 'posix', + and 'xbox'. You may optionally set the subsystem version also. + Numeric values are also accepted for WHICH. [This option is + specific to the i386 PE targeted port of the linker] - The following options set flags in the `DllCharacteristics' field + The following options set flags in the 'DllCharacteristics' field of the PE file header: [These options are specific to PE targeted ports of the linker] -`--dynamicbase' +'--dynamicbase' The image base address may be relocated using address space layout - randomization (ASLR). This feature was introduced with MS Windows + randomization (ASLR). This feature was introduced with MS Windows Vista for i386 PE targets. -`--forceinteg' +'--forceinteg' Code integrity checks are enforced. -`--nxcompat' +'--nxcompat' The image is compatible with the Data Execution Prevention. This feature was introduced with MS Windows XP SP2 for i386 PE targets. -`--no-isolation' +'--no-isolation' Although the image understands isolation, do not isolate the image. -`--no-seh' +'--no-seh' The image does not use SEH. No SE handler may be called from this image. -`--no-bind' +'--no-bind' Do not bind this image. -`--wdmdriver' +'--wdmdriver' The driver uses the MS Windows Driver Model. -`--tsaware' +'--tsaware' The image is Terminal Server aware. +'--insert-timestamp' + Insert a real timestamp into the image, rather than the default + value of zero. This will result in a slightly different results + with each invocation, which could be helpful for distributing + unique images. 2.1.2 Options specific to C6X uClinux targets --------------------------------------------- @@ -2103,52 +2085,64 @@ The C6X uClinux target uses a binary format called DSBT to support shared libraries. Each shared library in the system needs to have a unique index; all executables use an index of 0. -`--dsbt-size SIZE' +'--dsbt-size SIZE' This option sets the number of entires in the DSBT of the current executable or shared library to SIZE. The default is to create a table with 64 entries. -`--dsbt-index INDEX' - This option sets the DSBT index of the current executable or - shared library to INDEX. The default is 0, which is appropriate - for generating executables. If a shared library is generated with - a DSBT index of 0, the `R_C6000_DSBT_INDEX' relocs are copied into +'--dsbt-index INDEX' + This option sets the DSBT index of the current executable or shared + library to INDEX. The default is 0, which is appropriate for + generating executables. If a shared library is generated with a + DSBT index of 0, the 'R_C6000_DSBT_INDEX' relocs are copied into the output file. - The `--no-merge-exidx-entries' switch disables the merging of + The '--no-merge-exidx-entries' switch disables the merging of adjacent exidx entries in frame unwind info. - 2.1.3 Options specific to Motorola 68HC11 and 68HC12 targets ------------------------------------------------------------ The 68HC11 and 68HC12 linkers support specific options to control the memory bank switching mapping and trampoline code generation. -`--no-trampoline' - This option disables the generation of trampoline. By default a - trampoline is generated for each far function which is called - using a `jsr' instruction (this happens when a pointer to a far - function is taken). +'--no-trampoline' + This option disables the generation of trampoline. By default a + trampoline is generated for each far function which is called using + a 'jsr' instruction (this happens when a pointer to a far function + is taken). -`--bank-window NAME' +'--bank-window NAME' This option indicates to the linker the name of the memory region - in the `MEMORY' specification that describes the memory bank + in the 'MEMORY' specification that describes the memory bank window. The definition of such region is then used by the linker to compute paging and addresses within the memory window. - 2.1.4 Options specific to Motorola 68K target --------------------------------------------- The following options are supported to control handling of GOT generation when linking for 68K targets. -`--got=TYPE' +'--got=TYPE' This option tells the linker which GOT generation scheme to use. - TYPE should be one of `single', `negative', `multigot' or - `target'. For more information refer to the Info entry for `ld'. + TYPE should be one of 'single', 'negative', 'multigot' or 'target'. + For more information refer to the Info entry for 'ld'. + +2.1.5 Options specific to MIPS targets +-------------------------------------- +The following options are supported to control microMIPS instruction +generation when linking for MIPS targets. + +'--insn32' +'--no-insn32' + These options control the choice of microMIPS instructions used in + code generated by the linker, such as that in the PLT or lazy + binding stubs, or in relaxation. If '--insn32' is used, then the + linker only uses 32-bit instruction encodings. By default or if + '--no-insn32' is used, all instruction encodings are used, + including 16-bit ones where possible. File: ld.info, Node: Environment, Prev: Options, Up: Invocation @@ -2156,14 +2150,14 @@ File: ld.info, Node: Environment, Prev: Options, Up: Invocation 2.2 Environment Variables ========================= -You can change the behaviour of `ld' with the environment variables -`GNUTARGET', `LDEMULATION' and `COLLECT_NO_DEMANGLE'. +You can change the behaviour of 'ld' with the environment variables +'GNUTARGET', 'LDEMULATION' and 'COLLECT_NO_DEMANGLE'. - `GNUTARGET' determines the input-file object format if you don't use -`-b' (or its synonym `--format'). Its value should be one of the BFD -names for an input format (*note BFD::). If there is no `GNUTARGET' in -the environment, `ld' uses the natural format of the target. If -`GNUTARGET' is set to `default' then BFD attempts to discover the input + 'GNUTARGET' determines the input-file object format if you don't use +'-b' (or its synonym '--format'). Its value should be one of the BFD +names for an input format (*note BFD::). If there is no 'GNUTARGET' in +the environment, 'ld' uses the natural format of the target. If +'GNUTARGET' is set to 'default' then BFD attempts to discover the input format by examining binary input files; this method often succeeds, but there are potential ambiguities, since there is no method of ensuring that the magic number used to specify object-file formats is unique. @@ -2171,19 +2165,19 @@ However, the configuration procedure for BFD on each system places the conventional format for that system first in the search-list, so ambiguities are resolved in favor of convention. - `LDEMULATION' determines the default emulation if you don't use the -`-m' option. The emulation can affect various aspects of linker + 'LDEMULATION' determines the default emulation if you don't use the +'-m' option. The emulation can affect various aspects of linker behaviour, particularly the default linker script. You can list the -available emulations with the `--verbose' or `-V' options. If the `-m' -option is not used, and the `LDEMULATION' environment variable is not +available emulations with the '--verbose' or '-V' options. If the '-m' +option is not used, and the 'LDEMULATION' environment variable is not defined, the default emulation depends upon how the linker was configured. Normally, the linker will default to demangling symbols. However, if -`COLLECT_NO_DEMANGLE' is set in the environment, then it will default -to not demangling symbols. This environment variable is used in a -similar fashion by the `gcc' linker wrapper program. The default may -be overridden by the `--demangle' and `--no-demangle' options. +'COLLECT_NO_DEMANGLE' is set in the environment, then it will default to +not demangling symbols. This environment variable is used in a similar +fashion by the 'gcc' linker wrapper program. The default may be +overridden by the '--demangle' and '--no-demangle' options. File: ld.info, Node: Scripts, Next: Machine Dependent, Prev: Invocation, Up: Top @@ -2194,20 +2188,20 @@ File: ld.info, Node: Scripts, Next: Machine Dependent, Prev: Invocation, Up: Every link is controlled by a "linker script". This script is written in the linker command language. - The main purpose of the linker script is to describe how the -sections in the input files should be mapped into the output file, and -to control the memory layout of the output file. Most linker scripts -do nothing more than this. However, when necessary, the linker script -can also direct the linker to perform many other operations, using the -commands described below. + The main purpose of the linker script is to describe how the sections +in the input files should be mapped into the output file, and to control +the memory layout of the output file. Most linker scripts do nothing +more than this. However, when necessary, the linker script can also +direct the linker to perform many other operations, using the commands +described below. The linker always uses a linker script. If you do not supply one yourself, the linker will use a default script that is compiled into the -linker executable. You can use the `--verbose' command line option to +linker executable. You can use the '--verbose' command line option to display the default linker script. Certain command line options, such -as `-r' or `-N', will affect the default linker script. +as '-r' or '-N', will affect the default linker script. - You may supply your own linker script by using the `-T' command line + You may supply your own linker script by using the '-T' command line option. When you do this, your linker script will replace the default linker script. @@ -2240,12 +2234,12 @@ describe the linker script language. The linker combines input files into a single output file. The output file and each input file are in a special data format known as an -"object file format". Each file is called an "object file". The -output file is often called an "executable", but for our purposes we -will also call it an object file. Each object file has, among other -things, a list of "sections". We sometimes refer to a section in an -input file as an "input section"; similarly, a section in the output -file is an "output section". +"object file format". Each file is called an "object file". The output +file is often called an "executable", but for our purposes we will also +call it an object file. Each object file has, among other things, a +list of "sections". We sometimes refer to a section in an input file as +an "input section"; similarly, a section in the output file is an +"output section". Each section in an object file has a name and a size. Most sections also have an associated block of data, known as the "section contents". @@ -2259,28 +2253,28 @@ debugging information. Every loadable or allocatable output section has two addresses. The first is the "VMA", or virtual memory address. This is the address the -section will have when the output file is run. The second is the -"LMA", or load memory address. This is the address at which the -section will be loaded. In most cases the two addresses will be the -same. An example of when they might be different is when a data section -is loaded into ROM, and then copied into RAM when the program starts up -(this technique is often used to initialize global variables in a ROM -based system). In this case the ROM address would be the LMA, and the -RAM address would be the VMA. - - You can see the sections in an object file by using the `objdump' -program with the `-h' option. +section will have when the output file is run. The second is the "LMA", +or load memory address. This is the address at which the section will +be loaded. In most cases the two addresses will be the same. An +example of when they might be different is when a data section is loaded +into ROM, and then copied into RAM when the program starts up (this +technique is often used to initialize global variables in a ROM based +system). In this case the ROM address would be the LMA, and the RAM +address would be the VMA. + + You can see the sections in an object file by using the 'objdump' +program with the '-h' option. Every object file also has a list of "symbols", known as the "symbol table". A symbol may be defined or undefined. Each symbol has a name, -and each defined symbol has an address, among other information. If -you compile a C or C++ program into an object file, you will get a -defined symbol for every defined function and global or static -variable. Every undefined function or global variable which is -referenced in the input file will become an undefined symbol. +and each defined symbol has an address, among other information. If you +compile a C or C++ program into an object file, you will get a defined +symbol for every defined function and global or static variable. Every +undefined function or global variable which is referenced in the input +file will become an undefined symbol. - You can see the symbols in an object file by using the `nm' program, -or by using the `objdump' program with the `-t' option. + You can see the symbols in an object file by using the 'nm' program, +or by using the 'objdump' program with the '-t' option. File: ld.info, Node: Script Format, Next: Simple Example, Prev: Basic Script Concepts, Up: Scripts @@ -2302,7 +2296,7 @@ in double quotes. There is no way to use a double quote character in a file name. You may include comments in linker scripts just as in C, delimited by -`/*' and `*/'. As in C, comments are syntactically equivalent to +'/*' and '*/'. As in C, comments are syntactically equivalent to whitespace. @@ -2313,16 +2307,15 @@ File: ld.info, Node: Simple Example, Next: Simple Commands, Prev: Script Form Many linker scripts are fairly simple. - The simplest possible linker script has just one command: -`SECTIONS'. You use the `SECTIONS' command to describe the memory -layout of the output file. + The simplest possible linker script has just one command: 'SECTIONS'. +You use the 'SECTIONS' command to describe the memory layout of the +output file. - The `SECTIONS' command is a powerful command. Here we will describe + The 'SECTIONS' command is a powerful command. Here we will describe a simple use of it. Let's assume your program consists only of code, -initialized data, and uninitialized data. These will be in the -`.text', `.data', and `.bss' sections, respectively. Let's assume -further that these are the only sections which appear in your input -files. +initialized data, and uninitialized data. These will be in the '.text', +'.data', and '.bss' sections, respectively. Let's assume further that +these are the only sections which appear in your input files. For this example, let's say that the code should be loaded at address 0x10000, and that the data should start at address 0x8000000. Here is a @@ -2336,42 +2329,42 @@ linker script which will do that: .bss : { *(.bss) } } - You write the `SECTIONS' command as the keyword `SECTIONS', followed + You write the 'SECTIONS' command as the keyword 'SECTIONS', followed by a series of symbol assignments and output section descriptions enclosed in curly braces. - The first line inside the `SECTIONS' command of the above example -sets the value of the special symbol `.', which is the location -counter. If you do not specify the address of an output section in some -other way (other ways are described later), the address is set from the -current value of the location counter. The location counter is then -incremented by the size of the output section. At the start of the -`SECTIONS' command, the location counter has the value `0'. + The first line inside the 'SECTIONS' command of the above example +sets the value of the special symbol '.', which is the location counter. +If you do not specify the address of an output section in some other way +(other ways are described later), the address is set from the current +value of the location counter. The location counter is then incremented +by the size of the output section. At the start of the 'SECTIONS' +command, the location counter has the value '0'. - The second line defines an output section, `.text'. The colon is + The second line defines an output section, '.text'. The colon is required syntax which may be ignored for now. Within the curly braces after the output section name, you list the names of the input sections -which should be placed into this output section. The `*' is a wildcard -which matches any file name. The expression `*(.text)' means all -`.text' input sections in all input files. - - Since the location counter is `0x10000' when the output section -`.text' is defined, the linker will set the address of the `.text' -section in the output file to be `0x10000'. - - The remaining lines define the `.data' and `.bss' sections in the -output file. The linker will place the `.data' output section at -address `0x8000000'. After the linker places the `.data' output -section, the value of the location counter will be `0x8000000' plus the -size of the `.data' output section. The effect is that the linker will -place the `.bss' output section immediately after the `.data' output +which should be placed into this output section. The '*' is a wildcard +which matches any file name. The expression '*(.text)' means all +'.text' input sections in all input files. + + Since the location counter is '0x10000' when the output section +'.text' is defined, the linker will set the address of the '.text' +section in the output file to be '0x10000'. + + The remaining lines define the '.data' and '.bss' sections in the +output file. The linker will place the '.data' output section at +address '0x8000000'. After the linker places the '.data' output +section, the value of the location counter will be '0x8000000' plus the +size of the '.data' output section. The effect is that the linker will +place the '.bss' output section immediately after the '.data' output section in memory. The linker will ensure that each output section has the required alignment, by increasing the location counter if necessary. In this -example, the specified addresses for the `.text' and `.data' sections -will probably satisfy any alignment constraints, but the linker may -have to create a small gap between the `.data' and `.bss' sections. +example, the specified addresses for the '.text' and '.data' sections +will probably satisfy any alignment constraints, but the linker may have +to create a small gap between the '.data' and '.bss' sections. That's it! That's a simple and complete linker script. @@ -2387,7 +2380,6 @@ In this section we describe the simple linker script commands. * Entry Point:: Setting the entry point * File Commands:: Commands dealing with files - * Format Commands:: Commands dealing with object file formats * REGION_ALIAS:: Assign alias names to memory regions @@ -2400,25 +2392,21 @@ File: ld.info, Node: Entry Point, Next: File Commands, Up: Simple Commands ----------------------------- The first instruction to execute in a program is called the "entry -point". You can use the `ENTRY' linker script command to set the entry +point". You can use the 'ENTRY' linker script command to set the entry point. The argument is a symbol name: ENTRY(SYMBOL) There are several ways to set the entry point. The linker will set the entry point by trying each of the following methods in order, and stopping when one of them succeeds: - * the `-e' ENTRY command-line option; - - * the `ENTRY(SYMBOL)' command in a linker script; - - * the value of a target specific symbol, if it is defined; For many - targets this is `start', but PE and BeOS based systems for example + * the '-e' ENTRY command-line option; + * the 'ENTRY(SYMBOL)' command in a linker script; + * the value of a target specific symbol, if it is defined; For many + targets this is 'start', but PE and BeOS based systems for example check a list of possible entry symbols, matching the first one found. - - * the address of the first byte of the `.text' section, if present; - - * The address `0'. + * the address of the first byte of the '.text' section, if present; + * The address '0'. File: ld.info, Node: File Commands, Next: Format Commands, Prev: Entry Point, Up: Simple Commands @@ -2428,85 +2416,85 @@ File: ld.info, Node: File Commands, Next: Format Commands, Prev: Entry Point, Several linker script commands deal with files. -`INCLUDE FILENAME' - Include the linker script FILENAME at this point. The file will - be searched for in the current directory, and in any directory - specified with the `-L' option. You can nest calls to `INCLUDE' - up to 10 levels deep. +'INCLUDE FILENAME' + Include the linker script FILENAME at this point. The file will be + searched for in the current directory, and in any directory + specified with the '-L' option. You can nest calls to 'INCLUDE' up + to 10 levels deep. - You can place `INCLUDE' directives at the top level, in `MEMORY' or - `SECTIONS' commands, or in output section descriptions. + You can place 'INCLUDE' directives at the top level, in 'MEMORY' or + 'SECTIONS' commands, or in output section descriptions. -`INPUT(FILE, FILE, ...)' -`INPUT(FILE FILE ...)' - The `INPUT' command directs the linker to include the named files +'INPUT(FILE, FILE, ...)' +'INPUT(FILE FILE ...)' + The 'INPUT' command directs the linker to include the named files in the link, as though they were named on the command line. - For example, if you always want to include `subr.o' any time you do + For example, if you always want to include 'subr.o' any time you do a link, but you can't be bothered to put it on every link command - line, then you can put `INPUT (subr.o)' in your linker script. + line, then you can put 'INPUT (subr.o)' in your linker script. In fact, if you like, you can list all of your input files in the - linker script, and then invoke the linker with nothing but a `-T' + linker script, and then invoke the linker with nothing but a '-T' option. In case a "sysroot prefix" is configured, and the filename starts - with the `/' character, and the script being processed was located - inside the "sysroot prefix", the filename will be looked for in - the "sysroot prefix". Otherwise, the linker will try to open the - file in the current directory. If it is not found, the linker - will search through the archive library search path. See the - description of `-L' in *note Command Line Options: Options. + with the '/' character, and the script being processed was located + inside the "sysroot prefix", the filename will be looked for in the + "sysroot prefix". Otherwise, the linker will try to open the file + in the current directory. If it is not found, the linker will + search through the archive library search path. See the + description of '-L' in *note Command Line Options: Options. - If you use `INPUT (-lFILE)', `ld' will transform the name to - `libFILE.a', as with the command line argument `-l'. + If you use 'INPUT (-lFILE)', 'ld' will transform the name to + 'libFILE.a', as with the command line argument '-l'. - When you use the `INPUT' command in an implicit linker script, the + When you use the 'INPUT' command in an implicit linker script, the files will be included in the link at the point at which the linker script file is included. This can affect archive searching. -`GROUP(FILE, FILE, ...)' -`GROUP(FILE FILE ...)' - The `GROUP' command is like `INPUT', except that the named files +'GROUP(FILE, FILE, ...)' +'GROUP(FILE FILE ...)' + The 'GROUP' command is like 'INPUT', except that the named files should all be archives, and they are searched repeatedly until no - new undefined references are created. See the description of `-(' + new undefined references are created. See the description of '-(' in *note Command Line Options: Options. -`AS_NEEDED(FILE, FILE, ...)' -`AS_NEEDED(FILE FILE ...)' - This construct can appear only inside of the `INPUT' or `GROUP' +'AS_NEEDED(FILE, FILE, ...)' +'AS_NEEDED(FILE FILE ...)' + This construct can appear only inside of the 'INPUT' or 'GROUP' commands, among other filenames. The files listed will be handled - as if they appear directly in the `INPUT' or `GROUP' commands, - with the exception of ELF shared libraries, that will be added only - when they are actually needed. This construct essentially enables - `--as-needed' option for all the files listed inside of it and - restores previous `--as-needed' resp. `--no-as-needed' setting + as if they appear directly in the 'INPUT' or 'GROUP' commands, with + the exception of ELF shared libraries, that will be added only when + they are actually needed. This construct essentially enables + '--as-needed' option for all the files listed inside of it and + restores previous '--as-needed' resp. '--no-as-needed' setting afterwards. -`OUTPUT(FILENAME)' - The `OUTPUT' command names the output file. Using - `OUTPUT(FILENAME)' in the linker script is exactly like using `-o +'OUTPUT(FILENAME)' + The 'OUTPUT' command names the output file. Using + 'OUTPUT(FILENAME)' in the linker script is exactly like using '-o FILENAME' on the command line (*note Command Line Options: Options.). If both are used, the command line option takes precedence. - You can use the `OUTPUT' command to define a default name for the - output file other than the usual default of `a.out'. + You can use the 'OUTPUT' command to define a default name for the + output file other than the usual default of 'a.out'. -`SEARCH_DIR(PATH)' - The `SEARCH_DIR' command adds PATH to the list of paths where `ld' - looks for archive libraries. Using `SEARCH_DIR(PATH)' is exactly - like using `-L PATH' on the command line (*note Command Line +'SEARCH_DIR(PATH)' + The 'SEARCH_DIR' command adds PATH to the list of paths where 'ld' + looks for archive libraries. Using 'SEARCH_DIR(PATH)' is exactly + like using '-L PATH' on the command line (*note Command Line Options: Options.). If both are used, then the linker will search both paths. Paths specified using the command line option are searched first. -`STARTUP(FILENAME)' - The `STARTUP' command is just like the `INPUT' command, except - that FILENAME will become the first input file to be linked, as - though it were specified first on the command line. This may be - useful when using a system in which the entry point is always the - start of the first file. +'STARTUP(FILENAME)' + The 'STARTUP' command is just like the 'INPUT' command, except that + FILENAME will become the first input file to be linked, as though + it were specified first on the command line. This may be useful + when using a system in which the entry point is always the start of + the first file. File: ld.info, Node: Format Commands, Next: REGION_ALIAS, Prev: File Commands, Up: Simple Commands @@ -2516,38 +2504,38 @@ File: ld.info, Node: Format Commands, Next: REGION_ALIAS, Prev: File Commands A couple of linker script commands deal with object file formats. -`OUTPUT_FORMAT(BFDNAME)' -`OUTPUT_FORMAT(DEFAULT, BIG, LITTLE)' - The `OUTPUT_FORMAT' command names the BFD format to use for the - output file (*note BFD::). Using `OUTPUT_FORMAT(BFDNAME)' is - exactly like using `--oformat BFDNAME' on the command line (*note +'OUTPUT_FORMAT(BFDNAME)' +'OUTPUT_FORMAT(DEFAULT, BIG, LITTLE)' + The 'OUTPUT_FORMAT' command names the BFD format to use for the + output file (*note BFD::). Using 'OUTPUT_FORMAT(BFDNAME)' is + exactly like using '--oformat BFDNAME' on the command line (*note Command Line Options: Options.). If both are used, the command line option takes precedence. - You can use `OUTPUT_FORMAT' with three arguments to use different - formats based on the `-EB' and `-EL' command line options. This + You can use 'OUTPUT_FORMAT' with three arguments to use different + formats based on the '-EB' and '-EL' command line options. This permits the linker script to set the output format based on the desired endianness. - If neither `-EB' nor `-EL' are used, then the output format will - be the first argument, DEFAULT. If `-EB' is used, the output - format will be the second argument, BIG. If `-EL' is used, the - output format will be the third argument, LITTLE. + If neither '-EB' nor '-EL' are used, then the output format will be + the first argument, DEFAULT. If '-EB' is used, the output format + will be the second argument, BIG. If '-EL' is used, the output + format will be the third argument, LITTLE. - For example, the default linker script for the MIPS ELF target - uses this command: + For example, the default linker script for the MIPS ELF target uses + this command: OUTPUT_FORMAT(elf32-bigmips, elf32-bigmips, elf32-littlemips) This says that the default format for the output file is - `elf32-bigmips', but if the user uses the `-EL' command line - option, the output file will be created in the `elf32-littlemips' + 'elf32-bigmips', but if the user uses the '-EL' command line + option, the output file will be created in the 'elf32-littlemips' format. -`TARGET(BFDNAME)' - The `TARGET' command names the BFD format to use when reading input - files. It affects subsequent `INPUT' and `GROUP' commands. This - command is like using `-b BFDNAME' on the command line (*note - Command Line Options: Options.). If the `TARGET' command is used - but `OUTPUT_FORMAT' is not, then the last `TARGET' command is also +'TARGET(BFDNAME)' + The 'TARGET' command names the BFD format to use when reading input + files. It affects subsequent 'INPUT' and 'GROUP' commands. This + command is like using '-b BFDNAME' on the command line (*note + Command Line Options: Options.). If the 'TARGET' command is used + but 'OUTPUT_FORMAT' is not, then the last 'TARGET' command is also used to set the format for the output file. *Note BFD::. @@ -2562,43 +2550,40 @@ region. REGION_ALIAS(ALIAS, REGION) - The `REGION_ALIAS' function creates an alias name ALIAS for the + The 'REGION_ALIAS' function creates an alias name ALIAS for the memory region REGION. This allows a flexible mapping of output sections to memory regions. An example follows. Suppose we have an application for embedded systems which come with various memory storage devices. All have a general purpose, volatile -memory `RAM' that allows code execution or data storage. Some may have -a read-only, non-volatile memory `ROM' that allows code execution and +memory 'RAM' that allows code execution or data storage. Some may have +a read-only, non-volatile memory 'ROM' that allows code execution and read-only data access. The last variant is a read-only, non-volatile -memory `ROM2' with read-only data access and no code execution +memory 'ROM2' with read-only data access and no code execution capability. We have four output sections: - * `.text' program code; - - * `.rodata' read-only data; - - * `.data' read-write initialized data; - - * `.bss' read-write zero initialized data. + * '.text' program code; + * '.rodata' read-only data; + * '.data' read-write initialized data; + * '.bss' read-write zero initialized data. The goal is to provide a linker command file that contains a system independent part defining the output sections and a system dependent part mapping the output sections to the memory regions available on the system. Our embedded systems come with three different memory setups -`A', `B' and `C': +'A', 'B' and 'C': Section Variant A Variant B Variant C .text RAM ROM ROM .rodata RAM ROM ROM2 .data RAM RAM/ROM RAM/ROM2 .bss RAM RAM RAM - The notation `RAM/ROM' or `RAM/ROM2' means that this section is -loaded into region `ROM' or `ROM2' respectively. Please note that the -load address of the `.data' section starts in all three variants at the -end of the `.rodata' section. + The notation 'RAM/ROM' or 'RAM/ROM2' means that this section is +loaded into region 'ROM' or 'ROM2' respectively. Please note that the +load address of the '.data' section starts in all three variants at the +end of the '.rodata' section. The base linker script that deals with the output sections follows. -It includes the system dependent `linkcmds.memory' file that describes +It includes the system dependent 'linkcmds.memory' file that describes the memory layout: INCLUDE linkcmds.memory @@ -2626,11 +2611,11 @@ the memory layout: } > REGION_BSS } - Now we need three different `linkcmds.memory' files to define memory -regions and alias names. The content of `linkcmds.memory' for the three -variants `A', `B' and `C': -`A' - Here everything goes into the `RAM'. + Now we need three different 'linkcmds.memory' files to define memory +regions and alias names. The content of 'linkcmds.memory' for the three +variants 'A', 'B' and 'C': +'A' + Here everything goes into the 'RAM'. MEMORY { RAM : ORIGIN = 0, LENGTH = 4M @@ -2640,12 +2625,11 @@ variants `A', `B' and `C': REGION_ALIAS("REGION_RODATA", RAM); REGION_ALIAS("REGION_DATA", RAM); REGION_ALIAS("REGION_BSS", RAM); - -`B' - Program code and read-only data go into the `ROM'. Read-write - data goes into the `RAM'. An image of the initialized data is - loaded into the `ROM' and will be copied during system start into - the `RAM'. +'B' + Program code and read-only data go into the 'ROM'. Read-write data + goes into the 'RAM'. An image of the initialized data is loaded + into the 'ROM' and will be copied during system start into the + 'RAM'. MEMORY { ROM : ORIGIN = 0, LENGTH = 3M @@ -2656,12 +2640,11 @@ variants `A', `B' and `C': REGION_ALIAS("REGION_RODATA", ROM); REGION_ALIAS("REGION_DATA", RAM); REGION_ALIAS("REGION_BSS", RAM); - -`C' - Program code goes into the `ROM'. Read-only data goes into the - `ROM2'. Read-write data goes into the `RAM'. An image of the - initialized data is loaded into the `ROM2' and will be copied - during system start into the `RAM'. +'C' + Program code goes into the 'ROM'. Read-only data goes into the + 'ROM2'. Read-write data goes into the 'RAM'. An image of the + initialized data is loaded into the 'ROM2' and will be copied + during system start into the 'RAM'. MEMORY { ROM : ORIGIN = 0, LENGTH = 2M @@ -2675,7 +2658,7 @@ variants `A', `B' and `C': REGION_ALIAS("REGION_BSS", RAM); It is possible to write a common system initialization routine to -copy the `.data' section from `ROM' or `ROM2' into the `RAM' if +copy the '.data' section from 'ROM' or 'ROM2' into the 'RAM' if necessary: #include <string.h> @@ -2699,42 +2682,42 @@ File: ld.info, Node: Miscellaneous Commands, Prev: REGION_ALIAS, Up: Simple C There are a few other linker scripts commands. -`ASSERT(EXP, MESSAGE)' +'ASSERT(EXP, MESSAGE)' Ensure that EXP is non-zero. If it is zero, then exit the linker with an error code, and print MESSAGE. -`EXTERN(SYMBOL SYMBOL ...)' +'EXTERN(SYMBOL SYMBOL ...)' Force SYMBOL to be entered in the output file as an undefined symbol. Doing this may, for example, trigger linking of additional modules from standard libraries. You may list several SYMBOLs for - each `EXTERN', and you may use `EXTERN' multiple times. This - command has the same effect as the `-u' command-line option. + each 'EXTERN', and you may use 'EXTERN' multiple times. This + command has the same effect as the '-u' command-line option. -`FORCE_COMMON_ALLOCATION' - This command has the same effect as the `-d' command-line option: - to make `ld' assign space to common symbols even if a relocatable - output file is specified (`-r'). +'FORCE_COMMON_ALLOCATION' + This command has the same effect as the '-d' command-line option: + to make 'ld' assign space to common symbols even if a relocatable + output file is specified ('-r'). -`INHIBIT_COMMON_ALLOCATION' - This command has the same effect as the `--no-define-common' - command-line option: to make `ld' omit the assignment of addresses +'INHIBIT_COMMON_ALLOCATION' + This command has the same effect as the '--no-define-common' + command-line option: to make 'ld' omit the assignment of addresses to common symbols even for a non-relocatable output file. -`INSERT [ AFTER | BEFORE ] OUTPUT_SECTION' - This command is typically used in a script specified by `-T' to - augment the default `SECTIONS' with, for example, overlays. It +'INSERT [ AFTER | BEFORE ] OUTPUT_SECTION' + This command is typically used in a script specified by '-T' to + augment the default 'SECTIONS' with, for example, overlays. It inserts all prior linker script statements after (or before) - OUTPUT_SECTION, and also causes `-T' to not override the default + OUTPUT_SECTION, and also causes '-T' to not override the default linker script. The exact insertion point is as for orphan sections. *Note Location Counter::. The insertion happens after the linker has mapped input sections to output sections. Prior to - the insertion, since `-T' scripts are parsed before the default - linker script, statements in the `-T' script occur before the + the insertion, since '-T' scripts are parsed before the default + linker script, statements in the '-T' script occur before the default linker script statements in the internal linker representation of the script. In particular, input section - assignments will be made to `-T' output sections before those in - the default script. Here is an example of how a `-T' script using - `INSERT' might look: + assignments will be made to '-T' output sections before those in + the default script. Here is an example of how a '-T' script using + 'INSERT' might look: SECTIONS { @@ -2746,8 +2729,8 @@ There are a few other linker scripts commands. } INSERT AFTER .text; -`NOCROSSREFS(SECTION SECTION ...)' - This command may be used to tell `ld' to issue an error about any +'NOCROSSREFS(SECTION SECTION ...)' + This command may be used to tell 'ld' to issue an error about any references among certain output sections. In certain types of programs, particularly on embedded systems when @@ -2756,21 +2739,21 @@ There are a few other linker scripts commands. sections would be errors. For example, it would be an error if code in one section called a function defined in the other section. - The `NOCROSSREFS' command takes a list of output section names. If - `ld' detects any cross references between the sections, it reports + The 'NOCROSSREFS' command takes a list of output section names. If + 'ld' detects any cross references between the sections, it reports an error and returns a non-zero exit status. Note that the - `NOCROSSREFS' command uses output section names, not input section + 'NOCROSSREFS' command uses output section names, not input section names. -`OUTPUT_ARCH(BFDARCH)' +'OUTPUT_ARCH(BFDARCH)' Specify a particular output machine architecture. The argument is one of the names used by the BFD library (*note BFD::). You can - see the architecture of an object file by using the `objdump' - program with the `-f' option. + see the architecture of an object file by using the 'objdump' + program with the '-f' option. -`LD_FEATURE(STRING)' - This command may be used to modify `ld' behavior. If STRING is - `"SANE_EXPR"' then absolute symbols and numbers in a script are +'LD_FEATURE(STRING)' + This command may be used to modify 'ld' behavior. If STRING is + '"SANE_EXPR"' then absolute symbols and numbers in a script are simply treated as numbers everywhere. *Note Expression Section::. @@ -2798,30 +2781,30 @@ File: ld.info, Node: Simple Assignments, Next: HIDDEN, Up: Assignments You may assign to a symbol using any of the C assignment operators: -`SYMBOL = EXPRESSION ;' -`SYMBOL += EXPRESSION ;' -`SYMBOL -= EXPRESSION ;' -`SYMBOL *= EXPRESSION ;' -`SYMBOL /= EXPRESSION ;' -`SYMBOL <<= EXPRESSION ;' -`SYMBOL >>= EXPRESSION ;' -`SYMBOL &= EXPRESSION ;' -`SYMBOL |= EXPRESSION ;' - - The first case will define SYMBOL to the value of EXPRESSION. In -the other cases, SYMBOL must already be defined, and the value will be +'SYMBOL = EXPRESSION ;' +'SYMBOL += EXPRESSION ;' +'SYMBOL -= EXPRESSION ;' +'SYMBOL *= EXPRESSION ;' +'SYMBOL /= EXPRESSION ;' +'SYMBOL <<= EXPRESSION ;' +'SYMBOL >>= EXPRESSION ;' +'SYMBOL &= EXPRESSION ;' +'SYMBOL |= EXPRESSION ;' + + The first case will define SYMBOL to the value of EXPRESSION. In the +other cases, SYMBOL must already be defined, and the value will be adjusted accordingly. - The special symbol name `.' indicates the location counter. You may -only use this within a `SECTIONS' command. *Note Location Counter::. + The special symbol name '.' indicates the location counter. You may +only use this within a 'SECTIONS' command. *Note Location Counter::. The semicolon after EXPRESSION is required. Expressions are defined below; see *note Expressions::. You may write symbol assignments as commands in their own right, or -as statements within a `SECTIONS' command, or as part of an output -section description in a `SECTIONS' command. +as statements within a 'SECTIONS' command, or as part of an output +section description in a 'SECTIONS' command. The section of the symbol will be set from the section of the expression; for more information, see *note Expression Section::. @@ -2840,10 +2823,10 @@ assignments may be used: _bdata = (. + 3) & ~ 3; .data : { *(.data) } } - In this example, the symbol `floating_point' will be defined as -zero. The symbol `_etext' will be defined as the address following the -last `.text' input section. The symbol `_bdata' will be defined as the -address following the `.text' output section aligned upward to a 4 byte +In this example, the symbol 'floating_point' will be defined as zero. +The symbol '_etext' will be defined as the address following the last +'.text' input section. The symbol '_bdata' will be defined as the +address following the '.text' output section aligned upward to a 4 byte boundary. @@ -2853,10 +2836,10 @@ File: ld.info, Node: HIDDEN, Next: PROVIDE, Prev: Simple Assignments, Up: As ------------ For ELF targeted ports, define a symbol that will be hidden and won't be -exported. The syntax is `HIDDEN(SYMBOL = EXPRESSION)'. +exported. The syntax is 'HIDDEN(SYMBOL = EXPRESSION)'. Here is the example from *note Simple Assignments::, rewritten to use -`HIDDEN': +'HIDDEN': HIDDEN(floating_point = 0); SECTIONS @@ -2869,7 +2852,7 @@ exported. The syntax is `HIDDEN(SYMBOL = EXPRESSION)'. HIDDEN(_bdata = (. + 3) & ~ 3); .data : { *(.data) } } - In this case none of the three symbols will be visible outside this +In this case none of the three symbols will be visible outside this module. @@ -2880,13 +2863,13 @@ File: ld.info, Node: PROVIDE, Next: PROVIDE_HIDDEN, Prev: HIDDEN, Up: Assign In some cases, it is desirable for a linker script to define a symbol only if it is referenced and is not defined by any object included in -the link. For example, traditional linkers defined the symbol `etext'. -However, ANSI C requires that the user be able to use `etext' as a -function name without encountering an error. The `PROVIDE' keyword may -be used to define a symbol, such as `etext', only if it is referenced -but not defined. The syntax is `PROVIDE(SYMBOL = EXPRESSION)'. +the link. For example, traditional linkers defined the symbol 'etext'. +However, ANSI C requires that the user be able to use 'etext' as a +function name without encountering an error. The 'PROVIDE' keyword may +be used to define a symbol, such as 'etext', only if it is referenced +but not defined. The syntax is 'PROVIDE(SYMBOL = EXPRESSION)'. - Here is an example of using `PROVIDE' to define `etext': + Here is an example of using 'PROVIDE' to define 'etext': SECTIONS { .text : @@ -2897,11 +2880,11 @@ but not defined. The syntax is `PROVIDE(SYMBOL = EXPRESSION)'. } } - In this example, if the program defines `_etext' (with a leading + In this example, if the program defines '_etext' (with a leading underscore), the linker will give a multiple definition error. If, on -the other hand, the program defines `etext' (with no leading +the other hand, the program defines 'etext' (with no leading underscore), the linker will silently use the definition in the program. -If the program references `etext' but does not define it, the linker +If the program references 'etext' but does not define it, the linker will use the definition in the linker script. @@ -2910,8 +2893,8 @@ File: ld.info, Node: PROVIDE_HIDDEN, Next: Source Code Reference, Prev: PROVI 3.5.4 PROVIDE_HIDDEN -------------------- -Similar to `PROVIDE'. For ELF targeted ports, the symbol will be -hidden and won't be exported. +Similar to 'PROVIDE'. For ELF targeted ports, the symbol will be hidden +and won't be exported. File: ld.info, Node: Source Code Reference, Prev: PROVIDE_HIDDEN, Up: Assignments @@ -2927,11 +2910,11 @@ that does not have a value. Before going further, it is important to note that compilers often transform names in the source code into different names when they are stored in the symbol table. For example, Fortran compilers commonly -prepend or append an underscore, and C++ performs extensive `name -mangling'. Therefore there might be a discrepancy between the name of -a variable as it is used in source code and the name of the same -variable as it is defined in a linker script. For example in C a -linker script variable might be referred to as: +prepend or append an underscore, and C++ performs extensive 'name +mangling'. Therefore there might be a discrepancy between the name of a +variable as it is used in source code and the name of the same variable +as it is defined in a linker script. For example in C a linker script +variable might be referred to as: extern int foo; @@ -2952,8 +2935,8 @@ following C declaration, at file scope: int foo = 1000; - creates a entry called `foo' in the symbol table. This entry holds -the address of an `int' sized block of memory where the number 1000 is + creates an entry called 'foo' in the symbol table. This entry holds +the address of an 'int' sized block of memory where the number 1000 is initially stored. When a program references a symbol the compiler generates code that @@ -2963,34 +2946,33 @@ So: foo = 1; - looks up the symbol `foo' in the symbol table, gets the address + looks up the symbol 'foo' in the symbol table, gets the address associated with this symbol and then writes the value 1 into that address. Whereas: int * a = & foo; - looks up the symbol `foo' in the symbol table, gets it address and + looks up the symbol 'foo' in the symbol table, gets its address and then copies this address into the block of memory associated with the -variable `a'. +variable 'a'. Linker scripts symbol declarations, by contrast, create an entry in -the symbol table but do not assign any memory to them. Thus they are -an address without a value. So for example the linker script -definition: +the symbol table but do not assign any memory to them. Thus they are an +address without a value. So for example the linker script definition: foo = 1000; - creates an entry in the symbol table called `foo' which holds the + creates an entry in the symbol table called 'foo' which holds the address of memory location 1000, but nothing special is stored at -address 1000. This means that you cannot access the _value_ of a -linker script defined symbol - it has no value - all you can do is -access the _address_ of a linker script defined symbol. +address 1000. This means that you cannot access the _value_ of a linker +script defined symbol - it has no value - all you can do is access the +_address_ of a linker script defined symbol. Hence when you are using a linker script defined symbol in source -code you should always take the address of the symbol, and never -attempt to use its value. For example suppose you want to copy the -contents of a section of memory called .ROM into a section called -.FLASH and the linker script contains these declarations: +code you should always take the address of the symbol, and never attempt +to use its value. For example suppose you want to copy the contents of +a section of memory called .ROM into a section called .FLASH and the +linker script contains these declarations: start_of_ROM = .ROM; end_of_ROM = .ROM + sizeof (.ROM) - 1; @@ -3002,7 +2984,7 @@ contents of a section of memory called .ROM into a section called memcpy (& start_of_FLASH, & start_of_ROM, & end_of_ROM - & start_of_ROM); - Note the use of the `&' operators. These are correct. + Note the use of the '&' operators. These are correct. File: ld.info, Node: SECTIONS, Next: MEMORY, Prev: Assignments, Up: Scripts @@ -3010,10 +2992,10 @@ File: ld.info, Node: SECTIONS, Next: MEMORY, Prev: Assignments, Up: Scripts 3.6 SECTIONS Command ==================== -The `SECTIONS' command tells the linker how to map input sections into +The 'SECTIONS' command tells the linker how to map input sections into output sections, and how to place the output sections in memory. - The format of the `SECTIONS' command is: + The format of the 'SECTIONS' command is: SECTIONS { SECTIONS-COMMAND @@ -3023,16 +3005,13 @@ output sections, and how to place the output sections in memory. Each SECTIONS-COMMAND may of be one of the following: - * an `ENTRY' command (*note Entry command: Entry Point.) - + * an 'ENTRY' command (*note Entry command: Entry Point.) * a symbol assignment (*note Assignments::) - * an output section description - * an overlay description - The `ENTRY' command and symbol assignments are permitted inside the -`SECTIONS' command for convenience in using the location counter in + The 'ENTRY' command and symbol assignments are permitted inside the +'SECTIONS' command for convenience in using the location counter in those commands. This can also make the linker script easier to understand because you can use those commands at meaningful points in the layout of the output file. @@ -3040,7 +3019,7 @@ the layout of the output file. Output section descriptions and overlay descriptions are described below. - If you do not use a `SECTIONS' command in your linker script, the + If you do not use a 'SECTIONS' command in your linker script, the linker will place each input section into an identically named output section in the order that the sections are first encountered in the input files. If all input sections are present in the first file, for @@ -3068,7 +3047,7 @@ File: ld.info, Node: Output Section Description, Next: Output Section Name, U The full description of an output section looks like this: SECTION [ADDRESS] [(TYPE)] : [AT(LMA)] - [ALIGN(SECTION_ALIGN)] + [ALIGN(SECTION_ALIGN) | ALIGN_WITH_INPUT] [SUBALIGN(SUBSECTION_ALIGN)] [CONSTRAINT] { @@ -3087,11 +3066,8 @@ line breaks and other white space are optional. Each OUTPUT-SECTION-COMMAND may be one of the following: * a symbol assignment (*note Assignments::) - * an input section description (*note Input Section::) - * data values to include directly (*note Output Section Data::) - * a special output section keyword (*note Output Section Keywords::) @@ -3102,15 +3078,15 @@ File: ld.info, Node: Output Section Name, Next: Output Section Address, Prev: The name of the output section is SECTION. SECTION must meet the constraints of your output format. In formats which only support a -limited number of sections, such as `a.out', the name must be one of -the names supported by the format (`a.out', for example, allows only -`.text', `.data' or `.bss'). If the output format supports any number +limited number of sections, such as 'a.out', the name must be one of the +names supported by the format ('a.out', for example, allows only +'.text', '.data' or '.bss'). If the output format supports any number of sections, but with numbers and not names (as is the case for Oasys), the name should be supplied as a quoted numeric string. A section name -may consist of any sequence of characters, but a name which contains -any unusual characters such as commas must be quoted. +may consist of any sequence of characters, but a name which contains any +unusual characters such as commas must be quoted. - The output section name `/DISCARD/' is special; *note Output Section + The output section name '/DISCARD/' is special; *note Output Section Discarding::. @@ -3119,8 +3095,8 @@ File: ld.info, Node: Output Section Address, Next: Input Section, Prev: Outpu 3.6.3 Output Section Address ---------------------------- -The ADDRESS is an expression for the VMA (the virtual memory address) -of the output section. This address is optional, but if it is provided +The ADDRESS is an expression for the VMA (the virtual memory address) of +the output section. This address is optional, but if it is provided then the output address will be set exactly as specified. If the output address is not specified then one will be chosen for @@ -3153,18 +3129,18 @@ and .text : { *(.text) } -are subtly different. The first will set the address of the `.text' -output section to the current value of the location counter. The -second will set it to the current value of the location counter aligned -to the strictest alignment of any of the `.text' input sections. +are subtly different. The first will set the address of the '.text' +output section to the current value of the location counter. The second +will set it to the current value of the location counter aligned to the +strictest alignment of any of the '.text' input sections. - The ADDRESS may be an arbitrary expression; *note Expressions::. -For example, if you want to align the section on a 0x10 byte boundary, -so that the lowest four bits of the section address are zero, you could -do something like this: + The ADDRESS may be an arbitrary expression; *note Expressions::. For +example, if you want to align the section on a 0x10 byte boundary, so +that the lowest four bits of the section address are zero, you could do +something like this: .text ALIGN(0x10) : { *(.text) } - This works because `ALIGN' returns the current location counter -aligned upward to the specified value. +This works because 'ALIGN' returns the current location counter aligned +upward to the specified value. Specifying ADDRESS for a section will change the value of the location counter, provided that the section is non-empty. (Empty @@ -3205,25 +3181,24 @@ describe further below (*note Input Section Wildcards::). The most common input section description is to include all input sections with a particular name in the output section. For example, to -include all input `.text' sections, you would write: +include all input '.text' sections, you would write: *(.text) - Here the `*' is a wildcard which matches any file name. To exclude -a list of files from matching the file name wildcard, EXCLUDE_FILE may -be used to match all files except the ones specified in the -EXCLUDE_FILE list. For example: +Here the '*' is a wildcard which matches any file name. To exclude a +list of files from matching the file name wildcard, EXCLUDE_FILE may be +used to match all files except the ones specified in the EXCLUDE_FILE +list. For example: *(EXCLUDE_FILE (*crtend.o *otherfile.o) .ctors) - will cause all .ctors sections from all files except `crtend.o' and -`otherfile.o' to be included. + will cause all .ctors sections from all files except 'crtend.o' and +'otherfile.o' to be included. There are two ways to include more than one section: *(.text .rdata) *(.text) *(.rdata) - The difference between these is the order in which the `.text' and -`.rdata' input sections will appear in the output section. In the -first example, they will be intermingled, appearing in the same order as -they are found in the linker input. In the second example, all `.text' -input sections will appear first, followed by all `.rdata' input -sections. +The difference between these is the order in which the '.text' and +'.rdata' input sections will appear in the output section. In the first +example, they will be intermingled, appearing in the same order as they +are found in the linker input. In the second example, all '.text' input +sections will appear first, followed by all '.rdata' input sections. You can specify a file name to include sections from a particular file. You would do this if one or more of your files contain special @@ -3241,46 +3216,44 @@ sections: .text2 : { INPUT_SECTION_FLAGS (!SHF_WRITE) *(.text) } } - In this example, the output section `.text' will be comprised of any + In this example, the output section '.text' will be comprised of any input section matching the name *(.text) whose section header flags -`SHF_MERGE' and `SHF_STRINGS' are set. The output section `.text2' -will be comprised of any input section matching the name *(.text) whose -section header flag `SHF_WRITE' is clear. +'SHF_MERGE' and 'SHF_STRINGS' are set. The output section '.text2' will +be comprised of any input section matching the name *(.text) whose +section header flag 'SHF_WRITE' is clear. You can also specify files within archives by writing a pattern matching the archive, a colon, then the pattern matching the file, with no whitespace around the colon. -`archive:file' +'archive:file' matches file within archive - -`archive:' +'archive:' matches the whole archive - -`:file' +':file' matches file but not one in an archive - Either one or both of `archive' and `file' can contain shell + Either one or both of 'archive' and 'file' can contain shell wildcards. On DOS based file systems, the linker will assume that a -single letter followed by a colon is a drive specifier, so `c:myfile.o' -is a simple file specification, not `myfile.o' within an archive called -`c'. `archive:file' filespecs may also be used within an -`EXCLUDE_FILE' list, but may not appear in other linker script -contexts. For instance, you cannot extract a file from an archive by -using `archive:file' in an `INPUT' command. +single letter followed by a colon is a drive specifier, so 'c:myfile.o' +is a simple file specification, not 'myfile.o' within an archive called +'c'. 'archive:file' filespecs may also be used within an 'EXCLUDE_FILE' +list, but may not appear in other linker script contexts. For instance, +you cannot extract a file from an archive by using 'archive:file' in an +'INPUT' command. If you use a file name without a list of sections, then all sections in the input file will be included in the output section. This is not commonly done, but it may by useful on occasion. For example: data.o - When you use a file name which is not an `archive:file' specifier -and does not contain any wild card characters, the linker will first -see if you also specified the file name on the linker command line or -in an `INPUT' command. If you did not, the linker will attempt to open -the file as an input file, as though it appeared on the command line. -Note that this differs from an `INPUT' command, because the linker will -not search for the file in the archive search path. + When you use a file name which is not an 'archive:file' specifier and +does not contain any wild card characters, the linker will first see if +you also specified the file name on the linker command line or in an +'INPUT' command. If you did not, the linker will attempt to open the +file as an input file, as though it appeared on the command line. Note +that this differs from an 'INPUT' command, because the linker will not +search for the file in the archive search path. File: ld.info, Node: Input Section Wildcards, Next: Input Section Common, Prev: Input Section Basics, Up: Input Section @@ -3291,80 +3264,75 @@ File: ld.info, Node: Input Section Wildcards, Next: Input Section Common, Pre In an input section description, either the file name or the section name or both may be wildcard patterns. - The file name of `*' seen in many examples is a simple wildcard + The file name of '*' seen in many examples is a simple wildcard pattern for the file name. The wildcard patterns are like those used by the Unix shell. -`*' +'*' matches any number of characters - -`?' +'?' matches any single character - -`[CHARS]' - matches a single instance of any of the CHARS; the `-' character - may be used to specify a range of characters, as in `[a-z]' to +'[CHARS]' + matches a single instance of any of the CHARS; the '-' character + may be used to specify a range of characters, as in '[a-z]' to match any lower case letter - -`\' +'\' quotes the following character When a file name is matched with a wildcard, the wildcard characters -will not match a `/' character (used to separate directory names on -Unix). A pattern consisting of a single `*' character is an exception; -it will always match any file name, whether it contains a `/' or not. -In a section name, the wildcard characters will match a `/' character. +will not match a '/' character (used to separate directory names on +Unix). A pattern consisting of a single '*' character is an exception; +it will always match any file name, whether it contains a '/' or not. +In a section name, the wildcard characters will match a '/' character. File name wildcard patterns only match files which are explicitly -specified on the command line or in an `INPUT' command. The linker -does not search directories to expand wildcards. +specified on the command line or in an 'INPUT' command. The linker does +not search directories to expand wildcards. If a file name matches more than one wildcard pattern, or if a file name appears explicitly and is also matched by a wildcard pattern, the linker will use the first match in the linker script. For example, this sequence of input section descriptions is probably in error, because the -`data.o' rule will not be used: +'data.o' rule will not be used: .data : { *(.data) } .data1 : { data.o(.data) } Normally, the linker will place files and sections matched by wildcards in the order in which they are seen during the link. You can -change this by using the `SORT_BY_NAME' keyword, which appears before a -wildcard pattern in parentheses (e.g., `SORT_BY_NAME(.text*)'). When -the `SORT_BY_NAME' keyword is used, the linker will sort the files or +change this by using the 'SORT_BY_NAME' keyword, which appears before a +wildcard pattern in parentheses (e.g., 'SORT_BY_NAME(.text*)'). When +the 'SORT_BY_NAME' keyword is used, the linker will sort the files or sections into ascending order by name before placing them in the output file. - `SORT_BY_ALIGNMENT' is very similar to `SORT_BY_NAME'. The -difference is `SORT_BY_ALIGNMENT' will sort sections into ascending -order by alignment before placing them in the output file. + 'SORT_BY_ALIGNMENT' is very similar to 'SORT_BY_NAME'. The +difference is 'SORT_BY_ALIGNMENT' will sort sections into descending +order by alignment before placing them in the output file. Larger +alignments are placed before smaller alignments in order to reduce the +amount of padding necessary. - `SORT_BY_INIT_PRIORITY' is very similar to `SORT_BY_NAME'. The -difference is `SORT_BY_INIT_PRIORITY' will sort sections into ascending + 'SORT_BY_INIT_PRIORITY' is very similar to 'SORT_BY_NAME'. The +difference is 'SORT_BY_INIT_PRIORITY' will sort sections into ascending order by numerical value of the GCC init_priority attribute encoded in the section name before placing them in the output file. - `SORT' is an alias for `SORT_BY_NAME'. + 'SORT' is an alias for 'SORT_BY_NAME'. When there are nested section sorting commands in linker script, there can be at most 1 level of nesting for section sorting commands. - 1. `SORT_BY_NAME' (`SORT_BY_ALIGNMENT' (wildcard section pattern)). - It will sort the input sections by name first, then by alignment - if 2 sections have the same name. - - 2. `SORT_BY_ALIGNMENT' (`SORT_BY_NAME' (wildcard section pattern)). - It will sort the input sections by alignment first, then by name - if 2 sections have the same alignment. - - 3. `SORT_BY_NAME' (`SORT_BY_NAME' (wildcard section pattern)) is - treated the same as `SORT_BY_NAME' (wildcard section pattern). - - 4. `SORT_BY_ALIGNMENT' (`SORT_BY_ALIGNMENT' (wildcard section - pattern)) is treated the same as `SORT_BY_ALIGNMENT' (wildcard + 1. 'SORT_BY_NAME' ('SORT_BY_ALIGNMENT' (wildcard section pattern)). + It will sort the input sections by name first, then by alignment if + two sections have the same name. + 2. 'SORT_BY_ALIGNMENT' ('SORT_BY_NAME' (wildcard section pattern)). + It will sort the input sections by alignment first, then by name if + two sections have the same alignment. + 3. 'SORT_BY_NAME' ('SORT_BY_NAME' (wildcard section pattern)) is + treated the same as 'SORT_BY_NAME' (wildcard section pattern). + 4. 'SORT_BY_ALIGNMENT' ('SORT_BY_ALIGNMENT' (wildcard section + pattern)) is treated the same as 'SORT_BY_ALIGNMENT' (wildcard section pattern). - 5. All other nested section sorting commands are invalid. When both command line section sorting option and linker script @@ -3375,30 +3343,29 @@ precedence over the command line option. command line option will make the section sorting command to be treated as nested sorting command. - 1. `SORT_BY_NAME' (wildcard section pattern ) with `--sort-sections - alignment' is equivalent to `SORT_BY_NAME' (`SORT_BY_ALIGNMENT' + 1. 'SORT_BY_NAME' (wildcard section pattern ) with '--sort-sections + alignment' is equivalent to 'SORT_BY_NAME' ('SORT_BY_ALIGNMENT' + (wildcard section pattern)). + 2. 'SORT_BY_ALIGNMENT' (wildcard section pattern) with '--sort-section + name' is equivalent to 'SORT_BY_ALIGNMENT' ('SORT_BY_NAME' (wildcard section pattern)). - - 2. `SORT_BY_ALIGNMENT' (wildcard section pattern) with - `--sort-section name' is equivalent to `SORT_BY_ALIGNMENT' - (`SORT_BY_NAME' (wildcard section pattern)). If the section sorting command in linker script is nested, the command line option will be ignored. - `SORT_NONE' disables section sorting by ignoring the command line + 'SORT_NONE' disables section sorting by ignoring the command line section sorting option. If you ever get confused about where input sections are going, use -the `-M' linker option to generate a map file. The map file shows +the '-M' linker option to generate a map file. The map file shows precisely how input sections are mapped to output sections. This example shows how wildcard patterns might be used to partition -files. This linker script directs the linker to place all `.text' -sections in `.text' and all `.bss' sections in `.bss'. The linker will -place the `.data' section from all files beginning with an upper case -character in `.DATA'; for all other files, the linker will place the -`.data' section in `.data'. +files. This linker script directs the linker to place all '.text' +sections in '.text' and all '.bss' sections in '.bss'. The linker will +place the '.data' section from all files beginning with an upper case +character in '.DATA'; for all other files, the linker will place the +'.data' section in '.data'. SECTIONS { .text : { *(.text) } .DATA : { [A-Z]*(.data) } @@ -3415,28 +3382,28 @@ File: ld.info, Node: Input Section Common, Next: Input Section Keep, Prev: In A special notation is needed for common symbols, because in many object file formats common symbols do not have a particular input section. The linker treats common symbols as though they are in an input section -named `COMMON'. +named 'COMMON'. - You may use file names with the `COMMON' section just as with any + You may use file names with the 'COMMON' section just as with any other input sections. You can use this to place common symbols from a particular input file in one section while common symbols from other input files are placed in another section. In most cases, common symbols in input files will be placed in the -`.bss' section in the output file. For example: +'.bss' section in the output file. For example: .bss { *(.bss) *(COMMON) } Some object file formats have more than one type of common symbol. For example, the MIPS ELF object file format distinguishes standard common symbols and small common symbols. In this case, the linker will use a different special section name for other types of common symbols. -In the case of MIPS ELF, the linker uses `COMMON' for standard common -symbols and `.scommon' for small common symbols. This permits you to +In the case of MIPS ELF, the linker uses 'COMMON' for standard common +symbols and '.scommon' for small common symbols. This permits you to map the different types of common symbols into memory at different locations. - You will sometimes see `[COMMON]' in old linker scripts. This -notation is now considered obsolete. It is equivalent to `*(COMMON)'. + You will sometimes see '[COMMON]' in old linker scripts. This +notation is now considered obsolete. It is equivalent to '*(COMMON)'. File: ld.info, Node: Input Section Keep, Next: Input Section Example, Prev: Input Section Common, Up: Input Section @@ -3444,10 +3411,10 @@ File: ld.info, Node: Input Section Keep, Next: Input Section Example, Prev: I 3.6.4.4 Input Section and Garbage Collection ............................................ -When link-time garbage collection is in use (`--gc-sections'), it is +When link-time garbage collection is in use ('--gc-sections'), it is often useful to mark sections that should not be eliminated. This is accomplished by surrounding an input section's wildcard entry with -`KEEP()', as in `KEEP(*(.init))' or `KEEP(SORT_BY_NAME(*)(.ctors))'. +'KEEP()', as in 'KEEP(*(.init))' or 'KEEP(SORT_BY_NAME(*)(.ctors))'. File: ld.info, Node: Input Section Example, Prev: Input Section Keep, Up: Input Section @@ -3456,13 +3423,13 @@ File: ld.info, Node: Input Section Example, Prev: Input Section Keep, Up: Inp ............................. The following example is a complete linker script. It tells the linker -to read all of the sections from file `all.o' and place them at the -start of output section `outputa' which starts at location `0x10000'. -All of section `.input1' from file `foo.o' follows immediately, in the -same output section. All of section `.input2' from `foo.o' goes into -output section `outputb', followed by section `.input1' from `foo1.o'. -All of the remaining `.input1' and `.input2' sections from any files -are written to output section `outputc'. +to read all of the sections from file 'all.o' and place them at the +start of output section 'outputa' which starts at location '0x10000'. +All of section '.input1' from file 'foo.o' follows immediately, in the +same output section. All of section '.input2' from 'foo.o' goes into +output section 'outputb', followed by section '.input1' from 'foo1.o'. +All of the remaining '.input1' and '.input2' sections from any files are +written to output section 'outputc'. SECTIONS { outputa 0x10000 : @@ -3489,24 +3456,24 @@ File: ld.info, Node: Output Section Data, Next: Output Section Keywords, Prev ------------------------- You can include explicit bytes of data in an output section by using -`BYTE', `SHORT', `LONG', `QUAD', or `SQUAD' as an output section +'BYTE', 'SHORT', 'LONG', 'QUAD', or 'SQUAD' as an output section command. Each keyword is followed by an expression in parentheses providing the value to store (*note Expressions::). The value of the expression is stored at the current value of the location counter. - The `BYTE', `SHORT', `LONG', and `QUAD' commands store one, two, + The 'BYTE', 'SHORT', 'LONG', and 'QUAD' commands store one, two, four, and eight bytes (respectively). After storing the bytes, the location counter is incremented by the number of bytes stored. For example, this will store the byte 1 followed by the four byte -value of the symbol `addr': +value of the symbol 'addr': BYTE(1) LONG(addr) - When using a 64 bit host or target, `QUAD' and `SQUAD' are the same; + When using a 64 bit host or target, 'QUAD' and 'SQUAD' are the same; they both store an 8 byte, or 64 bit, value. When both host and target -are 32 bits, an expression is computed as 32 bits. In this case `QUAD' -stores a 32 bit value zero extended to 64 bits, and `SQUAD' stores a 32 +are 32 bits, an expression is computed as 32 bits. In this case 'QUAD' +stores a 32 bit value zero extended to 64 bits, and 'SQUAD' stores a 32 bit value sign extended to 64 bits. If the object file format of the output file has an explicit @@ -3517,28 +3484,28 @@ stored in the endianness of the first input object file. Note--these commands only work inside a section description and not between them, so the following will produce an error from the linker: - SECTIONS { .text : { *(.text) } LONG(1) .data : { *(.data) } } + SECTIONS { .text : { *(.text) } LONG(1) .data : { *(.data) } } whereas this will work: - SECTIONS { .text : { *(.text) ; LONG(1) } .data : { *(.data) } } + SECTIONS { .text : { *(.text) ; LONG(1) } .data : { *(.data) } } - You may use the `FILL' command to set the fill pattern for the + You may use the 'FILL' command to set the fill pattern for the current section. It is followed by an expression in parentheses. Any otherwise unspecified regions of memory within the section (for example, gaps left due to the required alignment of input sections) are filled -with the value of the expression, repeated as necessary. A `FILL' +with the value of the expression, repeated as necessary. A 'FILL' statement covers memory locations after the point at which it occurs in -the section definition; by including more than one `FILL' statement, -you can have different fill patterns in different parts of an output +the section definition; by including more than one 'FILL' statement, you +can have different fill patterns in different parts of an output section. This example shows how to fill unspecified regions of memory with the -value `0x90': +value '0x90': FILL(0x90909090) - The `FILL' command is similar to the `=FILLEXP' output section + The 'FILL' command is similar to the '=FILLEXP' output section attribute, but it only affects the part of the section following the -`FILL' command, rather than the entire section. If both are used, the -`FILL' command takes precedence. *Note Output Section Fill::, for +'FILL' command, rather than the entire section. If both are used, the +'FILL' command takes precedence. *Note Output Section Fill::, for details on the fill expression. @@ -3550,43 +3517,43 @@ File: ld.info, Node: Output Section Keywords, Next: Output Section Discarding, There are a couple of keywords which can appear as output section commands. -`CREATE_OBJECT_SYMBOLS' +'CREATE_OBJECT_SYMBOLS' The command tells the linker to create a symbol for each input file. The name of each symbol will be the name of the corresponding input file. The section of each symbol will be the - output section in which the `CREATE_OBJECT_SYMBOLS' command + output section in which the 'CREATE_OBJECT_SYMBOLS' command appears. This is conventional for the a.out object file format. It is not normally used for any other object file format. -`CONSTRUCTORS' +'CONSTRUCTORS' When linking using the a.out object file format, the linker uses an unusual set construct to support C++ global constructors and destructors. When linking object file formats which do not support arbitrary sections, such as ECOFF and XCOFF, the linker will automatically recognize C++ global constructors and destructors by - name. For these object file formats, the `CONSTRUCTORS' command + name. For these object file formats, the 'CONSTRUCTORS' command tells the linker to place constructor information in the output - section where the `CONSTRUCTORS' command appears. The - `CONSTRUCTORS' command is ignored for other object file formats. + section where the 'CONSTRUCTORS' command appears. The + 'CONSTRUCTORS' command is ignored for other object file formats. - The symbol `__CTOR_LIST__' marks the start of the global - constructors, and the symbol `__CTOR_END__' marks the end. - Similarly, `__DTOR_LIST__' and `__DTOR_END__' mark the start and + The symbol '__CTOR_LIST__' marks the start of the global + constructors, and the symbol '__CTOR_END__' marks the end. + Similarly, '__DTOR_LIST__' and '__DTOR_END__' mark the start and end of the global destructors. The first word in the list is the number of entries, followed by the address of each constructor or destructor, followed by a zero word. The compiler must arrange to actually run the code. For these object file formats GNU C++ - normally calls constructors from a subroutine `__main'; a call to - `__main' is automatically inserted into the startup code for - `main'. GNU C++ normally runs destructors either by using - `atexit', or directly from the function `exit'. + normally calls constructors from a subroutine '__main'; a call to + '__main' is automatically inserted into the startup code for + 'main'. GNU C++ normally runs destructors either by using + 'atexit', or directly from the function 'exit'. - For object file formats such as `COFF' or `ELF' which support + For object file formats such as 'COFF' or 'ELF' which support arbitrary section names, GNU C++ will normally arrange to put the - addresses of global constructors and destructors into the `.ctors' - and `.dtors' sections. Placing the following sequence into your + addresses of global constructors and destructors into the '.ctors' + and '.dtors' sections. Placing the following sequence into your linker script will build the sort of table which the GNU C++ runtime code expects to see. @@ -3605,16 +3572,15 @@ commands. which provides some control over the order in which global constructors are run, you must sort the constructors at link time to ensure that they are executed in the correct order. When using - the `CONSTRUCTORS' command, use `SORT_BY_NAME(CONSTRUCTORS)' - instead. When using the `.ctors' and `.dtors' sections, use - `*(SORT_BY_NAME(.ctors))' and `*(SORT_BY_NAME(.dtors))' instead of - just `*(.ctors)' and `*(.dtors)'. + the 'CONSTRUCTORS' command, use 'SORT_BY_NAME(CONSTRUCTORS)' + instead. When using the '.ctors' and '.dtors' sections, use + '*(SORT_BY_NAME(.ctors))' and '*(SORT_BY_NAME(.dtors))' instead of + just '*(.ctors)' and '*(.dtors)'. Normally the compiler and linker will handle these issues - automatically, and you will not need to concern yourself with - them. However, you may need to consider this if you are using C++ - and writing your own linker scripts. - + automatically, and you will not need to concern yourself with them. + However, you may need to consider this if you are using C++ and + writing your own linker scripts. File: ld.info, Node: Output Section Discarding, Next: Output Section Attributes, Prev: Output Section Keywords, Up: SECTIONS @@ -3626,10 +3592,10 @@ The linker will not create output sections with no contents. This is for convenience when referring to input sections that may or may not be present in any of the input files. For example: .foo : { *(.foo) } - will only create a `.foo' section in the output file if there is a -`.foo' section in at least one input file, and if the input sections -are not all empty. Other link script directives that allocate space in -an output section will also create the output section. +will only create a '.foo' section in the output file if there is a +'.foo' section in at least one input file, and if the input sections are +not all empty. Other link script directives that allocate space in an +output section will also create the output section. The linker will ignore address assignments (*note Output Section Address::) on discarded output sections, except when the linker script @@ -3637,9 +3603,9 @@ defines symbols in the output section. In that case the linker will obey the address assignments, possibly advancing dot even though the section is discarded. - The special output section name `/DISCARD/' may be used to discard + The special output section name '/DISCARD/' may be used to discard input sections. Any input sections which are assigned to an output -section named `/DISCARD/' are not included in the output file. +section named '/DISCARD/' are not included in the output file. File: ld.info, Node: Output Section Attributes, Next: Overlay Description, Prev: Output Section Discarding, Up: SECTIONS @@ -3661,9 +3627,8 @@ like this: ... } [>REGION] [AT>LMA_REGION] [:PHDR :PHDR ...] [=FILLEXP] - We've already described SECTION, ADDRESS, and -OUTPUT-SECTION-COMMAND. In this section we will describe the remaining -section attributes. + We've already described SECTION, ADDRESS, and OUTPUT-SECTION-COMMAND. +In this section we will describe the remaining section attributes. * Menu: @@ -3685,14 +3650,13 @@ File: ld.info, Node: Output Section Type, Next: Output Section LMA, Up: Outpu Each output section may have a type. The type is a keyword in parentheses. The following types are defined: -`NOLOAD' +'NOLOAD' The section should be marked as not loadable, so that it will not be loaded into memory when the program is run. - -`DSECT' -`COPY' -`INFO' -`OVERLAY' +'DSECT' +'COPY' +'INFO' +'OVERLAY' These type names are supported for backward compatibility, and are rarely used. They all have the same effect: the section should be marked as not allocatable, so that no memory is allocated for the @@ -3700,8 +3664,8 @@ parentheses. The following types are defined: The linker normally sets the attributes of an output section based on the input sections which map into it. You can override this by using -the section type. For example, in the script sample below, the `ROM' -section is addressed at memory location `0' and does not need to be +the section type. For example, in the script sample below, the 'ROM' +section is addressed at memory location '0' and does not need to be loaded when the program is run. SECTIONS { ROM 0 (NOLOAD) : { ... } @@ -3717,29 +3681,29 @@ File: ld.info, Node: Output Section LMA, Next: Forced Output Alignment, Prev: Every section has a virtual address (VMA) and a load address (LMA); see *note Basic Script Concepts::. The virtual address is specified by the *note Output Section Address:: described earlier. The load address is -specified by the `AT' or `AT>' keywords. Specifying a load address is +specified by the 'AT' or 'AT>' keywords. Specifying a load address is optional. - The `AT' keyword takes an expression as an argument. This specifies -the exact load address of the section. The `AT>' keyword takes the -name of a memory region as an argument. *Note MEMORY::. The load -address of the section is set to the next free address in the region, -aligned to the section's alignment requirements. + The 'AT' keyword takes an expression as an argument. This specifies +the exact load address of the section. The 'AT>' keyword takes the name +of a memory region as an argument. *Note MEMORY::. The load address of +the section is set to the next free address in the region, aligned to +the section's alignment requirements. - If neither `AT' nor `AT>' is specified for an allocatable section, + If neither 'AT' nor 'AT>' is specified for an allocatable section, the linker will use the following heuristic to determine the load address: - * If the section has a specific VMA address, then this is used as - the LMA address as well. + * If the section has a specific VMA address, then this is used as the + LMA address as well. * If the section is not allocatable then its LMA is set to its VMA. * Otherwise if a memory region can be found that is compatible with - the current section, and this region contains at least one - section, then the LMA is set so the difference between the VMA and - LMA is the same as the difference between the VMA and LMA of the - last section in the located region. + the current section, and this region contains at least one section, + then the LMA is set so the difference between the VMA and LMA is + the same as the difference between the VMA and LMA of the last + section in the located region. * If no memory regions have been declared then a default region that covers the entire address space is used in the previous step. @@ -3749,10 +3713,10 @@ address: This feature is designed to make it easy to build a ROM image. For example, the following linker script creates three output sections: one -called `.text', which starts at `0x1000', one called `.mdata', which is -loaded at the end of the `.text' section even though its VMA is -`0x2000', and one called `.bss' to hold uninitialized data at address -`0x3000'. The symbol `_data' is defined with the value `0x2000', which +called '.text', which starts at '0x1000', one called '.mdata', which is +loaded at the end of the '.text' section even though its VMA is +'0x2000', and one called '.bss' to hold uninitialized data at address +'0x3000'. The symbol '_data' is defined with the value '0x2000', which shows that the location counter holds the VMA value, not the LMA value. SECTIONS @@ -3789,7 +3753,11 @@ File: ld.info, Node: Forced Output Alignment, Next: Forced Input Alignment, P 3.6.8.3 Forced Output Alignment ............................... -You can increase an output section's alignment by using ALIGN. +You can increase an output section's alignment by using ALIGN. As an +alternative you can force the output section alignment to the maximum +alignment of all its input sections with ALIGN_WITH_INPUT. The alignment +forced by ALIGN_WITH_INPUT is used even in case the load and virtual +memory regions are different. File: ld.info, Node: Forced Input Alignment, Next: Output Section Constraint, Prev: Forced Output Alignment, Up: Output Section Attributes @@ -3798,7 +3766,7 @@ File: ld.info, Node: Forced Input Alignment, Next: Output Section Constraint, .............................. You can force input section alignment within an output section by using -SUBALIGN. The value specified overrides any alignment given by input +SUBALIGN. The value specified overrides any alignment given by input sections, whether larger or smaller. @@ -3809,7 +3777,7 @@ File: ld.info, Node: Output Section Constraint, Next: Output Section Region, You can specify that an output section should only be created if all of its input sections are read-only or all of its input sections are -read-write by using the keyword `ONLY_IF_RO' and `ONLY_IF_RW' +read-write by using the keyword 'ONLY_IF_RO' and 'ONLY_IF_RW' respectively. @@ -3819,7 +3787,7 @@ File: ld.info, Node: Output Section Region, Next: Output Section Phdr, Prev: ............................. You can assign a section to a previously defined region of memory by -using `>REGION'. *Note MEMORY::. +using '>REGION'. *Note MEMORY::. Here is a simple example: MEMORY { rom : ORIGIN = 0x1000, LENGTH = 0x1000 } @@ -3832,10 +3800,10 @@ File: ld.info, Node: Output Section Phdr, Next: Output Section Fill, Prev: Ou ........................... You can assign a section to a previously defined program segment by -using `:PHDR'. *Note PHDRS::. If a section is assigned to one or more +using ':PHDR'. *Note PHDRS::. If a section is assigned to one or more segments, then all subsequent allocated sections will be assigned to -those segments as well, unless they use an explicitly `:PHDR' modifier. -You can use `:NONE' to tell the linker to not put the section in any +those segments as well, unless they use an explicitly ':PHDR' modifier. +You can use ':NONE' to tell the linker to not put the section in any segment at all. Here is a simple example: @@ -3848,20 +3816,20 @@ File: ld.info, Node: Output Section Fill, Prev: Output Section Phdr, Up: Outp 3.6.8.8 Output Section Fill ........................... -You can set the fill pattern for an entire section by using `=FILLEXP'. +You can set the fill pattern for an entire section by using '=FILLEXP'. FILLEXP is an expression (*note Expressions::). Any otherwise unspecified regions of memory within the output section (for example, gaps left due to the required alignment of input sections) will be -filled with the value, repeated as necessary. If the fill expression -is a simple hex number, ie. a string of hex digit starting with `0x' -and without a trailing `k' or `M', then an arbitrarily long sequence of -hex digits can be used to specify the fill pattern; Leading zeros -become part of the pattern too. For all other cases, including extra -parentheses or a unary `+', the fill pattern is the four least +filled with the value, repeated as necessary. If the fill expression is +a simple hex number, ie. a string of hex digit starting with '0x' and +without a trailing 'k' or 'M', then an arbitrarily long sequence of hex +digits can be used to specify the fill pattern; Leading zeros become +part of the pattern too. For all other cases, including extra +parentheses or a unary '+', the fill pattern is the four least significant bytes of the value of the expression. In all cases, the number is big-endian. - You can also change the fill value with a `FILL' command in the + You can also change the fill value with a 'FILL' command in the output section commands; (*note Output Section Data::). Here is a simple example: @@ -3881,9 +3849,9 @@ required, perhaps by simply manipulating addressing bits. This approach can be useful, for example, when a certain region of memory is faster than another. - Overlays are described using the `OVERLAY' command. The `OVERLAY' -command is used within a `SECTIONS' command, like an output section -description. The full syntax of the `OVERLAY' command is as follows: + Overlays are described using the 'OVERLAY' command. The 'OVERLAY' +command is used within a 'SECTIONS' command, like an output section +description. The full syntax of the 'OVERLAY' command is as follows: OVERLAY [START] : [NOCROSSREFS] [AT ( LDADDR )] { SECNAME1 @@ -3901,60 +3869,59 @@ description. The full syntax of the `OVERLAY' command is as follows: ... } [>REGION] [:PHDR...] [=FILL] - Everything is optional except `OVERLAY' (a keyword), and each -section must have a name (SECNAME1 and SECNAME2 above). The section -definitions within the `OVERLAY' construct are identical to those -within the general `SECTIONS' construct (*note SECTIONS::), except that -no addresses and no memory regions may be defined for sections within -an `OVERLAY'. + Everything is optional except 'OVERLAY' (a keyword), and each section +must have a name (SECNAME1 and SECNAME2 above). The section definitions +within the 'OVERLAY' construct are identical to those within the general +'SECTIONS' construct (*note SECTIONS::), except that no addresses and no +memory regions may be defined for sections within an 'OVERLAY'. The sections are all defined with the same starting address. The load addresses of the sections are arranged such that they are consecutive in memory starting at the load address used for the -`OVERLAY' as a whole (as with normal section definitions, the load +'OVERLAY' as a whole (as with normal section definitions, the load address is optional, and defaults to the start address; the start address is also optional, and defaults to the current value of the location counter). - If the `NOCROSSREFS' keyword is used, and there are any references -among the sections, the linker will report an error. Since the -sections all run at the same address, it normally does not make sense -for one section to refer directly to another. *Note NOCROSSREFS: -Miscellaneous Commands. + If the 'NOCROSSREFS' keyword is used, and there are any references +among the sections, the linker will report an error. Since the sections +all run at the same address, it normally does not make sense for one +section to refer directly to another. *Note NOCROSSREFS: Miscellaneous +Commands. - For each section within the `OVERLAY', the linker automatically -provides two symbols. The symbol `__load_start_SECNAME' is defined as + For each section within the 'OVERLAY', the linker automatically +provides two symbols. The symbol '__load_start_SECNAME' is defined as the starting load address of the section. The symbol -`__load_stop_SECNAME' is defined as the final load address of the +'__load_stop_SECNAME' is defined as the final load address of the section. Any characters within SECNAME which are not legal within C -identifiers are removed. C (or assembler) code may use these symbols -to move the overlaid sections around as necessary. +identifiers are removed. C (or assembler) code may use these symbols to +move the overlaid sections around as necessary. At the end of the overlay, the value of the location counter is set to the start address of the overlay plus the size of the largest section. Here is an example. Remember that this would appear inside a -`SECTIONS' construct. +'SECTIONS' construct. OVERLAY 0x1000 : AT (0x4000) { .text0 { o1/*.o(.text) } .text1 { o2/*.o(.text) } } -This will define both `.text0' and `.text1' to start at address 0x1000. -`.text0' will be loaded at address 0x4000, and `.text1' will be loaded -immediately after `.text0'. The following symbols will be defined if -referenced: `__load_start_text0', `__load_stop_text0', -`__load_start_text1', `__load_stop_text1'. +This will define both '.text0' and '.text1' to start at address 0x1000. +'.text0' will be loaded at address 0x4000, and '.text1' will be loaded +immediately after '.text0'. The following symbols will be defined if +referenced: '__load_start_text0', '__load_stop_text0', +'__load_start_text1', '__load_stop_text1'. - C code to copy overlay `.text1' into the overlay area might look -like the following. + C code to copy overlay '.text1' into the overlay area might look like +the following. extern char __load_start_text1, __load_stop_text1; memcpy ((char *) 0x1000, &__load_start_text1, &__load_stop_text1 - &__load_start_text1); - Note that the `OVERLAY' command is just syntactic sugar, since + Note that the 'OVERLAY' command is just syntactic sugar, since everything it does can be done using the more basic commands. The above example could have been written identically as follows. @@ -3973,9 +3940,9 @@ File: ld.info, Node: MEMORY, Next: PHDRS, Prev: SECTIONS, Up: Scripts ================== The linker's default configuration permits allocation of all available -memory. You can override this by using the `MEMORY' command. +memory. You can override this by using the 'MEMORY' command. - The `MEMORY' command describes the location and size of blocks of + The 'MEMORY' command describes the location and size of blocks of memory in the target. You can use it to describe which memory regions may be used by the linker, and which memory regions it must avoid. You can then assign sections to particular memory regions. The linker will @@ -3983,7 +3950,7 @@ set section addresses based on the memory regions, and will warn about regions that become too full. The linker will not shuffle sections around to fit into the available regions. - A linker script may contain at most one use of the `MEMORY' command. + A linker script may contain at most one use of the 'MEMORY' command. However, you can define as many blocks of memory within it as you wish. The syntax is: MEMORY @@ -3996,7 +3963,7 @@ The syntax is: The region name has no meaning outside of the linker script. Region names are stored in a separate name space, and will not conflict with symbol names, file names, or section names. Each memory region must -have a distinct name within the `MEMORY' command. However you can add +have a distinct name within the 'MEMORY' command. However you can add later alias names to existing memory regions with the *note REGION_ALIAS:: command. @@ -4009,49 +3976,43 @@ the input section. If you define region attributes, the linker will use them to select the memory region for the output section that it creates. The ATTR string must consist only of the following characters: -`R' +'R' Read-only section - -`W' +'W' Read/write section - -`X' +'X' Executable section - -`A' +'A' Allocatable section - -`I' +'I' Initialized section - -`L' - Same as `I' - -`!' +'L' + Same as 'I' +'!' Invert the sense of any of the attributes that follow If a unmapped section matches any of the listed attributes other than -`!', it will be placed in the memory region. The `!' attribute -reverses this test, so that an unmapped section will be placed in the -memory region only if it does not match any of the listed attributes. +'!', it will be placed in the memory region. The '!' attribute reverses +this test, so that an unmapped section will be placed in the memory +region only if it does not match any of the listed attributes. The ORIGIN is an numerical expression for the start address of the -memory region. The expression must evaluate to a constant and it -cannot involve any symbols. The keyword `ORIGIN' may be abbreviated to -`org' or `o' (but not, for example, `ORG'). +memory region. The expression must evaluate to a constant and it cannot +involve any symbols. The keyword 'ORIGIN' may be abbreviated to 'org' +or 'o' (but not, for example, 'ORG'). The LEN is an expression for the size in bytes of the memory region. -As with the ORIGIN expression, the expression must be numerical only -and must evaluate to a constant. The keyword `LENGTH' may be -abbreviated to `len' or `l'. +As with the ORIGIN expression, the expression must be numerical only and +must evaluate to a constant. The keyword 'LENGTH' may be abbreviated to +'len' or 'l'. In the following example, we specify that there are two memory -regions available for allocation: one starting at `0' for 256 kilobytes, -and the other starting at `0x40000000' for four megabytes. The linker -will place into the `rom' memory region every section which is not +regions available for allocation: one starting at '0' for 256 kilobytes, +and the other starting at '0x40000000' for four megabytes. The linker +will place into the 'rom' memory region every section which is not explicitly mapped into a memory region, and is either read-only or executable. The linker will place other sections which are not -explicitly mapped into a memory region into the `ram' memory region. +explicitly mapped into a memory region into the 'ram' memory region. MEMORY { @@ -4060,9 +4021,9 @@ explicitly mapped into a memory region into the `ram' memory region. } Once you define a memory region, you can direct the linker to place -specific output sections into that memory region by using the `>REGION' +specific output sections into that memory region by using the '>REGION' output section attribute. For example, if you have a memory region -named `mem', you would use `>mem' in the output section definition. +named 'mem', you would use '>mem' in the output section definition. *Note Output Section Region::. If no address was specified for the output section, the linker will set the address to the next available address within the memory region. If the combined output sections @@ -4070,7 +4031,7 @@ directed to a memory region are too large for the region, the linker will issue an error message. It is possible to access the origin and length of a memory in an -expression via the `ORIGIN(MEMORY)' and `LENGTH(MEMORY)' functions: +expression via the 'ORIGIN(MEMORY)' and 'LENGTH(MEMORY)' functions: _fstack = ORIGIN(ram) + LENGTH(ram) - 4; @@ -4082,8 +4043,8 @@ File: ld.info, Node: PHDRS, Next: VERSION, Prev: MEMORY, Up: Scripts The ELF object file format uses "program headers", also knows as "segments". The program headers describe how the program should be -loaded into memory. You can print them out by using the `objdump' -program with the `-p' option. +loaded into memory. You can print them out by using the 'objdump' +program with the '-p' option. When you run an ELF program on a native ELF system, the system loader reads the program headers in order to figure out how to load the @@ -4093,16 +4054,16 @@ interprets program headers; for more information, see the ELF ABI. The linker will create reasonable program headers by default. However, in some cases, you may need to specify the program headers more -precisely. You may use the `PHDRS' command for this purpose. When the -linker sees the `PHDRS' command in the linker script, it will not -create any program headers other than the ones specified. +precisely. You may use the 'PHDRS' command for this purpose. When the +linker sees the 'PHDRS' command in the linker script, it will not create +any program headers other than the ones specified. - The linker only pays attention to the `PHDRS' command when -generating an ELF output file. In other cases, the linker will simply -ignore `PHDRS'. + The linker only pays attention to the 'PHDRS' command when generating +an ELF output file. In other cases, the linker will simply ignore +'PHDRS'. - This is the syntax of the `PHDRS' command. The words `PHDRS', -`FILEHDR', `AT', and `FLAGS' are keywords. + This is the syntax of the 'PHDRS' command. The words 'PHDRS', +'FILEHDR', 'AT', and 'FLAGS' are keywords. PHDRS { @@ -4110,7 +4071,7 @@ ignore `PHDRS'. [ FLAGS ( FLAGS ) ] ; } - The NAME is used only for reference in the `SECTIONS' command of the + The NAME is used only for reference in the 'SECTIONS' command of the linker script. It is not put into the output file. Program header names are stored in a separate name space, and will not conflict with symbol names, file names, or section names. Each program header must @@ -4120,55 +4081,55 @@ usual for them to map to sections in ascending load address order. Certain program header types describe segments of memory which the system loader will load from the file. In the linker script, you specify the contents of these segments by placing allocatable output -sections in the segments. You use the `:PHDR' output section attribute +sections in the segments. You use the ':PHDR' output section attribute to place a section in a particular segment. *Note Output Section Phdr::. It is normal to put certain sections in more than one segment. This merely implies that one segment of memory contains another. You may -repeat `:PHDR', using it once for each segment which should contain the +repeat ':PHDR', using it once for each segment which should contain the section. - If you place a section in one or more segments using `:PHDR', then + If you place a section in one or more segments using ':PHDR', then the linker will place all subsequent allocatable sections which do not -specify `:PHDR' in the same segments. This is for convenience, since +specify ':PHDR' in the same segments. This is for convenience, since generally a whole set of contiguous sections will be placed in a single -segment. You can use `:NONE' to override the default segment and tell +segment. You can use ':NONE' to override the default segment and tell the linker to not put the section in any segment at all. - You may use the `FILEHDR' and `PHDRS' keywords after the program + You may use the 'FILEHDR' and 'PHDRS' keywords after the program header type to further describe the contents of the segment. The -`FILEHDR' keyword means that the segment should include the ELF file -header. The `PHDRS' keyword means that the segment should include the +'FILEHDR' keyword means that the segment should include the ELF file +header. The 'PHDRS' keyword means that the segment should include the ELF program headers themselves. If applied to a loadable segment -(`PT_LOAD'), all prior loadable segments must have one of these +('PT_LOAD'), all prior loadable segments must have one of these keywords. - The TYPE may be one of the following. The numbers indicate the -value of the keyword. + The TYPE may be one of the following. The numbers indicate the value +of the keyword. -`PT_NULL' (0) +'PT_NULL' (0) Indicates an unused program header. -`PT_LOAD' (1) - Indicates that this program header describes a segment to be - loaded from the file. +'PT_LOAD' (1) + Indicates that this program header describes a segment to be loaded + from the file. -`PT_DYNAMIC' (2) +'PT_DYNAMIC' (2) Indicates a segment where dynamic linking information can be found. -`PT_INTERP' (3) +'PT_INTERP' (3) Indicates a segment where the name of the program interpreter may be found. -`PT_NOTE' (4) +'PT_NOTE' (4) Indicates a segment holding note information. -`PT_SHLIB' (5) +'PT_SHLIB' (5) A reserved program header type, defined but not specified by the ELF ABI. -`PT_PHDR' (6) +'PT_PHDR' (6) Indicates a segment where the program headers may be found. EXPRESSION @@ -4176,17 +4137,17 @@ EXPRESSION may be used for types not defined above. You can specify that a segment should be loaded at a particular -address in memory by using an `AT' expression. This is identical to the -`AT' command used as an output section attribute (*note Output Section -LMA::). The `AT' command for a program header overrides the output +address in memory by using an 'AT' expression. This is identical to the +'AT' command used as an output section attribute (*note Output Section +LMA::). The 'AT' command for a program header overrides the output section attribute. The linker will normally set the segment flags based on the sections -which comprise the segment. You may use the `FLAGS' keyword to +which comprise the segment. You may use the 'FLAGS' keyword to explicitly specify the segment flags. The value of FLAGS must be an -integer. It is used to set the `p_flags' field of the program header. +integer. It is used to set the 'p_flags' field of the program header. - Here is an example of `PHDRS'. This shows a typical set of program + Here is an example of 'PHDRS'. This shows a typical set of program headers used on a native ELF system. PHDRS @@ -4217,7 +4178,7 @@ File: ld.info, Node: VERSION, Next: Expressions, Prev: PHDRS, Up: Scripts 3.9 VERSION Command =================== -The linker supports symbol versions when using ELF. Symbol versions are +The linker supports symbol versions when using ELF. Symbol versions are only useful when using shared libraries. The dynamic linker can use symbol versions to select a specific version of a function when it runs a program that may have been linked against an earlier version of the @@ -4225,9 +4186,9 @@ shared library. You can include a version script directly in the main linker script, or you can supply the version script as an implicit linker script. You -can also use the `--version-script' linker option. +can also use the '--version-script' linker option. - The syntax of the `VERSION' command is simply + The syntax of the 'VERSION' command is simply VERSION { version-script-commands } The format of the version script commands is identical to that used @@ -4259,32 +4220,32 @@ few examples. extern "C++" { ns::*; "f(int, double)"; - }; + }; } VERS_1.2; This example version script defines three version nodes. The first -version node defined is `VERS_1.1'; it has no other dependencies. The -script binds the symbol `foo1' to `VERS_1.1'. It reduces a number of +version node defined is 'VERS_1.1'; it has no other dependencies. The +script binds the symbol 'foo1' to 'VERS_1.1'. It reduces a number of symbols to local scope so that they are not visible outside of the -shared library; this is done using wildcard patterns, so that any -symbol whose name begins with `old', `original', or `new' is matched. -The wildcard patterns available are the same as those used in the shell -when matching filenames (also known as "globbing"). However, if you -specify the symbol name inside double quotes, then the name is treated -as literal, rather than as a glob pattern. +shared library; this is done using wildcard patterns, so that any symbol +whose name begins with 'old', 'original', or 'new' is matched. The +wildcard patterns available are the same as those used in the shell when +matching filenames (also known as "globbing"). However, if you specify +the symbol name inside double quotes, then the name is treated as +literal, rather than as a glob pattern. - Next, the version script defines node `VERS_1.2'. This node depends -upon `VERS_1.1'. The script binds the symbol `foo2' to the version -node `VERS_1.2'. + Next, the version script defines node 'VERS_1.2'. This node depends +upon 'VERS_1.1'. The script binds the symbol 'foo2' to the version node +'VERS_1.2'. - Finally, the version script defines node `VERS_2.0'. This node -depends upon `VERS_1.2'. The scripts binds the symbols `bar1' and -`bar2' are bound to the version node `VERS_2.0'. + Finally, the version script defines node 'VERS_2.0'. This node +depends upon 'VERS_1.2'. The scripts binds the symbols 'bar1' and +'bar2' are bound to the version node 'VERS_2.0'. When the linker finds a symbol defined in a library which is not specifically bound to a version node, it will effectively bind it to an unspecified base version of the library. You can bind all otherwise -unspecified symbols to a given version node by using `global: *;' +unspecified symbols to a given version node by using 'global: *;' somewhere in the version script. Note that it's slightly crazy to use wildcards in a global spec except on the last version node. Global wildcards elsewhere run the risk of accidentally adding symbols to the @@ -4292,12 +4253,12 @@ set exported for an old version. That's wrong since older versions ought to have a fixed set of symbols. The names of the version nodes have no specific meaning other than -what they might suggest to the person reading them. The `2.0' version -could just as well have appeared in between `1.1' and `1.2'. However, +what they might suggest to the person reading them. The '2.0' version +could just as well have appeared in between '1.1' and '1.2'. However, this would be a confusing way to write a version script. - Node name can be omitted, provided it is the only version node in -the version script. Such version script doesn't assign any versions to + Node name can be omitted, provided it is the only version node in the +version script. Such version script doesn't assign any versions to symbols, only selects which symbols will be globally visible out and which won't. @@ -4330,11 +4291,10 @@ source file where the symbol is defined instead of in the versioning script. This was done mainly to reduce the burden on the library maintainer. You can do this by putting something like: __asm__(".symver original_foo,foo@VERS_1.1"); - in the C source file. This renames the function `original_foo' to -be an alias for `foo' bound to the version node `VERS_1.1'. The -`local:' directive can be used to prevent the symbol `original_foo' -from being exported. A `.symver' directive takes precedence over a -version script. +in the C source file. This renames the function 'original_foo' to be an +alias for 'foo' bound to the version node 'VERS_1.1'. The 'local:' +directive can be used to prevent the symbol 'original_foo' from being +exported. A '.symver' directive takes precedence over a version script. The second GNU extension is to allow multiple versions of the same function to appear in a given shared library. In this way you can make @@ -4342,7 +4302,7 @@ an incompatible change to an interface without increasing the major version number of the shared library, while still allowing applications linked against the old interface to continue to function. - To do this, you must use multiple `.symver' directives in the source + To do this, you must use multiple '.symver' directives in the source file. Here is an example: __asm__(".symver original_foo,foo@"); @@ -4350,36 +4310,36 @@ file. Here is an example: __asm__(".symver old_foo1,foo@VERS_1.2"); __asm__(".symver new_foo,foo@@VERS_2.0"); - In this example, `foo@' represents the symbol `foo' bound to the + In this example, 'foo@' represents the symbol 'foo' bound to the unspecified base version of the symbol. The source file that contains -this example would define 4 C functions: `original_foo', `old_foo', -`old_foo1', and `new_foo'. +this example would define 4 C functions: 'original_foo', 'old_foo', +'old_foo1', and 'new_foo'. When you have multiple definitions of a given symbol, there needs to be some way to specify a default version to which external references to -this symbol will be bound. You can do this with the `foo@@VERS_2.0' -type of `.symver' directive. You can only declare one version of a +this symbol will be bound. You can do this with the 'foo@@VERS_2.0' +type of '.symver' directive. You can only declare one version of a symbol as the default in this manner; otherwise you would effectively have multiple definitions of the same symbol. If you wish to bind a reference to a specific version of the symbol -within the shared library, you can use the aliases of convenience -(i.e., `old_foo'), or you can use the `.symver' directive to -specifically bind to an external version of the function in question. +within the shared library, you can use the aliases of convenience (i.e., +'old_foo'), or you can use the '.symver' directive to specifically bind +to an external version of the function in question. You can also specify the language in the version script: VERSION extern "lang" { version-script-commands } - The supported `lang's are `C', `C++', and `Java'. The linker will + The supported 'lang's are 'C', 'C++', and 'Java'. The linker will iterate over the list of symbols at the link time and demangle them -according to `lang' before matching them to the patterns specified in -`version-script-commands'. The default `lang' is `C'. +according to 'lang' before matching them to the patterns specified in +'version-script-commands'. The default 'lang' is 'C'. Demangled names may contains spaces and other special characters. As -described above, you can use a glob pattern to match demangled names, -or you can use a double-quoted string to match the string exactly. In -the latter case, be aware that minor differences (such as differing +described above, you can use a glob pattern to match demangled names, or +you can use a double-quoted string to match the string exactly. In the +latter case, be aware that minor differences (such as differing whitespace) between the version script and the demangler output will cause a mismatch. As the exact string generated by the demangler might change in the future, even if the mangled name does not, you should @@ -4422,23 +4382,23 @@ File: ld.info, Node: Constants, Next: Symbolic Constants, Up: Expressions All constants are integers. - As in C, the linker considers an integer beginning with `0' to be -octal, and an integer beginning with `0x' or `0X' to be hexadecimal. -Alternatively the linker accepts suffixes of `h' or `H' for -hexadecimal, `o' or `O' for octal, `b' or `B' for binary and `d' or `D' -for decimal. Any integer value without a prefix or a suffix is -considered to be decimal. + As in C, the linker considers an integer beginning with '0' to be +octal, and an integer beginning with '0x' or '0X' to be hexadecimal. +Alternatively the linker accepts suffixes of 'h' or 'H' for hexadecimal, +'o' or 'O' for octal, 'b' or 'B' for binary and 'd' or 'D' for decimal. +Any integer value without a prefix or a suffix is considered to be +decimal. - In addition, you can use the suffixes `K' and `M' to scale a -constant by `1024' or `1024*1024' respectively. For example, the -following all refer to the same quantity: + In addition, you can use the suffixes 'K' and 'M' to scale a constant +by '1024' or '1024*1024' respectively. For example, the following all +refer to the same quantity: _fourk_1 = 4K; _fourk_2 = 4096; _fourk_3 = 0x1000; _fourk_4 = 10000o; - Note - the `K' and `M' suffixes cannot be used in conjunction with + Note - the 'K' and 'M' suffixes cannot be used in conjunction with the base suffixes mentioned above. @@ -4448,12 +4408,12 @@ File: ld.info, Node: Symbolic Constants, Next: Symbols, Prev: Constants, Up: ------------------------- It is possible to refer to target specific constants via the use of the -`CONSTANT(NAME)' operator, where NAME is one of: +'CONSTANT(NAME)' operator, where NAME is one of: -`MAXPAGESIZE' +'MAXPAGESIZE' The target's maximum page size. -`COMMONPAGESIZE' +'COMMONPAGESIZE' The target's default page size. So for example: @@ -4478,8 +4438,8 @@ keyword by surrounding the symbol name in double quotes: "with a space" = "also with a space" + 10; Since symbols can contain many non-alphabetic characters, it is -safest to delimit symbols with spaces. For example, `A-B' is one -symbol, whereas `A - B' is an expression involving subtraction. +safest to delimit symbols with spaces. For example, 'A-B' is one +symbol, whereas 'A - B' is an expression involving subtraction. File: ld.info, Node: Orphan Sections, Next: Location Counter, Prev: Symbols, Up: Expressions @@ -4488,13 +4448,13 @@ File: ld.info, Node: Orphan Sections, Next: Location Counter, Prev: Symbols, ---------------------- Orphan sections are sections present in the input files which are not -explicitly placed into the output file by the linker script. The -linker will still copy these sections into the output file, but it has -to guess as to where they should be placed. The linker uses a simple -heuristic to do this. It attempts to place orphan sections after -non-orphan sections of the same attribute, such as code vs data, -loadable vs non-loadable, etc. If there is not enough room to do this -then it places at the end of the file. +explicitly placed into the output file by the linker script. The linker +will still copy these sections into the output file, but it has to guess +as to where they should be placed. The linker uses a simple heuristic +to do this. It attempts to place orphan sections after non-orphan +sections of the same attribute, such as code vs data, loadable vs +non-loadable, etc. If there is not enough room to do this then it +places at the end of the file. For ELF targets, the attribute of the section includes section type as well as section flag. @@ -4504,7 +4464,7 @@ the linker will automatically *note PROVIDE:: two symbols: __start_SECNAME and __stop_SECNAME, where SECNAME is the name of the section. These indicate the start address and end address of the orphaned section respectively. Note: most section names are not -representable as C identifiers because they contain a `.' character. +representable as C identifiers because they contain a '.' character. File: ld.info, Node: Location Counter, Next: Operators, Prev: Orphan Sections, Up: Expressions @@ -4512,17 +4472,17 @@ File: ld.info, Node: Location Counter, Next: Operators, Prev: Orphan Sections 3.10.5 The Location Counter --------------------------- -The special linker variable "dot" `.' always contains the current -output location counter. Since the `.' always refers to a location in -an output section, it may only appear in an expression within a -`SECTIONS' command. The `.' symbol may appear anywhere that an -ordinary symbol is allowed in an expression. +The special linker variable "dot" '.' always contains the current output +location counter. Since the '.' always refers to a location in an +output section, it may only appear in an expression within a 'SECTIONS' +command. The '.' symbol may appear anywhere that an ordinary symbol is +allowed in an expression. - Assigning a value to `.' will cause the location counter to be -moved. This may be used to create holes in the output section. The -location counter may not be moved backwards inside an output section, -and may not be moved backwards outside of an output section if so doing -creates areas with overlapping LMAs. + Assigning a value to '.' will cause the location counter to be moved. +This may be used to create holes in the output section. The location +counter may not be moved backwards inside an output section, and may not +be moved backwards outside of an output section if so doing creates +areas with overlapping LMAs. SECTIONS { @@ -4535,17 +4495,17 @@ creates areas with overlapping LMAs. file3(.text) } = 0x12345678; } - In the previous example, the `.text' section from `file1' is located -at the beginning of the output section `output'. It is followed by a -1000 byte gap. Then the `.text' section from `file2' appears, also -with a 1000 byte gap following before the `.text' section from `file3'. -The notation `= 0x12345678' specifies what data to write in the gaps -(*note Output Section Fill::). - - Note: `.' actually refers to the byte offset from the start of the -current containing object. Normally this is the `SECTIONS' statement, -whose start address is 0, hence `.' can be used as an absolute address. -If `.' is used inside a section description however, it refers to the +In the previous example, the '.text' section from 'file1' is located at +the beginning of the output section 'output'. It is followed by a 1000 +byte gap. Then the '.text' section from 'file2' appears, also with a +1000 byte gap following before the '.text' section from 'file3'. The +notation '= 0x12345678' specifies what data to write in the gaps (*note +Output Section Fill::). + + Note: '.' actually refers to the byte offset from the start of the +current containing object. Normally this is the 'SECTIONS' statement, +whose start address is 0, hence '.' can be used as an absolute address. +If '.' is used inside a section description however, it refers to the byte offset from the start of that section, not an absolute address. Thus in a script like this: @@ -4563,14 +4523,14 @@ Thus in a script like this: } } - The `.text' section will be assigned a starting address of 0x100 and + The '.text' section will be assigned a starting address of 0x100 and a size of exactly 0x200 bytes, even if there is not enough data in the -`.text' input sections to fill this area. (If there is too much data, -an error will be produced because this would be an attempt to move `.' -backwards). The `.data' section will start at 0x500 and it will have -an extra 0x600 bytes worth of space after the end of the values from -the `.data' input sections and before the end of the `.data' output -section itself. +'.text' input sections to fill this area. (If there is too much data, +an error will be produced because this would be an attempt to move '.' +backwards). The '.data' section will start at 0x500 and it will have an +extra 0x600 bytes worth of space after the end of the values from the +'.data' input sections and before the end of the '.data' output section +itself. Setting symbols to the value of the location counter outside of an output section statement can result in unexpected values if the linker @@ -4587,15 +4547,15 @@ needs to place orphan sections. For example, given the following: end_of_data = . ; } - If the linker needs to place some input section, e.g. `.rodata', not + If the linker needs to place some input section, e.g. '.rodata', not mentioned in the script, it might choose to place that section between -`.text' and `.data'. You might think the linker should place `.rodata' +'.text' and '.data'. You might think the linker should place '.rodata' on the blank line in the above script, but blank lines are of no particular significance to the linker. As well, the linker doesn't associate the above symbol names with their sections. Instead, it assumes that all assignments or other statements belong to the previous -output section, except for the special case of an assignment to `.'. -I.e., the linker will place the orphan `.rodata' section as if the +output section, except for the special case of an assignment to '.'. +I.e., the linker will place the orphan '.rodata' section as if the script was written as follows: SECTIONS @@ -4611,9 +4571,9 @@ script was written as follows: } This may or may not be the script author's intention for the value of -`start_of_data'. One way to influence the orphan section placement is +'start_of_data'. One way to influence the orphan section placement is to assign the location counter to itself, as the linker assumes that an -assignment to `.' is setting the start address of a following output +assignment to '.' is setting the start address of a following output section and thus should be grouped with that section. So you could write: @@ -4629,8 +4589,8 @@ write: end_of_data = . ; } - Now, the orphan `.rodata' section will be placed between -`end_of_text' and `start_of_data'. + Now, the orphan '.rodata' section will be placed between +'end_of_text' and 'start_of_data'. File: ld.info, Node: Operators, Next: Evaluation, Prev: Location Counter, Up: Expressions @@ -4680,7 +4640,7 @@ assignments dependent upon these are not performed until after allocation. Some expressions, such as those depending upon the location counter -`.', must be evaluated during section allocation. +'.', must be evaluated during section allocation. If the result of an expression is required, but the value is not available, then an error results. For example, a script like the @@ -4690,7 +4650,7 @@ following .text 9+this_isnt_constant : { *(.text) } } -will cause the error message `non constant expression for initial +will cause the error message 'non constant expression for initial address'. @@ -4700,22 +4660,22 @@ File: ld.info, Node: Expression Section, Next: Builtin Functions, Prev: Evalu ----------------------------------- Addresses and symbols may be section relative, or absolute. A section -relative symbol is relocatable. If you request relocatable output -using the `-r' option, a further link operation may change the value of -a section relative symbol. On the other hand, an absolute symbol will +relative symbol is relocatable. If you request relocatable output using +the '-r' option, a further link operation may change the value of a +section relative symbol. On the other hand, an absolute symbol will retain the same value throughout any further link operations. Some terms in linker expressions are addresses. This is true of section relative symbols and for builtin functions that return an -address, such as `ADDR', `LOADADDR', `ORIGIN' and `SEGMENT_START'. +address, such as 'ADDR', 'LOADADDR', 'ORIGIN' and 'SEGMENT_START'. Other terms are simply numbers, or are builtin functions that return a -non-address value, such as `LENGTH'. One complication is that unless -you set `LD_FEATURE ("SANE_EXPR")' (*note Miscellaneous Commands::), +non-address value, such as 'LENGTH'. One complication is that unless +you set 'LD_FEATURE ("SANE_EXPR")' (*note Miscellaneous Commands::), numbers and absolute symbols are treated differently depending on their -location, for compatibility with older versions of `ld'. Expressions +location, for compatibility with older versions of 'ld'. Expressions appearing outside an output section definition treat all numbers as absolute addresses. Expressions appearing inside an output section -definition treat absolute symbols as numbers. If `LD_FEATURE +definition treat absolute symbols as numbers. If 'LD_FEATURE ("SANE_EXPR")' is given, then absolute symbols and numbers are simply treated as numbers everywhere. @@ -4734,9 +4694,9 @@ treated as numbers everywhere. ... } - both `.' and `__executable_start' are set to the absolute address -0x100 in the first two assignments, then both `.' and `__data_start' -are set to 0x10 relative to the `.data' section in the second two + both '.' and '__executable_start' are set to the absolute address +0x100 in the first two assignments, then both '.' and '__data_start' are +set to 0x10 relative to the '.data' section in the second two assignments. For expressions involving numbers, relative addresses and absolute @@ -4745,12 +4705,10 @@ addresses, ld follows these rules to evaluate terms: * Unary operations on an absolute address or number, and binary operations on two absolute addresses or two numbers, or between one absolute address and a number, apply the operator to the value(s). - * Unary operations on a relative address, and binary operations on two relative addresses in the same section or between one relative address and a number, apply the operator to the offset part of the address(es). - * Other binary operations, that is, between two relative addresses not in the same section, or between a relative address and an absolute address, first convert any non-absolute term to an @@ -4759,32 +4717,28 @@ addresses, ld follows these rules to evaluate terms: The result section of each sub-expression is as follows: * An operation involving only numbers results in a number. - - * The result of comparisons, `&&' and `||' is also a number. - + * The result of comparisons, '&&' and '||' is also a number. * The result of other binary arithmetic and logical operations on two relative addresses in the same section or two absolute addresses (after above conversions) is also a number. - * The result of other operations on relative addresses or one relative address and a number, is a relative address in the same section as the relative operand(s). - * The result of other operations on absolute addresses (after above conversions) is an absolute address. - You can use the builtin function `ABSOLUTE' to force an expression -to be absolute when it would otherwise be relative. For example, to -create an absolute symbol set to the address of the end of the output -section `.data': + You can use the builtin function 'ABSOLUTE' to force an expression to +be absolute when it would otherwise be relative. For example, to create +an absolute symbol set to the address of the end of the output section +'.data': SECTIONS { .data : { *(.data) _edata = ABSOLUTE(.); } } - If `ABSOLUTE' were not used, `_edata' would be relative to the -`.data' section. +If 'ABSOLUTE' were not used, '_edata' would be relative to the '.data' +section. - Using `LOADADDR' also forces an expression absolute, since this + Using 'LOADADDR' also forces an expression absolute, since this particular builtin function returns an absolute address. @@ -4796,19 +4750,19 @@ File: ld.info, Node: Builtin Functions, Prev: Expression Section, Up: Express The linker script language includes a number of builtin functions for use in linker script expressions. -`ABSOLUTE(EXP)' +'ABSOLUTE(EXP)' Return the absolute (non-relocatable, as opposed to non-negative) value of the expression EXP. Primarily useful to assign an absolute value to a symbol within a section definition, where symbol values are normally section relative. *Note Expression Section::. -`ADDR(SECTION)' +'ADDR(SECTION)' Return the address (VMA) of the named SECTION. Your script must previously have defined the location of that section. In the - following example, `start_of_output_1', `symbol_1' and `symbol_2' - are assigned equivalent values, except that `symbol_1' will be - relative to the `.output1' section while the other two will be + following example, 'start_of_output_1', 'symbol_1' and 'symbol_2' + are assigned equivalent values, except that 'symbol_1' will be + relative to the '.output1' section while the other two will be absolute: SECTIONS { ... .output1 : @@ -4823,18 +4777,18 @@ use in linker script expressions. } ... } -`ALIGN(ALIGN)' -`ALIGN(EXP,ALIGN)' - Return the location counter (`.') or arbitrary expression aligned - to the next ALIGN boundary. The single operand `ALIGN' doesn't +'ALIGN(ALIGN)' +'ALIGN(EXP,ALIGN)' + Return the location counter ('.') or arbitrary expression aligned + to the next ALIGN boundary. The single operand 'ALIGN' doesn't change the value of the location counter--it just does arithmetic - on it. The two operand `ALIGN' allows an arbitrary expression to - be aligned upwards (`ALIGN(ALIGN)' is equivalent to `ALIGN(., + on it. The two operand 'ALIGN' allows an arbitrary expression to + be aligned upwards ('ALIGN(ALIGN)' is equivalent to 'ALIGN(., ALIGN)'). - Here is an example which aligns the output `.data' section to the - next `0x2000' byte boundary after the preceding section and sets a - variable within the section to the next `0x8000' boundary after the + Here is an example which aligns the output '.data' section to the + next '0x2000' byte boundary after the preceding section and sets a + variable within the section to the next '0x8000' boundary after the input sections: SECTIONS { ... .data ALIGN(0x2000): { @@ -4842,19 +4796,19 @@ use in linker script expressions. variable = ALIGN(0x8000); } ... } - The first use of `ALIGN' in this example specifies the location of - a section because it is used as the optional ADDRESS attribute of - a section definition (*note Output Section Address::). The second - use of `ALIGN' is used to defines the value of a symbol. - - The builtin function `NEXT' is closely related to `ALIGN'. - -`ALIGNOF(SECTION)' - Return the alignment in bytes of the named SECTION, if that - section has been allocated. If the section has not been allocated - when this is evaluated, the linker will report an error. In the - following example, the alignment of the `.output' section is - stored as the first value in that section. + The first use of 'ALIGN' in this example specifies the location of + a section because it is used as the optional ADDRESS attribute of a + section definition (*note Output Section Address::). The second + use of 'ALIGN' is used to defines the value of a symbol. + + The builtin function 'NEXT' is closely related to 'ALIGN'. + +'ALIGNOF(SECTION)' + Return the alignment in bytes of the named SECTION, if that section + has been allocated. If the section has not been allocated when + this is evaluated, the linker will report an error. In the + following example, the alignment of the '.output' section is stored + as the first value in that section. SECTIONS{ ... .output { LONG (ALIGNOF (.output)) @@ -4862,56 +4816,56 @@ use in linker script expressions. } ... } -`BLOCK(EXP)' - This is a synonym for `ALIGN', for compatibility with older linker +'BLOCK(EXP)' + This is a synonym for 'ALIGN', for compatibility with older linker scripts. It is most often seen when setting the address of an output section. -`DATA_SEGMENT_ALIGN(MAXPAGESIZE, COMMONPAGESIZE)' +'DATA_SEGMENT_ALIGN(MAXPAGESIZE, COMMONPAGESIZE)' This is equivalent to either (ALIGN(MAXPAGESIZE) + (. & (MAXPAGESIZE - 1))) or (ALIGN(MAXPAGESIZE) + (. & (MAXPAGESIZE - COMMONPAGESIZE))) depending on whether the latter uses fewer COMMONPAGESIZE sized pages for the data segment (area between the result of this - expression and `DATA_SEGMENT_END') than the former or not. If the + expression and 'DATA_SEGMENT_END') than the former or not. If the latter form is used, it means COMMONPAGESIZE bytes of runtime memory will be saved at the expense of up to COMMONPAGESIZE wasted bytes in the on-disk file. - This expression can only be used directly in `SECTIONS' commands, + This expression can only be used directly in 'SECTIONS' commands, not in any output section descriptions and only once in the linker script. COMMONPAGESIZE should be less or equal to MAXPAGESIZE and - should be the system page size the object wants to be optimized - for (while still working on system page sizes up to MAXPAGESIZE). + should be the system page size the object wants to be optimized for + (while still working on system page sizes up to MAXPAGESIZE). Example: . = DATA_SEGMENT_ALIGN(0x10000, 0x2000); -`DATA_SEGMENT_END(EXP)' - This defines the end of data segment for `DATA_SEGMENT_ALIGN' +'DATA_SEGMENT_END(EXP)' + This defines the end of data segment for 'DATA_SEGMENT_ALIGN' evaluation purposes. . = DATA_SEGMENT_END(.); -`DATA_SEGMENT_RELRO_END(OFFSET, EXP)' - This defines the end of the `PT_GNU_RELRO' segment when `-z relro' - option is used. Second argument is returned. When `-z relro' - option is not present, `DATA_SEGMENT_RELRO_END' does nothing, - otherwise `DATA_SEGMENT_ALIGN' is padded so that EXP + OFFSET is +'DATA_SEGMENT_RELRO_END(OFFSET, EXP)' + This defines the end of the 'PT_GNU_RELRO' segment when '-z relro' + option is used. Second argument is returned. When '-z relro' + option is not present, 'DATA_SEGMENT_RELRO_END' does nothing, + otherwise 'DATA_SEGMENT_ALIGN' is padded so that EXP + OFFSET is aligned to the most commonly used page boundary for particular target. If present in the linker script, it must always come in - between `DATA_SEGMENT_ALIGN' and `DATA_SEGMENT_END'. + between 'DATA_SEGMENT_ALIGN' and 'DATA_SEGMENT_END'. . = DATA_SEGMENT_RELRO_END(24, .); -`DEFINED(SYMBOL)' +'DEFINED(SYMBOL)' Return 1 if SYMBOL is in the linker global symbol table and is defined before the statement using DEFINED in the script, otherwise return 0. You can use this function to provide default values for symbols. For example, the following script fragment shows how to - set a global symbol `begin' to the first location in the `.text' - section--but if a symbol called `begin' already existed, its value + set a global symbol 'begin' to the first location in the '.text' + section--but if a symbol called 'begin' already existed, its value is preserved: SECTIONS { ... @@ -4922,41 +4876,45 @@ use in linker script expressions. ... } -`LENGTH(MEMORY)' +'LENGTH(MEMORY)' Return the length of the memory region named MEMORY. -`LOADADDR(SECTION)' +'LOADADDR(SECTION)' Return the absolute LMA of the named SECTION. (*note Output Section LMA::). -`MAX(EXP1, EXP2)' +'LOG2CEIL(EXP)' + Return the binary logarithm of EXP rounded towards infinity. + 'LOG2CEIL(0)' returns 0. + +'MAX(EXP1, EXP2)' Returns the maximum of EXP1 and EXP2. -`MIN(EXP1, EXP2)' +'MIN(EXP1, EXP2)' Returns the minimum of EXP1 and EXP2. -`NEXT(EXP)' +'NEXT(EXP)' Return the next unallocated address that is a multiple of EXP. - This function is closely related to `ALIGN(EXP)'; unless you use - the `MEMORY' command to define discontinuous memory for the output + This function is closely related to 'ALIGN(EXP)'; unless you use + the 'MEMORY' command to define discontinuous memory for the output file, the two functions are equivalent. -`ORIGIN(MEMORY)' +'ORIGIN(MEMORY)' Return the origin of the memory region named MEMORY. -`SEGMENT_START(SEGMENT, DEFAULT)' - Return the base address of the named SEGMENT. If an explicit - value has been given for this segment (with a command-line `-T' - option) that value will be returned; otherwise the value will be - DEFAULT. At present, the `-T' command-line option can only be +'SEGMENT_START(SEGMENT, DEFAULT)' + Return the base address of the named SEGMENT. If an explicit value + has already been given for this segment (with a command-line '-T' + option) then that value will be returned otherwise the value will + be DEFAULT. At present, the '-T' command-line option can only be used to set the base address for the "text", "data", and "bss" - sections, but you can use `SEGMENT_START' with any segment name. + sections, but you can use 'SEGMENT_START' with any segment name. -`SIZEOF(SECTION)' +'SIZEOF(SECTION)' Return the size in bytes of the named SECTION, if that section has been allocated. If the section has not been allocated when this is evaluated, the linker will report an error. In the following - example, `symbol_1' and `symbol_2' are assigned identical values: + example, 'symbol_1' and 'symbol_2' are assigned identical values: SECTIONS{ ... .output { .start = . ; @@ -4967,23 +4925,23 @@ use in linker script expressions. symbol_2 = SIZEOF(.output); ... } -`SIZEOF_HEADERS' -`sizeof_headers' +'SIZEOF_HEADERS' +'sizeof_headers' Return the size in bytes of the output file's headers. This is - information which appears at the start of the output file. You - can use this number when setting the start address of the first + information which appears at the start of the output file. You can + use this number when setting the start address of the first section, if you choose, to facilitate paging. When producing an ELF output file, if the linker script uses the - `SIZEOF_HEADERS' builtin function, the linker must compute the + 'SIZEOF_HEADERS' builtin function, the linker must compute the number of program headers before it has determined all the section addresses and sizes. If the linker later discovers that it needs - additional program headers, it will report an error `not enough + additional program headers, it will report an error 'not enough room for program headers'. To avoid this error, you must avoid - using the `SIZEOF_HEADERS' function, or you must rework your linker + using the 'SIZEOF_HEADERS' function, or you must rework your linker script to avoid forcing the linker to use additional program headers, or you must define the program headers yourself using the - `PHDRS' command (*note PHDRS::). + 'PHDRS' command (*note PHDRS::). File: ld.info, Node: Implicit Linker Scripts, Prev: Expressions, Up: Scripts @@ -4999,7 +4957,7 @@ linker will report an error. An implicit linker script will not replace the default linker script. Typically an implicit linker script would contain only symbol -assignments, or the `INPUT', `GROUP', or `VERSION' commands. +assignments, or the 'INPUT', 'GROUP', or 'VERSION' commands. Any input files read because of an implicit linker script will be read at the position in the command line where the implicit linker @@ -5011,103 +4969,90 @@ File: ld.info, Node: Machine Dependent, Next: BFD, Prev: Scripts, Up: Top 4 Machine Dependent Features **************************** -`ld' has additional features on some platforms; the following sections -describe them. Machines where `ld' has no additional functionality are +'ld' has additional features on some platforms; the following sections +describe them. Machines where 'ld' has no additional functionality are not listed. * Menu: - -* H8/300:: `ld' and the H8/300 - -* i960:: `ld' and the Intel 960 family - -* M68HC11/68HC12:: `ld' and the Motorola 68HC11 and 68HC12 families - -* ARM:: `ld' and the ARM family - -* HPPA ELF32:: `ld' and HPPA 32-bit ELF - -* M68K:: `ld' and the Motorola 68K family - -* MMIX:: `ld' and MMIX - -* MSP430:: `ld' and MSP430 - -* PowerPC ELF32:: `ld' and PowerPC 32-bit ELF Support - -* PowerPC64 ELF64:: `ld' and PowerPC64 64-bit ELF Support - -* SPU ELF:: `ld' and SPU ELF Support - -* TI COFF:: `ld' and TI COFF - -* WIN32:: `ld' and WIN32 (cygwin/mingw) - -* Xtensa:: `ld' and Xtensa Processors +* H8/300:: 'ld' and the H8/300 +* i960:: 'ld' and the Intel 960 family +* M68HC11/68HC12:: 'ld' and the Motorola 68HC11 and 68HC12 families +* ARM:: 'ld' and the ARM family +* HPPA ELF32:: 'ld' and HPPA 32-bit ELF +* M68K:: 'ld' and the Motorola 68K family +* MIPS:: 'ld' and the MIPS family +* MMIX:: 'ld' and MMIX +* MSP430:: 'ld' and MSP430 +* PowerPC ELF32:: 'ld' and PowerPC 32-bit ELF Support +* PowerPC64 ELF64:: 'ld' and PowerPC64 64-bit ELF Support +* SPU ELF:: 'ld' and SPU ELF Support +* TI COFF:: 'ld' and TI COFF +* WIN32:: 'ld' and WIN32 (cygwin/mingw) +* Xtensa:: 'ld' and Xtensa Processors File: ld.info, Node: H8/300, Next: i960, Up: Machine Dependent -4.1 `ld' and the H8/300 +4.1 'ld' and the H8/300 ======================= -For the H8/300, `ld' can perform these global optimizations when you -specify the `--relax' command-line option. +For the H8/300, 'ld' can perform these global optimizations when you +specify the '--relax' command-line option. _relaxing address modes_ - `ld' finds all `jsr' and `jmp' instructions whose targets are + 'ld' finds all 'jsr' and 'jmp' instructions whose targets are within eight bits, and turns them into eight-bit program-counter - relative `bsr' and `bra' instructions, respectively. + relative 'bsr' and 'bra' instructions, respectively. _synthesizing instructions_ - `ld' finds all `mov.b' instructions which use the sixteen-bit + 'ld' finds all 'mov.b' instructions which use the sixteen-bit absolute address form, but refer to the top page of memory, and changes them to use the eight-bit address form. (That is: the - linker turns `mov.b `@'AA:16' into `mov.b `@'AA:8' whenever the + linker turns 'mov.b '@'AA:16' into 'mov.b '@'AA:8' whenever the address AA is in the top page of memory). - `ld' finds all `mov' instructions which use the register indirect + 'ld' finds all 'mov' instructions which use the register indirect with 32-bit displacement addressing mode, but use a small displacement inside 16-bit displacement range, and changes them to use the 16-bit displacement form. (That is: the linker turns - `mov.b `@'D:32,ERx' into `mov.b `@'D:16,ERx' whenever the - displacement D is in the 16 bit signed integer range. Only + 'mov.b '@'D:32,ERx' into 'mov.b '@'D:16,ERx' whenever the + displacement D is in the 16 bit signed integer range. Only implemented in ELF-format ld). _bit manipulation instructions_ - `ld' finds all bit manipulation instructions like `band, bclr, + 'ld' finds all bit manipulation instructions like 'band, bclr, biand, bild, bior, bist, bixor, bld, bnot, bor, bset, bst, btst, bxor' which use 32 bit and 16 bit absolute address form, but refer to the top page of memory, and changes them to use the 8 bit - address form. (That is: the linker turns `bset #xx:3,`@'AA:32' - into `bset #xx:3,`@'AA:8' whenever the address AA is in the top + address form. (That is: the linker turns 'bset #xx:3,'@'AA:32' + into 'bset #xx:3,'@'AA:8' whenever the address AA is in the top page of memory). _system control instructions_ - `ld' finds all `ldc.w, stc.w' instructions which use the 32 bit + 'ld' finds all 'ldc.w, stc.w' instructions which use the 32 bit absolute address form, but refer to the top page of memory, and changes them to use 16 bit address form. (That is: the linker - turns `ldc.w `@'AA:32,ccr' into `ldc.w `@'AA:16,ccr' whenever the + turns 'ldc.w '@'AA:32,ccr' into 'ldc.w '@'AA:16,ccr' whenever the address AA is in the top page of memory). File: ld.info, Node: i960, Next: M68HC11/68HC12, Prev: H8/300, Up: Machine Dependent -4.2 `ld' and the Intel 960 Family +4.2 'ld' and the Intel 960 Family ================================= -You can use the `-AARCHITECTURE' command line option to specify one of +You can use the '-AARCHITECTURE' command line option to specify one of the two-letter names identifying members of the 960 family; the option specifies the desired output target, and warns of any incompatible instructions in the input files. It also modifies the linker's search -strategy for archive libraries, to support the use of libraries -specific to each particular architecture, by including in the search -loop names suffixed with the string identifying the architecture. +strategy for archive libraries, to support the use of libraries specific +to each particular architecture, by including in the search loop names +suffixed with the string identifying the architecture. - For example, if your `ld' command line included `-ACA' as well as -`-ltry', the linker would look (in its built-in search paths, and in -any paths you specify with `-L') for a library with the names + For example, if your 'ld' command line included '-ACA' as well as +'-ltry', the linker would look (in its built-in search paths, and in any +paths you specify with '-L') for a library with the names try libtry.a @@ -5115,134 +5060,131 @@ any paths you specify with `-L') for a library with the names libtryca.a The first two possibilities would be considered in any event; the last -two are due to the use of `-ACA'. +two are due to the use of '-ACA'. - You can meaningfully use `-A' more than once on a command line, since + You can meaningfully use '-A' more than once on a command line, since the 960 architecture family allows combination of target architectures; -each use will add another pair of name variants to search for when `-l' +each use will add another pair of name variants to search for when '-l' specifies a library. - `ld' supports the `--relax' option for the i960 family. If you -specify `--relax', `ld' finds all `balx' and `calx' instructions whose + 'ld' supports the '--relax' option for the i960 family. If you +specify '--relax', 'ld' finds all 'balx' and 'calx' instructions whose targets are within 24 bits, and turns them into 24-bit program-counter -relative `bal' and `cal' instructions, respectively. `ld' also turns -`cal' instructions into `bal' instructions when it determines that the +relative 'bal' and 'cal' instructions, respectively. 'ld' also turns +'cal' instructions into 'bal' instructions when it determines that the target subroutine is a leaf routine (that is, the target subroutine does not itself call any subroutines). - The `--fix-cortex-a8' switch enables a link-time workaround for an + The '--fix-cortex-a8' switch enables a link-time workaround for an erratum in certain Cortex-A8 processors. The workaround is enabled by default if you are targeting the ARM v7-A architecture profile. It can -be enabled otherwise by specifying `--fix-cortex-a8', or disabled -unconditionally by specifying `--no-fix-cortex-a8'. +be enabled otherwise by specifying '--fix-cortex-a8', or disabled +unconditionally by specifying '--no-fix-cortex-a8'. The erratum only affects Thumb-2 code. Please contact ARM for further details. - The `--no-merge-exidx-entries' switch disables the merging of + The '--no-merge-exidx-entries' switch disables the merging of adjacent exidx entries in debuginfo. File: ld.info, Node: M68HC11/68HC12, Next: ARM, Prev: i960, Up: Machine Dependent -4.3 `ld' and the Motorola 68HC11 and 68HC12 families +4.3 'ld' and the Motorola 68HC11 and 68HC12 families ==================================================== 4.3.1 Linker Relaxation ----------------------- -For the Motorola 68HC11, `ld' can perform these global optimizations -when you specify the `--relax' command-line option. +For the Motorola 68HC11, 'ld' can perform these global optimizations +when you specify the '--relax' command-line option. _relaxing address modes_ - `ld' finds all `jsr' and `jmp' instructions whose targets are + 'ld' finds all 'jsr' and 'jmp' instructions whose targets are within eight bits, and turns them into eight-bit program-counter - relative `bsr' and `bra' instructions, respectively. + relative 'bsr' and 'bra' instructions, respectively. - `ld' also looks at all 16-bit extended addressing modes and + 'ld' also looks at all 16-bit extended addressing modes and transforms them in a direct addressing mode when the address is in page 0 (between 0 and 0x0ff). _relaxing gcc instruction group_ - When `gcc' is called with `-mrelax', it can emit group of + When 'gcc' is called with '-mrelax', it can emit group of instructions that the linker can optimize to use a 68HC11 direct - addressing mode. These instructions consists of `bclr' or `bset' + addressing mode. These instructions consists of 'bclr' or 'bset' instructions. - 4.3.2 Trampoline Generation --------------------------- -For 68HC11 and 68HC12, `ld' can generate trampoline code to call a far -function using a normal `jsr' instruction. The linker will also change +For 68HC11 and 68HC12, 'ld' can generate trampoline code to call a far +function using a normal 'jsr' instruction. The linker will also change the relocation to some far function to use the trampoline address -instead of the function address. This is typically the case when a -pointer to a function is taken. The pointer will in fact point to the +instead of the function address. This is typically the case when a +pointer to a function is taken. The pointer will in fact point to the function trampoline. File: ld.info, Node: ARM, Next: HPPA ELF32, Prev: M68HC11/68HC12, Up: Machine Dependent -4.4 `ld' and the ARM family +4.4 'ld' and the ARM family =========================== -For the ARM, `ld' will generate code stubs to allow functions calls +For the ARM, 'ld' will generate code stubs to allow functions calls between ARM and Thumb code. These stubs only work with code that has -been compiled and assembled with the `-mthumb-interwork' command line +been compiled and assembled with the '-mthumb-interwork' command line option. If it is necessary to link with old ARM object files or libraries, which have not been compiled with the -mthumb-interwork -option then the `--support-old-code' command line switch should be -given to the linker. This will make it generate larger stub functions -which will work with non-interworking aware ARM code. Note, however, -the linker does not support generating stubs for function calls to +option then the '--support-old-code' command line switch should be given +to the linker. This will make it generate larger stub functions which +will work with non-interworking aware ARM code. Note, however, the +linker does not support generating stubs for function calls to non-interworking aware Thumb code. - The `--thumb-entry' switch is a duplicate of the generic `--entry' + The '--thumb-entry' switch is a duplicate of the generic '--entry' switch, in that it sets the program's starting address. But it also sets the bottom bit of the address, so that it can be branched to using a BX instruction, and the program will start executing in Thumb mode straight away. - The `--use-nul-prefixed-import-tables' switch is specifying, that -the import tables idata4 and idata5 have to be generated with a zero -element prefix for import libraries. This is the old style to generate -import tables. By default this option is turned off. + The '--use-nul-prefixed-import-tables' switch is specifying, that the +import tables idata4 and idata5 have to be generated with a zero element +prefix for import libraries. This is the old style to generate import +tables. By default this option is turned off. - The `--be8' switch instructs `ld' to generate BE8 format -executables. This option is only valid when linking big-endian objects. -The resulting image will contain big-endian data and little-endian code. + The '--be8' switch instructs 'ld' to generate BE8 format executables. +This option is only valid when linking big-endian objects. The +resulting image will contain big-endian data and little-endian code. - The `R_ARM_TARGET1' relocation is typically used for entries in the -`.init_array' section. It is interpreted as either `R_ARM_REL32' or -`R_ARM_ABS32', depending on the target. The `--target1-rel' and -`--target1-abs' switches override the default. + The 'R_ARM_TARGET1' relocation is typically used for entries in the +'.init_array' section. It is interpreted as either 'R_ARM_REL32' or +'R_ARM_ABS32', depending on the target. The '--target1-rel' and +'--target1-abs' switches override the default. - The `--target2=type' switch overrides the default definition of the -`R_ARM_TARGET2' relocation. Valid values for `type', their meanings, + The '--target2=type' switch overrides the default definition of the +'R_ARM_TARGET2' relocation. Valid values for 'type', their meanings, and target defaults are as follows: -`rel' - `R_ARM_REL32' (arm*-*-elf, arm*-*-eabi) - -`abs' - `R_ARM_ABS32' (arm*-*-symbianelf) - -`got-rel' - `R_ARM_GOT_PREL' (arm*-*-linux, arm*-*-*bsd) - - The `R_ARM_V4BX' relocation (defined by the ARM AAELF specification) +'rel' + 'R_ARM_REL32' (arm*-*-elf, arm*-*-eabi) +'abs' + 'R_ARM_ABS32' (arm*-*-symbianelf) +'got-rel' + 'R_ARM_GOT_PREL' (arm*-*-linux, arm*-*-*bsd) + + The 'R_ARM_V4BX' relocation (defined by the ARM AAELF specification) enables objects compiled for the ARMv4 architecture to be interworking-safe when linked with other objects compiled for ARMv4t, but also allows pure ARMv4 binaries to be built from the same ARMv4 objects. - In the latter case, the switch `--fix-v4bx' must be passed to the -linker, which causes v4t `BX rM' instructions to be rewritten as `MOV -PC,rM', since v4 processors do not have a `BX' instruction. + In the latter case, the switch '--fix-v4bx' must be passed to the +linker, which causes v4t 'BX rM' instructions to be rewritten as 'MOV +PC,rM', since v4 processors do not have a 'BX' instruction. - In the former case, the switch should not be used, and `R_ARM_V4BX' + In the former case, the switch should not be used, and 'R_ARM_V4BX' relocations are ignored. - Replace `BX rM' instructions identified by `R_ARM_V4BX' relocations + Replace 'BX rM' instructions identified by 'R_ARM_V4BX' relocations with a branch to the following veneer: TST rM, #1 @@ -5251,19 +5193,19 @@ with a branch to the following veneer: This allows generation of libraries/applications that work on ARMv4 cores and are still interworking safe. Note that the above veneer -clobbers the condition flags, so may cause incorrect program behavior -in rare cases. +clobbers the condition flags, so may cause incorrect program behavior in +rare cases. - The `--use-blx' switch enables the linker to use ARM/Thumb BLX + The '--use-blx' switch enables the linker to use ARM/Thumb BLX instructions (available on ARMv5t and above) in various situations. Currently it is used to perform calls via the PLT from Thumb code using BLX rather than using BX and a mode-switching stub before each PLT -entry. This should lead to such calls executing slightly faster. +entry. This should lead to such calls executing slightly faster. This option is enabled implicitly for SymbianOS, so there is no need to specify it if you are using that target. - The `--vfp11-denorm-fix' switch enables a link-time workaround for a + The '--vfp11-denorm-fix' switch enables a link-time workaround for a bug in certain VFP11 coprocessor hardware, which sometimes allows instructions with denorm operands (which must be handled by support code) to have those operands overwritten by subsequent instructions @@ -5272,74 +5214,74 @@ before the support code can read the intended values. The bug may be avoided in scalar mode if you allow at least one intervening instruction between a VFP11 instruction which uses a register and another instruction which writes to the same register, or -at least two intervening instructions if vector mode is in use. The bug +at least two intervening instructions if vector mode is in use. The bug only affects full-compliance floating-point mode: you do not need this -workaround if you are using "runfast" mode. Please contact ARM for +workaround if you are using "runfast" mode. Please contact ARM for further details. If you know you are using buggy VFP11 hardware, you can enable this -workaround by specifying the linker option `--vfp-denorm-fix=scalar' if -you are using the VFP11 scalar mode only, or `--vfp-denorm-fix=vector' +workaround by specifying the linker option '--vfp-denorm-fix=scalar' if +you are using the VFP11 scalar mode only, or '--vfp-denorm-fix=vector' if you are using vector mode (the latter also works for scalar code). -The default is `--vfp-denorm-fix=none'. +The default is '--vfp-denorm-fix=none'. If the workaround is enabled, instructions are scanned for -potentially-troublesome sequences, and a veneer is created for each -such sequence which may trigger the erratum. The veneer consists of the +potentially-troublesome sequences, and a veneer is created for each such +sequence which may trigger the erratum. The veneer consists of the first instruction of the sequence and a branch back to the subsequent -instruction. The original instruction is then replaced with a branch to -the veneer. The extra cycles required to call and return from the veneer -are sufficient to avoid the erratum in both the scalar and vector cases. +instruction. The original instruction is then replaced with a branch to +the veneer. The extra cycles required to call and return from the +veneer are sufficient to avoid the erratum in both the scalar and vector +cases. - The `--fix-arm1176' switch enables a link-time workaround for an + The '--fix-arm1176' switch enables a link-time workaround for an erratum in certain ARM1176 processors. The workaround is enabled by -default if you are targeting ARM v6 (excluding ARM v6T2) or earlier. -It can be disabled unconditionally by specifying `--no-fix-arm1176'. +default if you are targeting ARM v6 (excluding ARM v6T2) or earlier. It +can be disabled unconditionally by specifying '--no-fix-arm1176'. Further information is available in the "ARM1176JZ-S and ARM1176JZF-S Programmer Advice Notice" available on the ARM documentation website at: http://infocenter.arm.com/. - The `--no-enum-size-warning' switch prevents the linker from warning + The '--no-enum-size-warning' switch prevents the linker from warning when linking object files that specify incompatible EABI enumeration size attributes. For example, with this switch enabled, linking of an object file using 32-bit enumeration values with another using enumeration values fitted into the smallest possible space will not be diagnosed. - The `--no-wchar-size-warning' switch prevents the linker from -warning when linking object files that specify incompatible EABI -`wchar_t' size attributes. For example, with this switch enabled, -linking of an object file using 32-bit `wchar_t' values with another -using 16-bit `wchar_t' values will not be diagnosed. + The '--no-wchar-size-warning' switch prevents the linker from warning +when linking object files that specify incompatible EABI 'wchar_t' size +attributes. For example, with this switch enabled, linking of an object +file using 32-bit 'wchar_t' values with another using 16-bit 'wchar_t' +values will not be diagnosed. - The `--pic-veneer' switch makes the linker use PIC sequences for + The '--pic-veneer' switch makes the linker use PIC sequences for ARM/Thumb interworking veneers, even if the rest of the binary is not -PIC. This avoids problems on uClinux targets where `--emit-relocs' is +PIC. This avoids problems on uClinux targets where '--emit-relocs' is used to generate relocatable binaries. The linker will automatically generate and insert small sequences of code into a linked ARM ELF executable whenever an attempt is made to -perform a function call to a symbol that is too far away. The -placement of these sequences of instructions - called stubs - is -controlled by the command line option `--stub-group-size=N'. The -placement is important because a poor choice can create a need for -duplicate stubs, increasing the code size. The linker will try to -group stubs together in order to reduce interruptions to the flow of -code, but it needs guidance as to how big these groups should be and -where they should be placed. - - The value of `N', the parameter to the `--stub-group-size=' option +perform a function call to a symbol that is too far away. The placement +of these sequences of instructions - called stubs - is controlled by the +command line option '--stub-group-size=N'. The placement is important +because a poor choice can create a need for duplicate stubs, increasing +the code size. The linker will try to group stubs together in order to +reduce interruptions to the flow of code, but it needs guidance as to +how big these groups should be and where they should be placed. + + The value of 'N', the parameter to the '--stub-group-size=' option controls where the stub groups are placed. If it is negative then all stubs are placed after the first branch that needs them. If it is positive then the stubs can be placed either before or after the -branches that need them. If the value of `N' is 1 (either +1 or -1) +branches that need them. If the value of 'N' is 1 (either +1 or -1) then the linker will choose exactly where to place groups of stubs, -using its built in heuristics. A value of `N' greater than 1 (or +using its built in heuristics. A value of 'N' greater than 1 (or smaller than -1) tells the linker that a single group of stubs can -service at most `N' bytes from the input sections. +service at most 'N' bytes from the input sections. - The default, if `--stub-group-size=' is not specified, is `N = +1'. + The default, if '--stub-group-size=' is not specified, is 'N = +1'. Farcalls stubs insertion is fully supported for the ARM-EABI target only, because it relies on object files properties not present @@ -5348,74 +5290,87 @@ otherwise. File: ld.info, Node: HPPA ELF32, Next: M68K, Prev: ARM, Up: Machine Dependent -4.5 `ld' and HPPA 32-bit ELF Support +4.5 'ld' and HPPA 32-bit ELF Support ==================================== -When generating a shared library, `ld' will by default generate import +When generating a shared library, 'ld' will by default generate import stubs suitable for use with a single sub-space application. The -`--multi-subspace' switch causes `ld' to generate export stubs, and +'--multi-subspace' switch causes 'ld' to generate export stubs, and different (larger) import stubs suitable for use with multiple sub-spaces. - Long branch stubs and import/export stubs are placed by `ld' in stub -sections located between groups of input sections. `--stub-group-size' + Long branch stubs and import/export stubs are placed by 'ld' in stub +sections located between groups of input sections. '--stub-group-size' specifies the maximum size of a group of input sections handled by one -stub section. Since branch offsets are signed, a stub section may -serve two groups of input sections, one group before the stub section, -and one group after it. However, when using conditional branches that -require stubs, it may be better (for branch prediction) that stub -sections only serve one group of input sections. A negative value for -`N' chooses this scheme, ensuring that branches to stubs always use a -negative offset. Two special values of `N' are recognized, `1' and -`-1'. These both instruct `ld' to automatically size input section -groups for the branch types detected, with the same behaviour regarding -stub placement as other positive or negative values of `N' respectively. - - Note that `--stub-group-size' does not split input sections. A +stub section. Since branch offsets are signed, a stub section may serve +two groups of input sections, one group before the stub section, and one +group after it. However, when using conditional branches that require +stubs, it may be better (for branch prediction) that stub sections only +serve one group of input sections. A negative value for 'N' chooses +this scheme, ensuring that branches to stubs always use a negative +offset. Two special values of 'N' are recognized, '1' and '-1'. These +both instruct 'ld' to automatically size input section groups for the +branch types detected, with the same behaviour regarding stub placement +as other positive or negative values of 'N' respectively. + + Note that '--stub-group-size' does not split input sections. A single input section larger than the group size specified will of course create a larger group (of one section). If input sections are too large, it may not be possible for a branch to reach its stub. -File: ld.info, Node: M68K, Next: MMIX, Prev: HPPA ELF32, Up: Machine Dependent +File: ld.info, Node: M68K, Next: MIPS, Prev: HPPA ELF32, Up: Machine Dependent -4.6 `ld' and the Motorola 68K family +4.6 'ld' and the Motorola 68K family ==================================== -The `--got=TYPE' option lets you choose the GOT generation scheme. The -choices are `single', `negative', `multigot' and `target'. When -`target' is selected the linker chooses the default GOT generation -scheme for the current target. `single' tells the linker to generate a -single GOT with entries only at non-negative offsets. `negative' +The '--got=TYPE' option lets you choose the GOT generation scheme. The +choices are 'single', 'negative', 'multigot' and 'target'. When +'target' is selected the linker chooses the default GOT generation +scheme for the current target. 'single' tells the linker to generate a +single GOT with entries only at non-negative offsets. 'negative' instructs the linker to generate a single GOT with entries at both negative and positive offsets. Not all environments support such GOTs. -`multigot' allows the linker to generate several GOTs in the output +'multigot' allows the linker to generate several GOTs in the output file. All GOT references from a single input object file access the same GOT, but references from different input object files might access different GOTs. Not all environments support such GOTs. -File: ld.info, Node: MMIX, Next: MSP430, Prev: M68K, Up: Machine Dependent +File: ld.info, Node: MIPS, Next: MMIX, Prev: M68K, Up: Machine Dependent -4.7 `ld' and MMIX +4.7 'ld' and the MIPS family +============================ + +The '--insn32' and '--no-insn32' options control the choice of microMIPS +instructions used in code generated by the linker, such as that in the +PLT or lazy binding stubs, or in relaxation. If '--insn32' is used, +then the linker only uses 32-bit instruction encodings. By default or +if '--no-insn32' is used, all instruction encodings are used, including +16-bit ones where possible. + + +File: ld.info, Node: MMIX, Next: MSP430, Prev: MIPS, Up: Machine Dependent + +4.8 'ld' and MMIX ================= -For MMIX, there is a choice of generating `ELF' object files or `mmo' -object files when linking. The simulator `mmix' understands the `mmo' -format. The binutils `objcopy' utility can translate between the two +For MMIX, there is a choice of generating 'ELF' object files or 'mmo' +object files when linking. The simulator 'mmix' understands the 'mmo' +format. The binutils 'objcopy' utility can translate between the two formats. - There is one special section, the `.MMIX.reg_contents' section. + There is one special section, the '.MMIX.reg_contents' section. Contents in this section is assumed to correspond to that of global registers, and symbols referring to it are translated to special symbols, equal to registers. In a final link, the start address of the -`.MMIX.reg_contents' section corresponds to the first allocated global -register multiplied by 8. Register `$255' is not included in this +'.MMIX.reg_contents' section corresponds to the first allocated global +register multiplied by 8. Register '$255' is not included in this section; it is always set to the program entry, which is at the symbol -`Main' for `mmo' files. +'Main' for 'mmo' files. - Global symbols with the prefix `__.MMIX.start.', for example -`__.MMIX.start..text' and `__.MMIX.start..data' are special. The + Global symbols with the prefix '__.MMIX.start.', for example +'__.MMIX.start..text' and '__.MMIX.start..data' are special. The default linker script uses these to set the default start address of a section. @@ -5425,155 +5380,155 @@ section, are left out from an mmo file. File: ld.info, Node: MSP430, Next: PowerPC ELF32, Prev: MMIX, Up: Machine Dependent -4.8 `ld' and MSP430 +4.9 'ld' and MSP430 =================== For the MSP430 it is possible to select the MPU architecture. The flag -`-m [mpu type]' will select an appropriate linker script for selected -MPU type. (To get a list of known MPUs just pass `-m help' option to +'-m [mpu type]' will select an appropriate linker script for selected +MPU type. (To get a list of known MPUs just pass '-m help' option to the linker). The linker will recognize some extra sections which are MSP430 specific: -``.vectors'' +''.vectors'' Defines a portion of ROM where interrupt vectors located. -``.bootloader'' +''.bootloader'' Defines the bootloader portion of the ROM (if applicable). Any code in this section will be uploaded to the MPU. -``.infomem'' +''.infomem'' Defines an information memory section (if applicable). Any code in this section will be uploaded to the MPU. -``.infomemnobits'' - This is the same as the `.infomem' section except that any code in +''.infomemnobits'' + This is the same as the '.infomem' section except that any code in this section will not be uploaded to the MPU. -``.noinit'' - Denotes a portion of RAM located above `.bss' section. +''.noinit'' + Denotes a portion of RAM located above '.bss' section. The last two sections are used by gcc. File: ld.info, Node: PowerPC ELF32, Next: PowerPC64 ELF64, Prev: MSP430, Up: Machine Dependent -4.9 `ld' and PowerPC 32-bit ELF Support -======================================= +4.10 'ld' and PowerPC 32-bit ELF Support +======================================== Branches on PowerPC processors are limited to a signed 26-bit -displacement, which may result in `ld' giving `relocation truncated to -fit' errors with very large programs. `--relax' enables the generation +displacement, which may result in 'ld' giving 'relocation truncated to +fit' errors with very large programs. '--relax' enables the generation of trampolines that can access the entire 32-bit address space. These -trampolines are inserted at section boundaries, so may not themselves -be reachable if an input section exceeds 33M in size. You may combine -`-r' and `--relax' to add trampolines in a partial link. In that case -both branches to undefined symbols and inter-section branches are also +trampolines are inserted at section boundaries, so may not themselves be +reachable if an input section exceeds 33M in size. You may combine '-r' +and '--relax' to add trampolines in a partial link. In that case both +branches to undefined symbols and inter-section branches are also considered potentially out of range, and trampolines inserted. -`--bss-plt' - Current PowerPC GCC accepts a `-msecure-plt' option that generates +'--bss-plt' + Current PowerPC GCC accepts a '-msecure-plt' option that generates code capable of using a newer PLT and GOT layout that has the security advantage of no executable section ever needing to be writable and no writable section ever being executable. PowerPC - `ld' will generate this layout, including stubs to access the PLT, + 'ld' will generate this layout, including stubs to access the PLT, if all input files (including startup and static libraries) were - compiled with `-msecure-plt'. `--bss-plt' forces the old BSS PLT + compiled with '-msecure-plt'. '--bss-plt' forces the old BSS PLT (and GOT layout) which can give slightly better performance. -`--secure-plt' - `ld' will use the new PLT and GOT layout if it is linking new - `-fpic' or `-fPIC' code, but does not do so automatically when +'--secure-plt' + 'ld' will use the new PLT and GOT layout if it is linking new + '-fpic' or '-fPIC' code, but does not do so automatically when linking non-PIC code. This option requests the new PLT and GOT layout. A warning will be given if some object file requires the old style BSS PLT. -`--sdata-got' +'--sdata-got' The new secure PLT and GOT are placed differently relative to other - sections compared to older BSS PLT and GOT placement. The - location of `.plt' must change because the new secure PLT is an - initialized section while the old PLT is uninitialized. The - reason for the `.got' change is more subtle: The new placement - allows `.got' to be read-only in applications linked with `-z - relro -z now'. However, this placement means that `.sdata' cannot - always be used in shared libraries, because the PowerPC ABI - accesses `.sdata' in shared libraries from the GOT pointer. - `--sdata-got' forces the old GOT placement. PowerPC GCC doesn't - use `.sdata' in shared libraries, so this option is really only - useful for other compilers that may do so. - -`--emit-stub-syms' - This option causes `ld' to label linker stubs with a local symbol + sections compared to older BSS PLT and GOT placement. The location + of '.plt' must change because the new secure PLT is an initialized + section while the old PLT is uninitialized. The reason for the + '.got' change is more subtle: The new placement allows '.got' to be + read-only in applications linked with '-z relro -z now'. However, + this placement means that '.sdata' cannot always be used in shared + libraries, because the PowerPC ABI accesses '.sdata' in shared + libraries from the GOT pointer. '--sdata-got' forces the old GOT + placement. PowerPC GCC doesn't use '.sdata' in shared libraries, + so this option is really only useful for other compilers that may + do so. + +'--emit-stub-syms' + This option causes 'ld' to label linker stubs with a local symbol that encodes the stub type and destination. -`--no-tls-optimize' - PowerPC `ld' normally performs some optimization of code sequences +'--no-tls-optimize' + PowerPC 'ld' normally performs some optimization of code sequences used to access Thread-Local Storage. Use this option to disable the optimization. File: ld.info, Node: PowerPC64 ELF64, Next: SPU ELF, Prev: PowerPC ELF32, Up: Machine Dependent -4.10 `ld' and PowerPC64 64-bit ELF Support +4.11 'ld' and PowerPC64 64-bit ELF Support ========================================== -`--stub-group-size' - Long branch stubs, PLT call stubs and TOC adjusting stubs are - placed by `ld' in stub sections located between groups of input - sections. `--stub-group-size' specifies the maximum size of a +'--stub-group-size' + Long branch stubs, PLT call stubs and TOC adjusting stubs are + placed by 'ld' in stub sections located between groups of input + sections. '--stub-group-size' specifies the maximum size of a group of input sections handled by one stub section. Since branch offsets are signed, a stub section may serve two groups of input sections, one group before the stub section, and one group after it. However, when using conditional branches that require stubs, it may be better (for branch prediction) that stub sections only - serve one group of input sections. A negative value for `N' + serve one group of input sections. A negative value for 'N' chooses this scheme, ensuring that branches to stubs always use a - negative offset. Two special values of `N' are recognized, `1' - and `-1'. These both instruct `ld' to automatically size input - section groups for the branch types detected, with the same - behaviour regarding stub placement as other positive or negative - values of `N' respectively. + negative offset. Two special values of 'N' are recognized, '1' and + '-1'. These both instruct 'ld' to automatically size input section + groups for the branch types detected, with the same behaviour + regarding stub placement as other positive or negative values of + 'N' respectively. - Note that `--stub-group-size' does not split input sections. A + Note that '--stub-group-size' does not split input sections. A single input section larger than the group size specified will of course create a larger group (of one section). If input sections are too large, it may not be possible for a branch to reach its stub. -`--emit-stub-syms' - This option causes `ld' to label linker stubs with a local symbol +'--emit-stub-syms' + This option causes 'ld' to label linker stubs with a local symbol that encodes the stub type and destination. -`--dotsyms, --no-dotsyms' - These two options control how `ld' interprets version patterns in - a version script. Older PowerPC64 compilers emitted both a - function descriptor symbol with the same name as the function, and - a code entry symbol with the name prefixed by a dot (`.'). To - properly version a function `foo', the version script thus needs - to control both `foo' and `.foo'. The option `--dotsyms', on by - default, automatically adds the required dot-prefixed patterns. - Use `--no-dotsyms' to disable this feature. - -`--no-tls-optimize' - PowerPC64 `ld' normally performs some optimization of code +'--dotsyms, --no-dotsyms' + These two options control how 'ld' interprets version patterns in a + version script. Older PowerPC64 compilers emitted both a function + descriptor symbol with the same name as the function, and a code + entry symbol with the name prefixed by a dot ('.'). To properly + version a function 'foo', the version script thus needs to control + both 'foo' and '.foo'. The option '--dotsyms', on by default, + automatically adds the required dot-prefixed patterns. Use + '--no-dotsyms' to disable this feature. + +'--no-tls-optimize' + PowerPC64 'ld' normally performs some optimization of code sequences used to access Thread-Local Storage. Use this option to disable the optimization. -`--no-opd-optimize' - PowerPC64 `ld' normally removes `.opd' section entries +'--no-opd-optimize' + PowerPC64 'ld' normally removes '.opd' section entries corresponding to deleted link-once functions, or functions removed - by the action of `--gc-sections' or linker script `/DISCARD/'. - Use this option to disable `.opd' optimization. + by the action of '--gc-sections' or linker script '/DISCARD/'. Use + this option to disable '.opd' optimization. -`--non-overlapping-opd' +'--non-overlapping-opd' Some PowerPC64 compilers have an option to generate compressed - `.opd' entries spaced 16 bytes apart, overlapping the third word, + '.opd' entries spaced 16 bytes apart, overlapping the third word, the static chain pointer (unused in C) with the first word of the next entry. This option expands such entries to the full 24 bytes. -`--no-toc-optimize' - PowerPC64 `ld' normally removes unused `.toc' section entries. +'--no-toc-optimize' + PowerPC64 'ld' normally removes unused '.toc' section entries. Such entries are detected by examining relocations that reference the TOC in code sections. A reloc in a deleted code section marks a TOC word as unneeded, while a reloc in a kept code section marks @@ -5586,128 +5541,128 @@ File: ld.info, Node: PowerPC64 ELF64, Next: SPU ELF, Prev: PowerPC ELF32, Up assembly code is used to insert TOC entries. Use this option to disable the optimization. -`--no-multi-toc' - If given any toc option besides `-mcmodel=medium' or - `-mcmodel=large', PowerPC64 GCC generates code for a TOC model +'--no-multi-toc' + If given any toc option besides '-mcmodel=medium' or + '-mcmodel=large', PowerPC64 GCC generates code for a TOC model where TOC entries are accessed with a 16-bit offset from r2. This - limits the total TOC size to 64K. PowerPC64 `ld' extends this - limit by grouping code sections such that each group uses less - than 64K for its TOC entries, then inserts r2 adjusting stubs - between inter-group calls. `ld' does not split apart input - sections, so cannot help if a single input file has a `.toc' - section that exceeds 64K, most likely from linking multiple files - with `ld -r'. Use this option to turn off this feature. - -`--no-toc-sort' - By default, `ld' sorts TOC sections so that those whose file - happens to have a section called `.init' or `.fini' are placed + limits the total TOC size to 64K. PowerPC64 'ld' extends this limit + by grouping code sections such that each group uses less than 64K + for its TOC entries, then inserts r2 adjusting stubs between + inter-group calls. 'ld' does not split apart input sections, so + cannot help if a single input file has a '.toc' section that + exceeds 64K, most likely from linking multiple files with 'ld -r'. + Use this option to turn off this feature. + +'--no-toc-sort' + By default, 'ld' sorts TOC sections so that those whose file + happens to have a section called '.init' or '.fini' are placed first, followed by TOC sections referenced by code generated with - PowerPC64 gcc's `-mcmodel=small', and lastly TOC sections + PowerPC64 gcc's '-mcmodel=small', and lastly TOC sections referenced only by code generated with PowerPC64 gcc's - `-mcmodel=medium' or `-mcmodel=large' options. Doing this results - in better TOC grouping for multi-TOC. Use this option to turn off + '-mcmodel=medium' or '-mcmodel=large' options. Doing this results + in better TOC grouping for multi-TOC. Use this option to turn off this feature. -`--plt-align' -`--no-plt-align' +'--plt-align' +'--no-plt-align' Use these options to control whether individual PLT call stubs are aligned to a 32-byte boundary, or to the specified power of two - boundary when using `--plt-align='. By default PLT call stubs are + boundary when using '--plt-align='. By default PLT call stubs are packed tightly. -`--plt-static-chain' -`--no-plt-static-chain' +'--plt-static-chain' +'--no-plt-static-chain' Use these options to control whether PLT call stubs load the static - chain pointer (r11). `ld' defaults to not loading the static - chain since there is never any need to do so on a PLT call. + chain pointer (r11). 'ld' defaults to not loading the static chain + since there is never any need to do so on a PLT call. -`--plt-thread-safe' -`--no-thread-safe' +'--plt-thread-safe' +'--no-thread-safe' With power7's weakly ordered memory model, it is possible when using lazy binding for ld.so to update a plt entry in one thread and have another thread see the individual plt entry words update in the wrong order, despite ld.so carefully writing in the correct order and using memory write barriers. To avoid this we need some sort of read barrier in the call stub, or use LD_BIND_NOW=1. By - default, `ld' looks for calls to commonly used functions that + default, 'ld' looks for calls to commonly used functions that create threads, and if seen, adds the necessary barriers. Use these options to change the default behaviour. File: ld.info, Node: SPU ELF, Next: TI COFF, Prev: PowerPC64 ELF64, Up: Machine Dependent -4.11 `ld' and SPU ELF Support +4.12 'ld' and SPU ELF Support ============================= -`--plugin' +'--plugin' This option marks an executable as a PIC plugin module. -`--no-overlays' - Normally, `ld' recognizes calls to functions within overlay +'--no-overlays' + Normally, 'ld' recognizes calls to functions within overlay regions, and redirects such calls to an overlay manager via a stub. - `ld' also provides a built-in overlay manager. This option turns + 'ld' also provides a built-in overlay manager. This option turns off all this special overlay handling. -`--emit-stub-syms' - This option causes `ld' to label overlay stubs with a local symbol +'--emit-stub-syms' + This option causes 'ld' to label overlay stubs with a local symbol that encodes the stub type and destination. -`--extra-overlay-stubs' - This option causes `ld' to add overlay call stubs on all function +'--extra-overlay-stubs' + This option causes 'ld' to add overlay call stubs on all function calls out of overlay regions. Normally stubs are not added on calls to non-overlay regions. -`--local-store=lo:hi' - `ld' usually checks that a final executable for SPU fits in the +'--local-store=lo:hi' + 'ld' usually checks that a final executable for SPU fits in the address range 0 to 256k. This option may be used to change the - range. Disable the check entirely with `--local-store=0:0'. + range. Disable the check entirely with '--local-store=0:0'. -`--stack-analysis' +'--stack-analysis' SPU local store space is limited. Over-allocation of stack space unnecessarily limits space available for code and data, while under-allocation results in runtime failures. If given this - option, `ld' will provide an estimate of maximum stack usage. - `ld' does this by examining symbols in code sections to determine - the extents of functions, and looking at function prologues for - stack adjusting instructions. A call-graph is created by looking - for relocations on branch instructions. The graph is then searched - for the maximum stack usage path. Note that this analysis does not + option, 'ld' will provide an estimate of maximum stack usage. 'ld' + does this by examining symbols in code sections to determine the + extents of functions, and looking at function prologues for stack + adjusting instructions. A call-graph is created by looking for + relocations on branch instructions. The graph is then searched for + the maximum stack usage path. Note that this analysis does not find calls made via function pointers, and does not handle recursion and other cycles in the call graph. Stack usage may be under-estimated if your code makes such calls. Also, stack usage - for dynamic allocation, e.g. alloca, will not be detected. If a + for dynamic allocation, e.g. alloca, will not be detected. If a link map is requested, detailed information about each function's stack usage and calls will be given. -`--emit-stack-syms' - This option, if given along with `--stack-analysis' will result in - `ld' emitting stack sizing symbols for each function. These take - the form `__stack_<function_name>' for global functions, and - `__stack_<number>_<function_name>' for static functions. - `<number>' is the section id in hex. The value of such symbols is +'--emit-stack-syms' + This option, if given along with '--stack-analysis' will result in + 'ld' emitting stack sizing symbols for each function. These take + the form '__stack_<function_name>' for global functions, and + '__stack_<number>_<function_name>' for static functions. + '<number>' is the section id in hex. The value of such symbols is the stack requirement for the corresponding function. The symbol - size will be zero, type `STT_NOTYPE', binding `STB_LOCAL', and - section `SHN_ABS'. + size will be zero, type 'STT_NOTYPE', binding 'STB_LOCAL', and + section 'SHN_ABS'. File: ld.info, Node: TI COFF, Next: WIN32, Prev: SPU ELF, Up: Machine Dependent -4.12 `ld''s Support for Various TI COFF Versions +4.13 'ld''s Support for Various TI COFF Versions ================================================ -The `--format' switch allows selection of one of the various TI COFF +The '--format' switch allows selection of one of the various TI COFF versions. The latest of this writing is 2; versions 0 and 1 are also supported. The TI COFF versions also vary in header byte-order format; -`ld' will read any version or byte order, but the output header format +'ld' will read any version or byte order, but the output header format depends on the default specified by the specific target. File: ld.info, Node: WIN32, Next: Xtensa, Prev: TI COFF, Up: Machine Dependent -4.13 `ld' and WIN32 (cygwin/mingw) +4.14 'ld' and WIN32 (cygwin/mingw) ================================== -This section describes some of the win32 specific `ld' issues. See +This section describes some of the win32 specific 'ld' issues. See *note Command Line Options: Options. for detailed description of the command line options mentioned here. @@ -5715,63 +5670,58 @@ _import libraries_ The standard Windows linker creates and uses so-called import libraries, which contains information for linking to dll's. They are regular static archives and are handled as any other static - archive. The cygwin and mingw ports of `ld' have specific support - for creating such libraries provided with the `--out-implib' + archive. The cygwin and mingw ports of 'ld' have specific support + for creating such libraries provided with the '--out-implib' command line option. _exporting DLL symbols_ - The cygwin/mingw `ld' has several ways to export symbols for dll's. + The cygwin/mingw 'ld' has several ways to export symbols for dll's. - _using auto-export functionality_ - By default `ld' exports symbols with the auto-export + _using auto-export functionality_ + By default 'ld' exports symbols with the auto-export functionality, which is controlled by the following command line options: - * -export-all-symbols [This is the default] - + * -export-all-symbols [This is the default] * -exclude-symbols - * -exclude-libs - * -exclude-modules-for-implib - * -version-script - When auto-export is in operation, `ld' will export all the + When auto-export is in operation, 'ld' will export all the non-local (global and common) symbols it finds in a DLL, with - the exception of a few symbols known to belong to the - system's runtime and libraries. As it will often not be - desirable to export all of a DLL's symbols, which may include - private functions that are not part of any public interface, - the command-line options listed above may be used to filter - symbols out from the list for exporting. The `--output-def' + the exception of a few symbols known to belong to the system's + runtime and libraries. As it will often not be desirable to + export all of a DLL's symbols, which may include private + functions that are not part of any public interface, the + command-line options listed above may be used to filter + symbols out from the list for exporting. The '--output-def' option can be used in order to see the final list of exported symbols with all exclusions taken into effect. - If `--export-all-symbols' is not given explicitly on the + If '--export-all-symbols' is not given explicitly on the command line, then the default auto-export behavior will be _disabled_ if either of the following are true: * A DEF file is used. - * Any symbol in any object file was marked with the __declspec(dllexport) attribute. - _using a DEF file_ + _using a DEF file_ Another way of exporting symbols is using a DEF file. A DEF file is an ASCII file containing definitions of symbols which - should be exported when a dll is created. Usually it is - named `<dll name>.def' and is added as any other object file - to the linker's command line. The file's name must end in - `.def' or `.DEF'. + should be exported when a dll is created. Usually it is named + '<dll name>.def' and is added as any other object file to the + linker's command line. The file's name must end in '.def' or + '.DEF'. gcc -o <output> <objectfiles> <dll name>.def Using a DEF file turns off the normal auto-export behavior, - unless the `--export-all-symbols' option is also used. + unless the '--export-all-symbols' option is also used. Here is an example of a DEF file for a shared library called - `xyz.dll': + 'xyz.dll': LIBRARY "xyz.dll" BASE=0x20000000 @@ -5784,33 +5734,33 @@ _exporting DLL symbols_ doo = foo == foo2 eoo DATA == var1 - This example defines a DLL with a non-default base address - and seven symbols in the export table. The third exported - symbol `_bar' is an alias for the second. The fourth symbol, - `another_foo' is resolved by "forwarding" to another module - and treating it as an alias for `afoo' exported from the DLL - `abc.dll'. The final symbol `var1' is declared to be a data - object. The `doo' symbol in export library is an alias of - `foo', which gets the string name in export table `foo2'. The - `eoo' symbol is an data export symbol, which gets in export - table the name `var1'. - - The optional `LIBRARY <name>' command indicates the _internal_ - name of the output DLL. If `<name>' does not include a suffix, - the default library suffix, `.DLL' is appended. + This example defines a DLL with a non-default base address and + seven symbols in the export table. The third exported symbol + '_bar' is an alias for the second. The fourth symbol, + 'another_foo' is resolved by "forwarding" to another module + and treating it as an alias for 'afoo' exported from the DLL + 'abc.dll'. The final symbol 'var1' is declared to be a data + object. The 'doo' symbol in export library is an alias of + 'foo', which gets the string name in export table 'foo2'. The + 'eoo' symbol is an data export symbol, which gets in export + table the name 'var1'. + + The optional 'LIBRARY <name>' command indicates the _internal_ + name of the output DLL. If '<name>' does not include a suffix, + the default library suffix, '.DLL' is appended. When the .DEF file is used to build an application, rather - than a library, the `NAME <name>' command should be used - instead of `LIBRARY'. If `<name>' does not include a suffix, - the default executable suffix, `.EXE' is appended. + than a library, the 'NAME <name>' command should be used + instead of 'LIBRARY'. If '<name>' does not include a suffix, + the default executable suffix, '.EXE' is appended. - With either `LIBRARY <name>' or `NAME <name>' the optional - specification `BASE = <number>' may be used to specify a + With either 'LIBRARY <name>' or 'NAME <name>' the optional + specification 'BASE = <number>' may be used to specify a non-default base address for the image. - If neither `LIBRARY <name>' nor `NAME <name>' is specified, - or they specify an empty string, the internal name is the - same as the filename specified on the command line. + If neither 'LIBRARY <name>' nor 'NAME <name>' is specified, or + they specify an empty string, the internal name is the same as + the filename specified on the command line. The complete specification of an export symbol is: @@ -5819,50 +5769,50 @@ _exporting DLL symbols_ | ( <name1> = <module-name> . <external-name>)) [ @ <integer> ] [NONAME] [DATA] [CONSTANT] [PRIVATE] [== <name3>] ) * - Declares `<name1>' as an exported symbol from the DLL, or - declares `<name1>' as an exported alias for `<name2>'; or - declares `<name1>' as a "forward" alias for the symbol - `<external-name>' in the DLL `<module-name>'. Optionally, - the symbol may be exported by the specified ordinal - `<integer>' alias. The optional `<name3>' is the to be used - string in import/export table for the symbol. + Declares '<name1>' as an exported symbol from the DLL, or + declares '<name1>' as an exported alias for '<name2>'; or + declares '<name1>' as a "forward" alias for the symbol + '<external-name>' in the DLL '<module-name>'. Optionally, the + symbol may be exported by the specified ordinal '<integer>' + alias. The optional '<name3>' is the to be used string in + import/export table for the symbol. The optional keywords that follow the declaration indicate: - `NONAME': Do not put the symbol name in the DLL's export - table. It will still be exported by its ordinal alias - (either the value specified by the .def specification or, - otherwise, the value assigned by the linker). The symbol - name, however, does remain visible in the import library (if - any), unless `PRIVATE' is also specified. + 'NONAME': Do not put the symbol name in the DLL's export + table. It will still be exported by its ordinal alias (either + the value specified by the .def specification or, otherwise, + the value assigned by the linker). The symbol name, however, + does remain visible in the import library (if any), unless + 'PRIVATE' is also specified. - `DATA': The symbol is a variable or object, rather than a + 'DATA': The symbol is a variable or object, rather than a function. The import lib will export only an indirect - reference to `foo' as the symbol `_imp__foo' (ie, `foo' must - be resolved as `*_imp__foo'). + reference to 'foo' as the symbol '_imp__foo' (ie, 'foo' must + be resolved as '*_imp__foo'). - `CONSTANT': Like `DATA', but put the undecorated `foo' as - well as `_imp__foo' into the import library. Both refer to the + 'CONSTANT': Like 'DATA', but put the undecorated 'foo' as well + as '_imp__foo' into the import library. Both refer to the read-only import address table's pointer to the variable, not - to the variable itself. This can be dangerous. If the user - code fails to add the `dllimport' attribute and also fails to + to the variable itself. This can be dangerous. If the user + code fails to add the 'dllimport' attribute and also fails to explicitly add the extra indirection that the use of the attribute enforces, the application will behave unexpectedly. - `PRIVATE': Put the symbol in the DLL's export table, but do + 'PRIVATE': Put the symbol in the DLL's export table, but do not put it into the static import library used to resolve - imports at link time. The symbol can still be imported using - the `LoadLibrary/GetProcAddress' API at runtime or by by - using the GNU ld extension of linking directly to the DLL - without an import library. + imports at link time. The symbol can still be imported using + the 'LoadLibrary/GetProcAddress' API at runtime or by by using + the GNU ld extension of linking directly to the DLL without an + import library. See ld/deffilep.y in the binutils sources for the full specification of other DEF file statements - While linking a shared dll, `ld' is able to create a DEF file - with the `--output-def <file>' command line option. + While linking a shared dll, 'ld' is able to create a DEF file + with the '--output-def <file>' command line option. - _Using decorations_ + _Using decorations_ Another way of marking symbols for export is to modify the source code itself, so that when building the DLL each symbol to be exported is declared as: @@ -5870,11 +5820,10 @@ _exporting DLL symbols_ __declspec(dllexport) int a_variable __declspec(dllexport) void a_function(int with_args) - All such symbols will be exported from the DLL. If, however, + All such symbols will be exported from the DLL. If, however, any of the object files in the DLL contain symbols decorated - in this way, then the normal auto-export behavior is - disabled, unless the `--export-all-symbols' option is also - used. + in this way, then the normal auto-export behavior is disabled, + unless the '--export-all-symbols' option is also used. Note that object files that wish to access these symbols must _not_ decorate them with dllexport. Instead, they should use @@ -5889,31 +5838,31 @@ _exporting DLL symbols_ included by client code the header must declare them as dllimport. There are a number of idioms that are typically used to do this; often client code can omit the __declspec() - declaration completely. See `--enable-auto-import' and - `automatic data imports' for more information. + declaration completely. See '--enable-auto-import' and + 'automatic data imports' for more information. _automatic data imports_ The standard Windows dll format supports data imports from dlls - only by adding special decorations (dllimport/dllexport), which - let the compiler produce specific assembler instructions to deal - with this issue. This increases the effort necessary to port - existing Un*x code to these platforms, especially for large c++ - libraries and applications. The auto-import feature, which was - initially provided by Paul Sokolovsky, allows one to omit the - decorations to achieve a behavior that conforms to that on - POSIX/Un*x platforms. This feature is enabled with the - `--enable-auto-import' command-line option, although it is enabled - by default on cygwin/mingw. The `--enable-auto-import' option - itself now serves mainly to suppress any warnings that are - ordinarily emitted when linked objects trigger the feature's use. + only by adding special decorations (dllimport/dllexport), which let + the compiler produce specific assembler instructions to deal with + this issue. This increases the effort necessary to port existing + Un*x code to these platforms, especially for large c++ libraries + and applications. The auto-import feature, which was initially + provided by Paul Sokolovsky, allows one to omit the decorations to + achieve a behavior that conforms to that on POSIX/Un*x platforms. + This feature is enabled with the '--enable-auto-import' + command-line option, although it is enabled by default on + cygwin/mingw. The '--enable-auto-import' option itself now serves + mainly to suppress any warnings that are ordinarily emitted when + linked objects trigger the feature's use. auto-import of variables does not always work flawlessly without additional assistance. Sometimes, you will see this message - "variable '<var>' can't be auto-imported. Please read the - documentation for ld's `--enable-auto-import' for details." + "variable '<var>' can't be auto-imported. Please read the + documentation for ld's '--enable-auto-import' for details." - The `--enable-auto-import' documentation explains why this error + The '--enable-auto-import' documentation explains why this error occurs, and several methods that can be used to overcome this difficulty. One of these methods is the _runtime pseudo-relocs_ feature, described below. @@ -5928,38 +5877,38 @@ _automatic data imports_ standard auto-import feature described above is unable to resolve these references. - The `--enable-runtime-pseudo-relocs' switch allows these - references to be resolved without error, while leaving the task of - adjusting the references themselves (with their non-zero addends) - to specialized code provided by the runtime environment. Recent - versions of the cygwin and mingw environments and compilers - provide this runtime support; older versions do not. However, the - support is only necessary on the developer's platform; the - compiled result will run without error on an older system. + The '--enable-runtime-pseudo-relocs' switch allows these references + to be resolved without error, while leaving the task of adjusting + the references themselves (with their non-zero addends) to + specialized code provided by the runtime environment. Recent + versions of the cygwin and mingw environments and compilers provide + this runtime support; older versions do not. However, the support + is only necessary on the developer's platform; the compiled result + will run without error on an older system. - `--enable-runtime-pseudo-relocs' is not the default; it must be + '--enable-runtime-pseudo-relocs' is not the default; it must be explicitly enabled as needed. _direct linking to a dll_ - The cygwin/mingw ports of `ld' support the direct linking, + The cygwin/mingw ports of 'ld' support the direct linking, including data symbols, to a dll without the usage of any import - libraries. This is much faster and uses much less memory than - does the traditional import library method, especially when - linking large libraries or applications. When `ld' creates an - import lib, each function or variable exported from the dll is - stored in its own bfd, even though a single bfd could contain many - exports. The overhead involved in storing, loading, and - processing so many bfd's is quite large, and explains the - tremendous time, memory, and storage needed to link against - particularly large or complex libraries when using import libs. - - Linking directly to a dll uses no extra command-line switches - other than `-L' and `-l', because `ld' already searches for a - number of names to match each library. All that is needed from - the developer's perspective is an understanding of this search, in + libraries. This is much faster and uses much less memory than does + the traditional import library method, especially when linking + large libraries or applications. When 'ld' creates an import lib, + each function or variable exported from the dll is stored in its + own bfd, even though a single bfd could contain many exports. The + overhead involved in storing, loading, and processing so many bfd's + is quite large, and explains the tremendous time, memory, and + storage needed to link against particularly large or complex + libraries when using import libs. + + Linking directly to a dll uses no extra command-line switches other + than '-L' and '-l', because 'ld' already searches for a number of + names to match each library. All that is needed from the + developer's perspective is an understanding of this search, in order to force ld to select the dll instead of an import library. - For instance, when ld is called with the argument `-lxxx' it will + For instance, when ld is called with the argument '-lxxx' it will attempt to find, in the first directory of its search path, libxxx.dll.a @@ -5972,21 +5921,21 @@ _direct linking to a dll_ before moving on to the next directory in the search path. - (*) Actually, this is not `cygxxx.dll' but in fact is - `<prefix>xxx.dll', where `<prefix>' is set by the `ld' option - `--dll-search-prefix=<prefix>'. In the case of cygwin, the - standard gcc spec file includes `--dll-search-prefix=cyg', so in - effect we actually search for `cygxxx.dll'. + (*) Actually, this is not 'cygxxx.dll' but in fact is + '<prefix>xxx.dll', where '<prefix>' is set by the 'ld' option + '--dll-search-prefix=<prefix>'. In the case of cygwin, the + standard gcc spec file includes '--dll-search-prefix=cyg', so in + effect we actually search for 'cygxxx.dll'. - Other win32-based unix environments, such as mingw or pw32, may - use other `<prefix>'es, although at present only cygwin makes use - of this feature. It was originally intended to help avoid name + Other win32-based unix environments, such as mingw or pw32, may use + other '<prefix>'es, although at present only cygwin makes use of + this feature. It was originally intended to help avoid name conflicts among dll's built for the various win32/un*x environments, so that (for example) two versions of a zlib dll could coexist on the same machine. - The generic cygwin/mingw path layout uses a `bin' directory for - applications and dll's and a `lib' directory for the import + The generic cygwin/mingw path layout uses a 'bin' directory for + applications and dll's and a 'lib' directory for the import libraries (using cygwin nomenclature): bin/ @@ -5998,15 +5947,15 @@ _direct linking to a dll_ Linking directly to a dll without using the import library can be done two ways: - 1. Use the dll directly by adding the `bin' path to the link line + 1. Use the dll directly by adding the 'bin' path to the link line gcc -Wl,-verbose -o a.exe -L../bin/ -lxxx However, as the dll's often have version numbers appended to their - names (`cygncurses-5.dll') this will often fail, unless one - specifies `-L../bin -lncurses-5' to include the version. Import + names ('cygncurses-5.dll') this will often fail, unless one + specifies '-L../bin -lncurses-5' to include the version. Import libs are generally not versioned, and do not have this difficulty. - 2. Create a symbolic link from the dll to a file in the `lib' + 2. Create a symbolic link from the dll to a file in the 'lib' directory according to the above mentioned search pattern. This should be used to avoid unwanted changes in the tools needed for making the app/dll. @@ -6017,8 +5966,8 @@ _direct linking to a dll_ gcc -Wl,-verbose -o a.exe -L../lib/ -lxxx - This technique also avoids the version number problems, because - the following is perfectly legal + This technique also avoids the version number problems, because the + following is perfectly legal bin/ cygxxx-5.dll @@ -6027,22 +5976,22 @@ _direct linking to a dll_ Linking directly to a dll without using an import lib will work even when auto-import features are exercised, and even when - `--enable-runtime-pseudo-relocs' is used. + '--enable-runtime-pseudo-relocs' is used. Given the improvements in speed and memory usage, one might - justifiably wonder why import libraries are used at all. There - are three reasons: + justifiably wonder why import libraries are used at all. There are + three reasons: - 1. Until recently, the link-directly-to-dll functionality did _not_ - work with auto-imported data. + 1. Until recently, the link-directly-to-dll functionality did + _not_ work with auto-imported data. - 2. Sometimes it is necessary to include pure static objects within + 2. Sometimes it is necessary to include pure static objects within the import library (which otherwise contains only bfd's for indirection symbols that point to the exports of a dll). Again, - the import lib for the cygwin kernel makes use of this ability, - and it is not possible to do this without an import lib. + the import lib for the cygwin kernel makes use of this ability, and + it is not possible to do this without an import lib. - 3. Symbol aliases can only be resolved using an import lib. This + 3. Symbol aliases can only be resolved using an import lib. This is critical when linking against OS-supplied dll's (eg, the win32 API) in which symbols are usually exported as undecorated aliases of their stdcall-decorated assembly names. @@ -6050,17 +5999,16 @@ _direct linking to a dll_ So, import libs are not going away. But the ability to replace true import libs with a simple symbolic link to (or a copy of) a dll, in many cases, is a useful addition to the suite of tools - binutils makes available to the win32 developer. Given the - massive improvements in memory requirements during linking, storage + binutils makes available to the win32 developer. Given the massive + improvements in memory requirements during linking, storage requirements, and linking speed, we expect that many developers will soon begin to use this feature whenever possible. _symbol aliasing_ - - _adding additional names_ + _adding additional names_ Sometimes, it is useful to export symbols with additional - names. A symbol `foo' will be exported as `foo', but it can - also be exported as `_foo' by using special directives in the + names. A symbol 'foo' will be exported as 'foo', but it can + also be exported as '_foo' by using special directives in the DEF file when creating the dll. This will affect also the optional created import library. Consider the following DEF file: @@ -6071,7 +6019,7 @@ _symbol aliasing_ foo _foo = foo - The line `_foo = foo' maps the symbol `foo' to `_foo'. + The line '_foo = foo' maps the symbol 'foo' to '_foo'. Another method for creating a symbol alias is to create it in the source code using the "weak" attribute: @@ -6082,11 +6030,11 @@ _symbol aliasing_ See the gcc manual for more information about attributes and weak symbols. - _renaming symbols_ + _renaming symbols_ Sometimes it is useful to rename exports. For instance, the - cygwin kernel does this regularly. A symbol `_foo' can be - exported as `foo' but not as `_foo' by using special - directives in the DEF file. (This will also affect the import + cygwin kernel does this regularly. A symbol '_foo' can be + exported as 'foo' but not as '_foo' by using special + directives in the DEF file. (This will also affect the import library, if it is created). In the following example: LIBRARY "xyz.dll" BASE=0x61000000 @@ -6094,56 +6042,54 @@ _symbol aliasing_ EXPORTS _foo = foo - The line `_foo = foo' maps the exported symbol `foo' to - `_foo'. + The line '_foo = foo' maps the exported symbol 'foo' to + '_foo'. Note: using a DEF file disables the default auto-export behavior, - unless the `--export-all-symbols' command line option is used. - If, however, you are trying to rename symbols, then you should list + unless the '--export-all-symbols' command line option is used. If, + however, you are trying to rename symbols, then you should list _all_ desired exports in the DEF file, including the symbols that - are not being renamed, and do _not_ use the `--export-all-symbols' + are not being renamed, and do _not_ use the '--export-all-symbols' option. If you list only the renamed symbols in the DEF file, and - use `--export-all-symbols' to handle the other symbols, then the - both the new names _and_ the original names for the renamed - symbols will be exported. In effect, you'd be aliasing those - symbols, not renaming them, which is probably not what you wanted. + use '--export-all-symbols' to handle the other symbols, then the + both the new names _and_ the original names for the renamed symbols + will be exported. In effect, you'd be aliasing those symbols, not + renaming them, which is probably not what you wanted. _weak externals_ The Windows object format, PE, specifies a form of weak symbols - called weak externals. When a weak symbol is linked and the - symbol is not defined, the weak symbol becomes an alias for some - other symbol. There are three variants of weak externals: + called weak externals. When a weak symbol is linked and the symbol + is not defined, the weak symbol becomes an alias for some other + symbol. There are three variants of weak externals: * Definition is searched for in objects and libraries, historically called lazy externals. - * Definition is searched for only in other objects, not in libraries. This form is not presently implemented. - * No search; the symbol is an alias. This form is not presently implemented. As a GNU extension, weak symbols that do not specify an alternate - symbol are supported. If the symbol is undefined when linking, - the symbol uses a default value. + symbol are supported. If the symbol is undefined when linking, the + symbol uses a default value. _aligned common symbols_ - As a GNU extension to the PE file format, it is possible to - specify the desired alignment for a common symbol. This - information is conveyed from the assembler or compiler to the - linker by means of GNU-specific commands carried in the object - file's `.drectve' section, which are recognized by `ld' and - respected when laying out the common symbols. Native tools will - be able to process object files employing this GNU extension, but - will fail to respect the alignment instructions, and may issue - noisy warnings about unknown linker directives. + As a GNU extension to the PE file format, it is possible to specify + the desired alignment for a common symbol. This information is + conveyed from the assembler or compiler to the linker by means of + GNU-specific commands carried in the object file's '.drectve' + section, which are recognized by 'ld' and respected when laying out + the common symbols. Native tools will be able to process object + files employing this GNU extension, but will fail to respect the + alignment instructions, and may issue noisy warnings about unknown + linker directives. File: ld.info, Node: Xtensa, Prev: WIN32, Up: Machine Dependent -4.14 `ld' and Xtensa Processors +4.15 'ld' and Xtensa Processors =============================== -The default `ld' behavior for Xtensa processors is to interpret -`SECTIONS' commands so that lists of explicitly named sections in a +The default 'ld' behavior for Xtensa processors is to interpret +'SECTIONS' commands so that lists of explicitly named sections in a specification with a wildcard file will be interleaved when necessary to keep literal pools within the range of PC-relative load offsets. For example, with the command: @@ -6155,44 +6101,43 @@ example, with the command: } } -`ld' may interleave some of the `.literal' and `.text' sections from +'ld' may interleave some of the '.literal' and '.text' sections from different object files to ensure that the literal pools are within the -range of PC-relative load offsets. A valid interleaving might place -the `.literal' sections from an initial group of files followed by the -`.text' sections of that group of files. Then, the `.literal' sections -from the rest of the files and the `.text' sections from the rest of -the files would follow. +range of PC-relative load offsets. A valid interleaving might place the +'.literal' sections from an initial group of files followed by the +'.text' sections of that group of files. Then, the '.literal' sections +from the rest of the files and the '.text' sections from the rest of the +files would follow. - Relaxation is enabled by default for the Xtensa version of `ld' and + Relaxation is enabled by default for the Xtensa version of 'ld' and provides two important link-time optimizations. The first optimization is to combine identical literal values to reduce code size. A redundant -literal will be removed and all the `L32R' instructions that use it -will be changed to reference an identical literal, as long as the -location of the replacement literal is within the offset range of all -the `L32R' instructions. The second optimization is to remove -unnecessary overhead from assembler-generated "longcall" sequences of -`L32R'/`CALLXN' when the target functions are within range of direct -`CALLN' instructions. +literal will be removed and all the 'L32R' instructions that use it will +be changed to reference an identical literal, as long as the location of +the replacement literal is within the offset range of all the 'L32R' +instructions. The second optimization is to remove unnecessary overhead +from assembler-generated "longcall" sequences of 'L32R'/'CALLXN' when +the target functions are within range of direct 'CALLN' instructions. For each of these cases where an indirect call sequence can be -optimized to a direct call, the linker will change the `CALLXN' -instruction to a `CALLN' instruction, remove the `L32R' instruction, -and remove the literal referenced by the `L32R' instruction if it is -not used for anything else. Removing the `L32R' instruction always -reduces code size but can potentially hurt performance by changing the -alignment of subsequent branch targets. By default, the linker will -always preserve alignments, either by switching some instructions -between 24-bit encodings and the equivalent density instructions or by -inserting a no-op in place of the `L32R' instruction that was removed. -If code size is more important than performance, the `--size-opt' -option can be used to prevent the linker from widening density -instructions or inserting no-ops, except in a few cases where no-ops -are required for correctness. +optimized to a direct call, the linker will change the 'CALLXN' +instruction to a 'CALLN' instruction, remove the 'L32R' instruction, and +remove the literal referenced by the 'L32R' instruction if it is not +used for anything else. Removing the 'L32R' instruction always reduces +code size but can potentially hurt performance by changing the alignment +of subsequent branch targets. By default, the linker will always +preserve alignments, either by switching some instructions between +24-bit encodings and the equivalent density instructions or by inserting +a no-op in place of the 'L32R' instruction that was removed. If code +size is more important than performance, the '--size-opt' option can be +used to prevent the linker from widening density instructions or +inserting no-ops, except in a few cases where no-ops are required for +correctness. The following Xtensa-specific command-line options can be used to control the linker: -`--size-opt' +'--size-opt' When optimizing indirect calls to direct calls, optimize for code size more than performance. With this option, the linker will not insert no-ops or widen density instructions to preserve branch @@ -6211,22 +6156,22 @@ object files whatever the object file format. A different object file format can be supported simply by creating a new BFD back end and adding it to the library. To conserve runtime memory, however, the linker and associated tools are usually configured to support only a subset of the -object file formats available. You can use `objdump -i' (*note -objdump: (binutils.info)objdump.) to list all the formats available for -your configuration. +object file formats available. You can use 'objdump -i' (*note objdump: +(binutils.info)objdump.) to list all the formats available for your +configuration. As with most implementations, BFD is a compromise between several -conflicting requirements. The major factor influencing BFD design was -efficiency: any time used converting between formats is time which -would not have been spent had BFD not been involved. This is partly -offset by abstraction payback; since BFD simplifies applications and -back ends, more time and care may be spent optimizing algorithms for a -greater speed. +conflicting requirements. The major factor influencing BFD design was +efficiency: any time used converting between formats is time which would +not have been spent had BFD not been involved. This is partly offset by +abstraction payback; since BFD simplifies applications and back ends, +more time and care may be spent optimizing algorithms for a greater +speed. One minor artifact of the BFD solution which you should bear in mind is the potential for information loss. There are two places where useful information can be lost using the BFD mechanism: during -conversion and during output. *Note BFD information loss::. +conversion and during output. *Note BFD information loss::. * Menu: @@ -6243,18 +6188,18 @@ the format of the input object file. They then build a descriptor in memory with pointers to routines that will be used to access elements of the object file's data structures. - As different information from the object files is required, BFD -reads from different sections of the file and processes them. For -example, a very common operation for the linker is processing symbol -tables. Each BFD back end provides a routine for converting between -the object file's representation of symbols and an internal canonical -format. When the linker asks for the symbol table of an object file, it -calls through a memory pointer to the routine from the relevant BFD -back end which reads and converts the table into a canonical form. The -linker then operates upon the canonical form. When the link is finished -and the linker writes the output file's symbol table, another BFD back -end routine is called to take the newly created symbol table and -convert it into the chosen output format. + As different information from the object files is required, BFD reads +from different sections of the file and processes them. For example, a +very common operation for the linker is processing symbol tables. Each +BFD back end provides a routine for converting between the object file's +representation of symbols and an internal canonical format. When the +linker asks for the symbol table of an object file, it calls through a +memory pointer to the routine from the relevant BFD back end which reads +and converts the table into a canonical form. The linker then operates +upon the canonical form. When the link is finished and the linker +writes the output file's symbol table, another BFD back end routine is +called to take the newly created symbol table and convert it into the +chosen output format. * Menu: @@ -6267,25 +6212,25 @@ File: ld.info, Node: BFD information loss, Next: Canonical format, Up: BFD ou 5.1.1 Information Loss ---------------------- -_Information can be lost during output._ The output formats supported -by BFD do not provide identical facilities, and information which can -be described in one form has nowhere to go in another format. One -example of this is alignment information in `b.out'. There is nowhere -in an `a.out' format file to store alignment information on the -contained data, so when a file is linked from `b.out' and an `a.out' -image is produced, alignment information will not propagate to the -output file. (The linker will still use the alignment information -internally, so the link is performed correctly). - - Another example is COFF section names. COFF files may contain an -unlimited number of sections, each one with a textual section name. If +_Information can be lost during output._ The output formats supported +by BFD do not provide identical facilities, and information which can be +described in one form has nowhere to go in another format. One example +of this is alignment information in 'b.out'. There is nowhere in an +'a.out' format file to store alignment information on the contained +data, so when a file is linked from 'b.out' and an 'a.out' image is +produced, alignment information will not propagate to the output file. +(The linker will still use the alignment information internally, so the +link is performed correctly). + + Another example is COFF section names. COFF files may contain an +unlimited number of sections, each one with a textual section name. If the target of the link is a format which does not have many sections -(e.g., `a.out') or has sections without names (e.g., the Oasys format), -the link cannot be done simply. You can circumvent this problem by +(e.g., 'a.out') or has sections without names (e.g., the Oasys format), +the link cannot be done simply. You can circumvent this problem by describing the desired input-to-output section mapping with the linker command language. - _Information can be lost during canonicalization._ The BFD internal + _Information can be lost during canonicalization._ The BFD internal canonical form of the external formats is not exhaustive; there are structures in input formats for which there is no direct representation internally. This means that the BFD back ends cannot maintain all @@ -6296,16 +6241,16 @@ internal and back to external formats. format and writes another. Each BFD back end is responsible for maintaining as much data as possible, and the internal BFD canonical form has structures which are opaque to the BFD core, and exported only -to the back ends. When a file is read in one format, the canonical form -is generated for BFD and the application. At the same time, the back -end saves away any information which may otherwise be lost. If the data +to the back ends. When a file is read in one format, the canonical form +is generated for BFD and the application. At the same time, the back +end saves away any information which may otherwise be lost. If the data is then written back in the same format, the back end routine will be able to use the canonical form provided by the BFD core as well as the information it prepared earlier. Since there is a great deal of -commonality between back ends, there is no information lost when -linking or copying big endian COFF to little endian COFF, or `a.out' to -`b.out'. When a mixture of formats is linked, the information is only -lost from the files whose format differs from the destination. +commonality between back ends, there is no information lost when linking +or copying big endian COFF to little endian COFF, or 'a.out' to 'b.out'. +When a mixture of formats is linked, the information is only lost from +the files whose format differs from the destination. File: ld.info, Node: Canonical format, Prev: BFD information loss, Up: BFD outline @@ -6316,16 +6261,16 @@ File: ld.info, Node: Canonical format, Prev: BFD information loss, Up: BFD ou The greatest potential for loss of information occurs when there is the least overlap between the information provided by the source format, that stored by the canonical format, and that needed by the destination -format. A brief description of the canonical form may help you +format. A brief description of the canonical form may help you understand which kinds of data you can count on preserving across -conversions. +conversions. _files_ Information stored on a per-file basis includes target machine architecture, particular implementation format type, a demand pageable bit, and a write protected bit. Information like Unix magic numbers is not stored here--only the magic numbers' meaning, - so a `ZMAGIC' file would have both the demand pageable bit and the + so a 'ZMAGIC' file would have both the demand pageable bit and the write protected text bit set. The byte order of the target is stored on a per-file basis, so that big- and little-endian object files may be used with one another. @@ -6344,14 +6289,14 @@ _symbols_ section where they were defined. Doing this ensures that each symbol points to its containing section. Each symbol also has a varying amount of hidden private data for the BFD back end. Since - the symbol points to the original file, the private data format - for that symbol is accessible. `ld' can operate on a collection - of symbols of wildly different formats without problems. - - Normal global and simple local symbols are maintained on output, - so an output file (no matter its format) will retain symbols - pointing to functions and to global, static, and common variables. - Some symbol information is not worth retaining; in `a.out', type + the symbol points to the original file, the private data format for + that symbol is accessible. 'ld' can operate on a collection of + symbols of wildly different formats without problems. + + Normal global and simple local symbols are maintained on output, so + an output file (no matter its format) will retain symbols pointing + to functions and to global, static, and common variables. Some + symbol information is not worth retaining; in 'a.out', type information is stored in the symbol table as long symbol names. This information would be useless to most COFF debuggers; the linker has command line switches to allow users to throw it away. @@ -6359,17 +6304,17 @@ _symbols_ There is one word of type information within the symbol, so if the format supports symbol type information within symbols (for example, COFF, IEEE, Oasys) and the type is simple enough to fit - within one word (nearly everything but aggregates), the - information will be preserved. + within one word (nearly everything but aggregates), the information + will be preserved. _relocation level_ Each canonical BFD relocation record contains a pointer to the symbol to relocate to, the offset of the data to relocate, the section the data is in, and a pointer to a relocation type - descriptor. Relocation is performed by passing messages through - the relocation type descriptor and the symbol pointer. Therefore, + descriptor. Relocation is performed by passing messages through + the relocation type descriptor and the symbol pointer. Therefore, relocations can be performed on output data using a relocation - method that is only available in one of the input formats. For + method that is only available in one of the input formats. For instance, Oasys provides a byte relocation format. A relocation record requesting this relocation type would point indirectly to a routine to perform this, so the relocation may be performed on a @@ -6381,13 +6326,13 @@ _line numbers_ mapping between symbols, source line numbers, and addresses in the output file. These addresses have to be relocated along with the symbol information. Each symbol with an associated list of line - number records points to the first record of the list. The head - of a line number list consists of a pointer to the symbol, which - allows finding out the address of the function whose line number - is being described. The rest of the list is made up of pairs: - offsets into the section and line numbers. Any format which can - simply derive this information can pass it successfully between - formats (COFF, IEEE and Oasys). + number records points to the first record of the list. The head of + a line number list consists of a pointer to the symbol, which + allows finding out the address of the function whose line number is + being described. The rest of the list is made up of pairs: offsets + into the section and line numbers. Any format which can simply + derive this information can pass it successfully between formats + (COFF, IEEE and Oasys). File: ld.info, Node: Reporting Bugs, Next: MRI, Prev: BFD, Up: Top @@ -6395,12 +6340,12 @@ File: ld.info, Node: Reporting Bugs, Next: MRI, Prev: BFD, Up: Top 6 Reporting Bugs **************** -Your bug reports play an essential role in making `ld' reliable. +Your bug reports play an essential role in making 'ld' reliable. Reporting a bug may help you by bringing a solution to your problem, or it may not. But in any case the principal function of a bug report -is to help the entire community by making the next version of `ld' work -better. Bug reports are your contribution to the maintenance of `ld'. +is to help the entire community by making the next version of 'ld' work +better. Bug reports are your contribution to the maintenance of 'ld'. In order for a bug report to serve its purpose, you must include the information that enables us to fix the bug. @@ -6420,16 +6365,16 @@ If you are not sure whether you have found a bug, here are some guidelines: * If the linker gets a fatal signal, for any input whatever, that is - a `ld' bug. Reliable linkers never crash. + a 'ld' bug. Reliable linkers never crash. - * If `ld' produces an error message for valid input, that is a bug. + * If 'ld' produces an error message for valid input, that is a bug. - * If `ld' does not produce an error message for invalid input, that + * If 'ld' does not produce an error message for invalid input, that may be a bug. In the general case, the linker can not verify that object files are correct. * If you are an experienced user of linkers, your suggestions for - improvement of `ld' are welcome in any case. + improvement of 'ld' are welcome in any case. File: ld.info, Node: Bug Reporting, Prev: Bug Criteria, Up: Reporting Bugs @@ -6438,18 +6383,18 @@ File: ld.info, Node: Bug Reporting, Prev: Bug Criteria, Up: Reporting Bugs ====================== A number of companies and individuals offer support for GNU products. -If you obtained `ld' from a support organization, we recommend you +If you obtained 'ld' from a support organization, we recommend you contact that organization first. You can find contact information for many support companies and -individuals in the file `etc/SERVICE' in the GNU Emacs distribution. +individuals in the file 'etc/SERVICE' in the GNU Emacs distribution. - Otherwise, send bug reports for `ld' to -`http://www.sourceware.org/bugzilla/ and mailto:hjl.tools@gmail.com'. + Otherwise, send bug reports for 'ld' to +<http://www.sourceware.org/bugzilla/>. - The fundamental principle of reporting bugs usefully is this: -*report all the facts*. If you are not sure whether to state a fact or -leave it out, state it! + The fundamental principle of reporting bugs usefully is this: *report +all the facts*. If you are not sure whether to state a fact or leave it +out, state it! Often people omit facts because they think they know what causes the problem and assume that some details do not matter. Thus, you might @@ -6462,8 +6407,8 @@ thing despite the bug. Play it safe and give a specific, complete example. That is the easiest thing for you to do, and the most helpful. Keep in mind that the purpose of a bug report is to enable us to fix -the bug if it is new to us. Therefore, always write your bug reports -on the assumption that the bug has not been reported previously. +the bug if it is new to us. Therefore, always write your bug reports on +the assumption that the bug has not been reported previously. Sometimes people give a few sketchy facts and ask, "Does this ring a bell?" This cannot help us fix a bug, so it is basically useless. We @@ -6472,20 +6417,20 @@ might as well expedite matters by sending them to begin with. To enable us to fix the bug, you should include all these things: - * The version of `ld'. `ld' announces it if you start it with the - `--version' argument. + * The version of 'ld'. 'ld' announces it if you start it with the + '--version' argument. Without this, we will not know whether there is any point in - looking for the bug in the current version of `ld'. + looking for the bug in the current version of 'ld'. - * Any patches you may have applied to the `ld' source, including any - patches made to the `BFD' library. + * Any patches you may have applied to the 'ld' source, including any + patches made to the 'BFD' library. * The type of machine you are using, and the operating system name and version number. - * What compiler (and its version) was used to compile `ld'--e.g. - "`gcc-2.7'". + * What compiler (and its version) was used to compile 'ld'--e.g. + "'gcc-2.7'". * The command arguments you gave the linker to link your example and observe the bug. To guarantee you will not omit something @@ -6498,29 +6443,29 @@ might as well expedite matters by sending them to begin with. * A complete input file, or set of input files, that will reproduce the bug. It is generally most helpful to send the actual object files provided that they are reasonably small. Say no more than - 10K. For bigger files you can either make them available by FTP - or HTTP or else state that you are willing to send the object - file(s) to whomever requests them. (Note - your email will be - going to a mailing list, so we do not want to clog it up with - large attachments). But small attachments are best. - - If the source files were assembled using `gas' or compiled using - `gcc', then it may be OK to send the source files rather than the + 10K. For bigger files you can either make them available by FTP or + HTTP or else state that you are willing to send the object file(s) + to whomever requests them. (Note - your email will be going to a + mailing list, so we do not want to clog it up with large + attachments). But small attachments are best. + + If the source files were assembled using 'gas' or compiled using + 'gcc', then it may be OK to send the source files rather than the object files. In this case, be sure to say exactly what version of - `gas' or `gcc' was used to produce the object files. Also say how - `gas' or `gcc' were configured. + 'gas' or 'gcc' was used to produce the object files. Also say how + 'gas' or 'gcc' were configured. * A description of what behavior you observe that you believe is incorrect. For example, "It gets a fatal signal." - Of course, if the bug is that `ld' gets a fatal signal, then we + Of course, if the bug is that 'ld' gets a fatal signal, then we will certainly notice it. But if the bug is incorrect output, we might not notice unless it is glaringly wrong. You might as well not give us a chance to make a mistake. Even if the problem you experience is a fatal signal, you should still say so explicitly. Suppose something strange is going on, - such as, your copy of `ld' is out of sync, or you have encountered + such as, your copy of 'ld' is out of sync, or you have encountered a bug in the C library on your system. (This has happened!) Your copy might crash and ours would not. If you told us to expect a crash, then when ours fails to crash, we would know that the bug @@ -6528,15 +6473,15 @@ might as well expedite matters by sending them to begin with. crash, then we would not be able to draw any conclusion from our observations. - * If you wish to suggest changes to the `ld' source, send us context - diffs, as generated by `diff' with the `-u', `-c', or `-p' option. + * If you wish to suggest changes to the 'ld' source, send us context + diffs, as generated by 'diff' with the '-u', '-c', or '-p' option. Always send diffs from the old file to the new file. If you even - discuss something in the `ld' source, refer to it by context, not + discuss something in the 'ld' source, refer to it by context, not by line number. - The line numbers in our development sources will not match those - in your sources. Your line numbers would convey no useful - information to us. + The line numbers in our development sources will not match those in + your sources. Your line numbers would convey no useful information + to us. Here are some things that are not necessary: @@ -6551,8 +6496,8 @@ might as well expedite matters by sending them to begin with. debugger with breakpoints, not by pure deduction from a series of examples. We recommend that you save your time for something else. - Of course, if you can find a simpler example to report _instead_ - of the original one, that is a convenience for us. Errors in the + Of course, if you can find a simpler example to report _instead_ of + the original one, that is a convenience for us. Errors in the output will be easier to spot, running under the debugger will take less time, and so on. @@ -6564,15 +6509,15 @@ might as well expedite matters by sending them to begin with. A patch for the bug does help us if it is a good one. But do not omit the necessary information, such as the test case, on the - assumption that a patch is all we need. We might see problems - with your patch and decide to fix the problem another way, or we - might not understand it at all. + assumption that a patch is all we need. We might see problems with + your patch and decide to fix the problem another way, or we might + not understand it at all. - Sometimes with a program as complicated as `ld' it is very hard to + Sometimes with a program as complicated as 'ld' it is very hard to construct an example that will make the program follow a certain path through the code. If you do not send us the example, we will - not be able to construct one, so we will not be able to verify - that the bug is fixed. + not be able to construct one, so we will not be able to verify that + the bug is fixed. And if we cannot understand what bug you are trying to fix, or why your patch should be an improvement, we will not install it. A @@ -6589,116 +6534,115 @@ File: ld.info, Node: MRI, Next: GNU Free Documentation License, Prev: Reporti Appendix A MRI Compatible Script Files ************************************** -To aid users making the transition to GNU `ld' from the MRI linker, -`ld' can use MRI compatible linker scripts as an alternative to the -more general-purpose linker scripting language described in *note -Scripts::. MRI compatible linker scripts have a much simpler command -set than the scripting language otherwise used with `ld'. GNU `ld' -supports the most commonly used MRI linker commands; these commands are -described here. +To aid users making the transition to GNU 'ld' from the MRI linker, 'ld' +can use MRI compatible linker scripts as an alternative to the more +general-purpose linker scripting language described in *note Scripts::. +MRI compatible linker scripts have a much simpler command set than the +scripting language otherwise used with 'ld'. GNU 'ld' supports the most +commonly used MRI linker commands; these commands are described here. - In general, MRI scripts aren't of much use with the `a.out' object + In general, MRI scripts aren't of much use with the 'a.out' object file format, since it only has three sections and MRI scripts lack some features to make use of them. You can specify a file containing an MRI-compatible script using the -`-c' command-line option. +'-c' command-line option. Each command in an MRI-compatible script occupies its own line; each command line starts with the keyword that identifies the command (though blank lines are also allowed for punctuation). If a line of an -MRI-compatible script begins with an unrecognized keyword, `ld' issues -a warning message, but continues processing the script. +MRI-compatible script begins with an unrecognized keyword, 'ld' issues a +warning message, but continues processing the script. - Lines beginning with `*' are comments. + Lines beginning with '*' are comments. You can write these commands using all upper-case letters, or all -lower case; for example, `chip' is the same as `CHIP'. The following +lower case; for example, 'chip' is the same as 'CHIP'. The following list shows only the upper-case form of each command. -`ABSOLUTE SECNAME' -`ABSOLUTE SECNAME, SECNAME, ... SECNAME' - Normally, `ld' includes in the output file all sections from all - the input files. However, in an MRI-compatible script, you can - use the `ABSOLUTE' command to restrict the sections that will be - present in your output program. If the `ABSOLUTE' command is used +'ABSOLUTE SECNAME' +'ABSOLUTE SECNAME, SECNAME, ... SECNAME' + Normally, 'ld' includes in the output file all sections from all + the input files. However, in an MRI-compatible script, you can use + the 'ABSOLUTE' command to restrict the sections that will be + present in your output program. If the 'ABSOLUTE' command is used at all in a script, then only the sections named explicitly in - `ABSOLUTE' commands will appear in the linker output. You can + 'ABSOLUTE' commands will appear in the linker output. You can still use other input sections (whatever you select on the command - line, or using `LOAD') to resolve addresses in the output file. + line, or using 'LOAD') to resolve addresses in the output file. -`ALIAS OUT-SECNAME, IN-SECNAME' - Use this command to place the data from input section IN-SECNAME - in a section called OUT-SECNAME in the linker output file. +'ALIAS OUT-SECNAME, IN-SECNAME' + Use this command to place the data from input section IN-SECNAME in + a section called OUT-SECNAME in the linker output file. IN-SECNAME may be an integer. -`ALIGN SECNAME = EXPRESSION' +'ALIGN SECNAME = EXPRESSION' Align the section called SECNAME to EXPRESSION. The EXPRESSION should be a power of two. -`BASE EXPRESSION' +'BASE EXPRESSION' Use the value of EXPRESSION as the lowest address (other than absolute addresses) in the output file. -`CHIP EXPRESSION' -`CHIP EXPRESSION, EXPRESSION' +'CHIP EXPRESSION' +'CHIP EXPRESSION, EXPRESSION' This command does nothing; it is accepted only for compatibility. -`END' +'END' This command does nothing whatever; it's only accepted for compatibility. -`FORMAT OUTPUT-FORMAT' - Similar to the `OUTPUT_FORMAT' command in the more general linker +'FORMAT OUTPUT-FORMAT' + Similar to the 'OUTPUT_FORMAT' command in the more general linker language, but restricted to one of these output formats: - 1. S-records, if OUTPUT-FORMAT is `S' + 1. S-records, if OUTPUT-FORMAT is 'S' - 2. IEEE, if OUTPUT-FORMAT is `IEEE' + 2. IEEE, if OUTPUT-FORMAT is 'IEEE' - 3. COFF (the `coff-m68k' variant in BFD), if OUTPUT-FORMAT is - `COFF' + 3. COFF (the 'coff-m68k' variant in BFD), if OUTPUT-FORMAT is + 'COFF' -`LIST ANYTHING...' +'LIST ANYTHING...' Print (to the standard output file) a link map, as produced by the - `ld' command-line option `-M'. + 'ld' command-line option '-M'. - The keyword `LIST' may be followed by anything on the same line, + The keyword 'LIST' may be followed by anything on the same line, with no change in its effect. -`LOAD FILENAME' -`LOAD FILENAME, FILENAME, ... FILENAME' +'LOAD FILENAME' +'LOAD FILENAME, FILENAME, ... FILENAME' Include one or more object file FILENAME in the link; this has the - same effect as specifying FILENAME directly on the `ld' command + same effect as specifying FILENAME directly on the 'ld' command line. -`NAME OUTPUT-NAME' - OUTPUT-NAME is the name for the program produced by `ld'; the - MRI-compatible command `NAME' is equivalent to the command-line - option `-o' or the general script language command `OUTPUT'. +'NAME OUTPUT-NAME' + OUTPUT-NAME is the name for the program produced by 'ld'; the + MRI-compatible command 'NAME' is equivalent to the command-line + option '-o' or the general script language command 'OUTPUT'. -`ORDER SECNAME, SECNAME, ... SECNAME' -`ORDER SECNAME SECNAME SECNAME' - Normally, `ld' orders the sections in its output file in the order +'ORDER SECNAME, SECNAME, ... SECNAME' +'ORDER SECNAME SECNAME SECNAME' + Normally, 'ld' orders the sections in its output file in the order in which they first appear in the input files. In an MRI-compatible script, you can override this ordering with the - `ORDER' command. The sections you list with `ORDER' will appear + 'ORDER' command. The sections you list with 'ORDER' will appear first in your output file, in the order specified. -`PUBLIC NAME=EXPRESSION' -`PUBLIC NAME,EXPRESSION' -`PUBLIC NAME EXPRESSION' +'PUBLIC NAME=EXPRESSION' +'PUBLIC NAME,EXPRESSION' +'PUBLIC NAME EXPRESSION' Supply a value (EXPRESSION) for external symbol NAME used in the linker input files. -`SECT SECNAME, EXPRESSION' -`SECT SECNAME=EXPRESSION' -`SECT SECNAME EXPRESSION' - You can use any of these three forms of the `SECT' command to - specify the start address (EXPRESSION) for section SECNAME. If - you have more than one `SECT' statement for the same SECNAME, only - the _first_ sets the start address. +'SECT SECNAME, EXPRESSION' +'SECT SECNAME=EXPRESSION' +'SECT SECNAME EXPRESSION' + You can use any of these three forms of the 'SECT' command to + specify the start address (EXPRESSION) for section SECNAME. If you + have more than one 'SECT' statement for the same SECNAME, only the + _first_ sets the start address. File: ld.info, Node: GNU Free Documentation License, Next: LD Index, Prev: MRI, Up: Top @@ -6709,7 +6653,7 @@ Appendix B GNU Free Documentation License Version 1.3, 3 November 2008 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. - `http://fsf.org/' + <http://fsf.org/> Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. @@ -6734,21 +6678,21 @@ Appendix B GNU Free Documentation License free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless - of subject matter or whether it is published as a printed book. - We recommend this License principally for works whose purpose is + of subject matter or whether it is published as a printed book. We + recommend this License principally for works whose purpose is instruction or reference. 1. APPLICABILITY AND DEFINITIONS This License applies to any manual or other work, in any medium, - that contains a notice placed by the copyright holder saying it - can be distributed under the terms of this License. Such a notice + that contains a notice placed by the copyright holder saying it can + be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The "Document", below, refers to any such manual or work. Any member - of the public is a licensee, and is addressed as "you". You - accept the license if you copy, modify or distribute the work in a - way requiring permission under copyright law. + of the public is a licensee, and is addressed as "you". You accept + the license if you copy, modify or distribute the work in a way + requiring permission under copyright law. A "Modified Version" of the Document means any work containing the Document or a portion of it, either copied verbatim, or with @@ -6766,12 +6710,12 @@ Appendix B GNU Free Documentation License regarding them. The "Invariant Sections" are certain Secondary Sections whose - titles are designated, as being those of Invariant Sections, in - the notice that says that the Document is released under this - License. If a section does not fit the above definition of - Secondary then it is not allowed to be designated as Invariant. - The Document may contain zero Invariant Sections. If the Document - does not identify any Invariant Sections then there are none. + titles are designated, as being those of Invariant Sections, in the + notice that says that the Document is released under this License. + If a section does not fit the above definition of Secondary then it + is not allowed to be designated as Invariant. The Document may + contain zero Invariant Sections. If the Document does not identify + any Invariant Sections then there are none. The "Cover Texts" are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice @@ -6782,27 +6726,27 @@ Appendix B GNU Free Documentation License A "Transparent" copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document - straightforwardly with generic text editors or (for images - composed of pixels) generic paint programs or (for drawings) some - widely available drawing editor, and that is suitable for input to - text formatters or for automatic translation to a variety of - formats suitable for input to text formatters. A copy made in an - otherwise Transparent file format whose markup, or absence of - markup, has been arranged to thwart or discourage subsequent - modification by readers is not Transparent. An image format is - not Transparent if used for any substantial amount of text. A - copy that is not "Transparent" is called "Opaque". + straightforwardly with generic text editors or (for images composed + of pixels) generic paint programs or (for drawings) some widely + available drawing editor, and that is suitable for input to text + formatters or for automatic translation to a variety of formats + suitable for input to text formatters. A copy made in an otherwise + Transparent file format whose markup, or absence of markup, has + been arranged to thwart or discourage subsequent modification by + readers is not Transparent. An image format is not Transparent if + used for any substantial amount of text. A copy that is not + "Transparent" is called "Opaque". Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, - SGML or XML using a publicly available DTD, and - standard-conforming simple HTML, PostScript or PDF designed for - human modification. Examples of transparent image formats include - PNG, XCF and JPG. Opaque formats include proprietary formats that - can be read and edited only by proprietary word processors, SGML or - XML for which the DTD and/or processing tools are not generally - available, and the machine-generated HTML, PostScript or PDF - produced by some word processors for output purposes only. + SGML or XML using a publicly available DTD, and standard-conforming + simple HTML, PostScript or PDF designed for human modification. + Examples of transparent image formats include PNG, XCF and JPG. + Opaque formats include proprietary formats that can be read and + edited only by proprietary word processors, SGML or XML for which + the DTD and/or processing tools are not generally available, and + the machine-generated HTML, PostScript or PDF produced by some word + processors for output purposes only. The "Title Page" means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the @@ -6840,8 +6784,8 @@ Appendix B GNU Free Documentation License may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you - distribute a large enough number of copies you must also follow - the conditions in section 3. + distribute a large enough number of copies you must also follow the + conditions in section 3. You may also lend copies, under the same conditions stated above, and you may publicly display copies. @@ -6855,12 +6799,11 @@ Appendix B GNU Free Documentation License these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The - front cover must present the full title with all words of the - title equally prominent and visible. You may add other material - on the covers in addition. Copying with changes limited to the - covers, as long as they preserve the title of the Document and - satisfy these conditions, can be treated as verbatim copying in - other respects. + front cover must present the full title with all words of the title + equally prominent and visible. You may add other material on the + covers in addition. Copying with changes limited to the covers, as + long as they preserve the title of the Document and satisfy these + conditions, can be treated as verbatim copying in other respects. If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit @@ -6868,40 +6811,39 @@ Appendix B GNU Free Documentation License adjacent pages. If you publish or distribute Opaque copies of the Document - numbering more than 100, you must either include a - machine-readable Transparent copy along with each Opaque copy, or - state in or with each Opaque copy a computer-network location from - which the general network-using public has access to download - using public-standard network protocols a complete Transparent - copy of the Document, free of added material. If you use the - latter option, you must take reasonably prudent steps, when you - begin distribution of Opaque copies in quantity, to ensure that - this Transparent copy will remain thus accessible at the stated - location until at least one year after the last time you - distribute an Opaque copy (directly or through your agents or - retailers) of that edition to the public. + numbering more than 100, you must either include a machine-readable + Transparent copy along with each Opaque copy, or state in or with + each Opaque copy a computer-network location from which the general + network-using public has access to download using public-standard + network protocols a complete Transparent copy of the Document, free + of added material. If you use the latter option, you must take + reasonably prudent steps, when you begin distribution of Opaque + copies in quantity, to ensure that this Transparent copy will + remain thus accessible at the stated location until at least one + year after the last time you distribute an Opaque copy (directly or + through your agents or retailers) of that edition to the public. It is requested, but not required, that you contact the authors of - the Document well before redistributing any large number of - copies, to give them a chance to provide you with an updated - version of the Document. + the Document well before redistributing any large number of copies, + to give them a chance to provide you with an updated version of the + Document. 4. MODIFICATIONS You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you - release the Modified Version under precisely this License, with - the Modified Version filling the role of the Document, thus - licensing distribution and modification of the Modified Version to - whoever possesses a copy of it. In addition, you must do these - things in the Modified Version: + release the Modified Version under precisely this License, with the + Modified Version filling the role of the Document, thus licensing + distribution and modification of the Modified Version to whoever + possesses a copy of it. In addition, you must do these things in + the Modified Version: A. Use in the Title Page (and on the covers, if any) a title - distinct from that of the Document, and from those of - previous versions (which should, if there were any, be listed - in the History section of the Document). You may use the - same title as a previous version if the original publisher of - that version gives permission. + distinct from that of the Document, and from those of previous + versions (which should, if there were any, be listed in the + History section of the Document). You may use the same title + as a previous version if the original publisher of that + version gives permission. B. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in @@ -6931,31 +6873,30 @@ Appendix B GNU Free Documentation License I. Preserve the section Entitled "History", Preserve its Title, and add to it an item stating at least the title, year, new - authors, and publisher of the Modified Version as given on - the Title Page. If there is no section Entitled "History" in - the Document, create one stating the title, year, authors, - and publisher of the Document as given on its Title Page, - then add an item describing the Modified Version as stated in - the previous sentence. + authors, and publisher of the Modified Version as given on the + Title Page. If there is no section Entitled "History" in the + Document, create one stating the title, year, authors, and + publisher of the Document as given on its Title Page, then add + an item describing the Modified Version as stated in the + previous sentence. J. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for - previous versions it was based on. These may be placed in - the "History" section. You may omit a network location for a - work that was published at least four years before the - Document itself, or if the original publisher of the version - it refers to gives permission. + previous versions it was based on. These may be placed in the + "History" section. You may omit a network location for a work + that was published at least four years before the Document + itself, or if the original publisher of the version it refers + to gives permission. K. For any section Entitled "Acknowledgements" or "Dedications", - Preserve the Title of the section, and preserve in the - section all the substance and tone of each of the contributor + Preserve the Title of the section, and preserve in the section + all the substance and tone of each of the contributor acknowledgements and/or dedications given therein. - L. Preserve all the Invariant Sections of the Document, - unaltered in their text and in their titles. Section numbers - or the equivalent are not considered part of the section - titles. + L. Preserve all the Invariant Sections of the Document, unaltered + in their text and in their titles. Section numbers or the + equivalent are not considered part of the section titles. M. Delete any section Entitled "Endorsements". Such a section may not be included in the Modified Version. @@ -6968,11 +6909,11 @@ Appendix B GNU Free Documentation License If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no - material copied from the Document, you may at your option - designate some or all of these sections as invariant. To do this, - add their titles to the list of Invariant Sections in the Modified - Version's license notice. These titles must be distinct from any - other section titles. + material copied from the Document, you may at your option designate + some or all of these sections as invariant. To do this, add their + titles to the list of Invariant Sections in the Modified Version's + license notice. These titles must be distinct from any other + section titles. You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various @@ -6981,15 +6922,15 @@ Appendix B GNU Free Documentation License definition of a standard. You may add a passage of up to five words as a Front-Cover Text, - and a passage of up to 25 words as a Back-Cover Text, to the end - of the list of Cover Texts in the Modified Version. Only one - passage of Front-Cover Text and one of Back-Cover Text may be - added by (or through arrangements made by) any one entity. If the - Document already includes a cover text for the same cover, - previously added by you or by arrangement made by the same entity - you are acting on behalf of, you may not add another; but you may - replace the old one, on explicit permission from the previous - publisher that added the old one. + and a passage of up to 25 words as a Back-Cover Text, to the end of + the list of Cover Texts in the Modified Version. Only one passage + of Front-Cover Text and one of Back-Cover Text may be added by (or + through arrangements made by) any one entity. If the Document + already includes a cover text for the same cover, previously added + by you or by arrangement made by the same entity you are acting on + behalf of, you may not add another; but you may replace the old + one, on explicit permission from the previous publisher that added + the old one. The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to @@ -6999,8 +6940,8 @@ Appendix B GNU Free Documentation License You may combine the Document with other documents released under this License, under the terms defined in section 4 above for - modified versions, provided that you include in the combination - all of the Invariant Sections of all of the original documents, + modified versions, provided that you include in the combination all + of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers. @@ -7027,20 +6968,20 @@ Appendix B GNU Free Documentation License documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the - rules of this License for verbatim copying of each of the - documents in all other respects. + rules of this License for verbatim copying of each of the documents + in all other respects. You may extract a single document from such a collection, and distribute it individually under this License, provided you insert - a copy of this License into the extracted document, and follow - this License in all other respects regarding verbatim copying of - that document. + a copy of this License into the extracted document, and follow this + License in all other respects regarding verbatim copying of that + document. 7. AGGREGATION WITH INDEPENDENT WORKS A compilation of the Document or its derivatives with other - separate and independent documents or works, in or on a volume of - a storage or distribution medium, is called an "aggregate" if the + separate and independent documents or works, in or on a volume of a + storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. When the Document is included in an aggregate, this @@ -7085,8 +7026,8 @@ Appendix B GNU Free Documentation License However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) - provisionally, unless and until the copyright holder explicitly - and finally terminates your license, and (b) permanently, if the + provisionally, unless and until the copyright holder explicitly and + finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation. @@ -7098,33 +7039,33 @@ Appendix B GNU Free Documentation License after your receipt of the notice. Termination of your rights under this section does not terminate - the licenses of parties who have received copies or rights from - you under this License. If your rights have been terminated and - not permanently reinstated, receipt of a copy of some or all of - the same material does not give you any rights to use it. + the licenses of parties who have received copies or rights from you + under this License. If your rights have been terminated and not + permanently reinstated, receipt of a copy of some or all of the + same material does not give you any rights to use it. - 10. FUTURE REVISIONS OF THIS LICENSE + 10. FUTURE REVISIONS OF THIS LICENSE The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See - `http://www.gnu.org/copyleft/'. + <http://www.gnu.org/copyleft/>. Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been - published (not as a draft) by the Free Software Foundation. If - the Document does not specify a version number of this License, - you may choose any version ever published (not as a draft) by the - Free Software Foundation. If the Document specifies that a proxy - can decide which future versions of this License can be used, that + published (not as a draft) by the Free Software Foundation. If the + Document does not specify a version number of this License, you may + choose any version ever published (not as a draft) by the Free + Software Foundation. If the Document specifies that a proxy can + decide which future versions of this License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Document. - 11. RELICENSING + 11. RELICENSING "Massive Multiauthor Collaboration Site" (or "MMC Site") means any World Wide Web server that publishes copyrightable works and also @@ -7154,7 +7095,6 @@ Appendix B GNU Free Documentation License site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing. - ADDENDUM: How to use this License for your documents ==================================================== @@ -7171,7 +7111,7 @@ notices just after the title page: Free Documentation License''. If you have Invariant Sections, Front-Cover Texts and Back-Cover -Texts, replace the "with...Texts." line with this: +Texts, replace the "with...Texts." line with this: with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts @@ -7182,9 +7122,9 @@ combination of the three, merge those two alternatives to suit the situation. If your document contains nontrivial examples of program code, we -recommend releasing these examples in parallel under your choice of -free software license, such as the GNU General Public License, to -permit their use in free software. +recommend releasing these examples in parallel under your choice of free +software license, such as the GNU General Public License, to permit +their use in free software. File: ld.info, Node: LD Index, Prev: GNU Free Documentation License, Up: Top @@ -7196,302 +7136,308 @@ LD Index * Menu: * ": Symbols. (line 6) -* -(: Options. (line 710) -* --accept-unknown-input-arch: Options. (line 728) -* --add-needed: Options. (line 755) -* --add-stdcall-alias: Options. (line 1612) -* --allow-multiple-definition: Options. (line 1006) -* --allow-shlib-undefined: Options. (line 1012) -* --architecture=ARCH: Options. (line 123) -* --as-needed: Options. (line 738) -* --audit AUDITLIB: Options. (line 112) -* --auxiliary=NAME: Options. (line 255) -* --bank-window: Options. (line 2044) -* --base-file: Options. (line 1617) +* -(: Options. (line 699) +* --accept-unknown-input-arch: Options. (line 717) +* --add-needed: Options. (line 744) +* --add-stdcall-alias: Options. (line 1591) +* --allow-multiple-definition: Options. (line 995) +* --allow-shlib-undefined: Options. (line 1001) +* --architecture=ARCH: Options. (line 122) +* --as-needed: Options. (line 727) +* --audit AUDITLIB: Options. (line 111) +* --auxiliary=NAME: Options. (line 254) +* --bank-window: Options. (line 2031) +* --base-file: Options. (line 1596) * --be8: ARM. (line 28) * --bss-plt: PowerPC ELF32. (line 16) -* --build-id: Options. (line 1574) -* --build-id=STYLE: Options. (line 1574) -* --check-sections: Options. (line 834) -* --copy-dt-needed-entries: Options. (line 846) -* --cref: Options. (line 866) -* --default-imported-symver: Options. (line 1049) -* --default-script=SCRIPT: Options. (line 541) -* --default-symver: Options. (line 1045) -* --defsym=SYMBOL=EXP: Options. (line 894) -* --demangle[=STYLE]: Options. (line 907) -* --depaudit AUDITLIB: Options. (line 177) -* --disable-auto-image-base: Options. (line 1796) -* --disable-auto-import: Options. (line 1931) -* --disable-long-section-names: Options. (line 1627) -* --disable-new-dtags: Options. (line 1536) -* --disable-runtime-pseudo-reloc: Options. (line 1944) -* --disable-stdcall-fixup: Options. (line 1649) -* --discard-all: Options. (line 587) -* --discard-locals: Options. (line 591) -* --dll: Options. (line 1622) -* --dll-search-prefix: Options. (line 1802) +* --build-id: Options. (line 1553) +* --build-id=STYLE: Options. (line 1553) +* --check-sections: Options. (line 822) +* --copy-dt-needed-entries: Options. (line 834) +* --cref: Options. (line 854) +* --default-imported-symver: Options. (line 1037) +* --default-script=SCRIPT: Options. (line 534) +* --default-symver: Options. (line 1033) +* --defsym=SYMBOL=EXP: Options. (line 883) +* --demangle[=STYLE]: Options. (line 896) +* --depaudit AUDITLIB: Options. (line 176) +* --disable-auto-image-base: Options. (line 1780) +* --disable-auto-import: Options. (line 1914) +* --disable-large-address-aware: Options. (line 1721) +* --disable-long-section-names: Options. (line 1606) +* --disable-new-dtags: Options. (line 1515) +* --disable-runtime-pseudo-reloc: Options. (line 1927) +* --disable-stdcall-fixup: Options. (line 1628) +* --discard-all: Options. (line 580) +* --discard-locals: Options. (line 584) +* --dll: Options. (line 1601) +* --dll-search-prefix: Options. (line 1786) * --dotsyms: PowerPC64 ELF64. (line 33) -* --dsbt-index: Options. (line 2021) -* --dsbt-size: Options. (line 2016) -* --dynamic-linker=FILE: Options. (line 920) -* --dynamic-list-cpp-new: Options. (line 826) -* --dynamic-list-cpp-typeinfo: Options. (line 830) -* --dynamic-list-data: Options. (line 823) -* --dynamic-list=DYNAMIC-LIST-FILE: Options. (line 810) -* --dynamicbase: Options. (line 1980) -* --eh-frame-hdr: Options. (line 1527) -* --emit-relocs: Options. (line 476) +* --dsbt-index: Options. (line 2009) +* --dsbt-size: Options. (line 2004) +* --dynamic-linker=FILE: Options. (line 909) +* --dynamic-list-cpp-new: Options. (line 814) +* --dynamic-list-cpp-typeinfo: Options. (line 818) +* --dynamic-list-data: Options. (line 811) +* --dynamic-list=DYNAMIC-LIST-FILE: Options. (line 798) +* --dynamicbase: Options. (line 1963) +* --eh-frame-hdr: Options. (line 1506) +* --emit-relocs: Options. (line 470) * --emit-stack-syms: SPU ELF. (line 46) -* --emit-stub-syms <1>: SPU ELF. (line 15) -* --emit-stub-syms <2>: PowerPC64 ELF64. (line 29) * --emit-stub-syms: PowerPC ELF32. (line 47) -* --enable-auto-image-base: Options. (line 1788) -* --enable-auto-import: Options. (line 1811) -* --enable-extra-pe-debug: Options. (line 1949) -* --enable-long-section-names: Options. (line 1627) -* --enable-new-dtags: Options. (line 1536) -* --enable-runtime-pseudo-reloc: Options. (line 1936) -* --enable-stdcall-fixup: Options. (line 1649) -* --entry=ENTRY: Options. (line 187) -* --error-unresolved-symbols: Options. (line 1480) -* --exclude-all-symbols: Options. (line 1703) -* --exclude-libs: Options. (line 197) -* --exclude-modules-for-implib: Options. (line 208) -* --exclude-symbols: Options. (line 1697) -* --export-all-symbols: Options. (line 1673) -* --export-dynamic: Options. (line 221) +* --emit-stub-syms <1>: PowerPC64 ELF64. (line 29) +* --emit-stub-syms <2>: SPU ELF. (line 15) +* --enable-auto-image-base: Options. (line 1772) +* --enable-auto-import: Options. (line 1795) +* --enable-extra-pe-debug: Options. (line 1932) +* --enable-long-section-names: Options. (line 1606) +* --enable-new-dtags: Options. (line 1515) +* --enable-runtime-pseudo-reloc: Options. (line 1919) +* --enable-stdcall-fixup: Options. (line 1628) +* --entry=ENTRY: Options. (line 186) +* --error-unresolved-symbols: Options. (line 1459) +* --exclude-all-symbols: Options. (line 1681) +* --exclude-libs: Options. (line 196) +* --exclude-modules-for-implib: Options. (line 207) +* --exclude-symbols: Options. (line 1675) +* --export-all-symbols: Options. (line 1651) +* --export-dynamic: Options. (line 220) * --extra-overlay-stubs: SPU ELF. (line 19) -* --fatal-warnings: Options. (line 927) -* --file-alignment: Options. (line 1707) -* --filter=NAME: Options. (line 276) -* --fix-arm1176: ARM. (line 111) -* --fix-cortex-a8: i960. (line 39) -* --fix-v4bx: ARM. (line 49) -* --fix-v4bx-interworking: ARM. (line 62) -* --force-dynamic: Options. (line 485) -* --force-exe-suffix: Options. (line 932) -* --forceinteg: Options. (line 1985) -* --format=FORMAT: Options. (line 134) +* --fatal-warnings: Options. (line 916) +* --file-alignment: Options. (line 1685) +* --filter=NAME: Options. (line 275) +* --fix-arm1176: ARM. (line 110) +* --fix-cortex-a8: i960. (line 40) +* --fix-v4bx: ARM. (line 47) +* --fix-v4bx-interworking: ARM. (line 60) +* --force-dynamic: Options. (line 479) +* --force-exe-suffix: Options. (line 921) +* --forceinteg: Options. (line 1968) +* --format=FORMAT: Options. (line 133) * --format=VERSION: TI COFF. (line 6) -* --gc-sections: Options. (line 942) -* --got: Options. (line 2057) +* --gc-sections: Options. (line 931) +* --got: Options. (line 2043) * --got=TYPE: M68K. (line 6) -* --gpsize=VALUE: Options. (line 309) -* --hash-size=NUMBER: Options. (line 1546) -* --hash-style=STYLE: Options. (line 1554) -* --heap: Options. (line 1713) -* --help: Options. (line 979) -* --image-base: Options. (line 1720) -* --just-symbols=FILE: Options. (line 508) -* --kill-at: Options. (line 1729) -* --large-address-aware: Options. (line 1734) -* --ld-generated-unwind-info: Options. (line 1531) -* --leading-underscore: Options. (line 1667) -* --library-path=DIR: Options. (line 368) -* --library=NAMESPEC: Options. (line 335) +* --gpsize=VALUE: Options. (line 307) +* --hash-size=NUMBER: Options. (line 1525) +* --hash-style=STYLE: Options. (line 1533) +* --heap: Options. (line 1691) +* --help: Options. (line 968) +* --image-base: Options. (line 1698) +* --insert-timestamp: Options. (line 1991) +* --insn32: Options. (line 2054) +* --insn32 <1>: MIPS. (line 6) +* --just-symbols=FILE: Options. (line 501) +* --kill-at: Options. (line 1707) +* --large-address-aware: Options. (line 1712) +* --ld-generated-unwind-info: Options. (line 1510) +* --leading-underscore: Options. (line 1645) +* --library-path=DIR: Options. (line 365) +* --library=NAMESPEC: Options. (line 332) * --local-store=lo:hi: SPU ELF. (line 24) -* --major-image-version: Options. (line 1743) -* --major-os-version: Options. (line 1748) -* --major-subsystem-version: Options. (line 1752) -* --merge-exidx-entries: i960. (line 48) -* --minor-image-version: Options. (line 1757) -* --minor-os-version: Options. (line 1762) -* --minor-subsystem-version: Options. (line 1766) -* --mri-script=MRI-CMDFILE: Options. (line 158) +* --major-image-version: Options. (line 1728) +* --major-os-version: Options. (line 1733) +* --major-subsystem-version: Options. (line 1737) +* --merge-exidx-entries: i960. (line 49) +* --minor-image-version: Options. (line 1742) +* --minor-os-version: Options. (line 1747) +* --minor-subsystem-version: Options. (line 1751) +* --mri-script=MRI-CMDFILE: Options. (line 157) * --multi-subspace: HPPA ELF32. (line 6) -* --nmagic: Options. (line 439) -* --no-accept-unknown-input-arch: Options. (line 728) -* --no-add-needed: Options. (line 755) -* --no-allow-shlib-undefined: Options. (line 1012) -* --no-as-needed: Options. (line 738) -* --no-bind: Options. (line 1999) -* --no-check-sections: Options. (line 834) -* --no-copy-dt-needed-entries: Options. (line 846) -* --no-define-common: Options. (line 878) -* --no-demangle: Options. (line 907) +* --nmagic: Options. (line 433) +* --no-accept-unknown-input-arch: Options. (line 717) +* --no-add-needed: Options. (line 744) +* --no-allow-shlib-undefined: Options. (line 1001) +* --no-as-needed: Options. (line 727) +* --no-bind: Options. (line 1982) +* --no-check-sections: Options. (line 822) +* --no-copy-dt-needed-entries: Options. (line 834) +* --no-define-common: Options. (line 867) +* --no-demangle: Options. (line 896) * --no-dotsyms: PowerPC64 ELF64. (line 33) -* --no-enum-size-warning: ARM. (line 120) -* --no-export-dynamic: Options. (line 221) -* --no-fatal-warnings: Options. (line 927) -* --no-fix-arm1176: ARM. (line 111) -* --no-fix-cortex-a8: i960. (line 39) -* --no-gc-sections: Options. (line 942) -* --no-isolation: Options. (line 1992) -* --no-keep-memory: Options. (line 991) -* --no-leading-underscore: Options. (line 1667) -* --no-merge-exidx-entries <1>: i960. (line 48) -* --no-merge-exidx-entries: Options. (line 2028) +* --no-enum-size-warning: ARM. (line 119) +* --no-export-dynamic: Options. (line 220) +* --no-fatal-warnings: Options. (line 916) +* --no-fix-arm1176: ARM. (line 110) +* --no-fix-cortex-a8: i960. (line 40) +* --no-gc-sections: Options. (line 931) +* --no-insn32: Options. (line 2055) +* --no-insn32 <1>: MIPS. (line 6) +* --no-isolation: Options. (line 1975) +* --no-keep-memory: Options. (line 980) +* --no-leading-underscore: Options. (line 1645) +* --no-merge-exidx-entries: Options. (line 2016) +* --no-merge-exidx-entries <1>: i960. (line 49) * --no-multi-toc: PowerPC64 ELF64. (line 74) -* --no-omagic: Options. (line 454) +* --no-omagic: Options. (line 448) * --no-opd-optimize: PowerPC64 ELF64. (line 48) * --no-overlays: SPU ELF. (line 9) * --no-plt-align: PowerPC64 ELF64. (line 96) * --no-plt-static-chain: PowerPC64 ELF64. (line 103) * --no-plt-thread-safe: PowerPC64 ELF64. (line 109) -* --no-print-gc-sections: Options. (line 964) -* --no-seh: Options. (line 1995) -* --no-tls-optimize <1>: PowerPC64 ELF64. (line 43) +* --no-print-gc-sections: Options. (line 953) +* --no-seh: Options. (line 1978) * --no-tls-optimize: PowerPC ELF32. (line 51) +* --no-tls-optimize <1>: PowerPC64 ELF64. (line 43) * --no-toc-optimize: PowerPC64 ELF64. (line 60) * --no-toc-sort: PowerPC64 ELF64. (line 86) -* --no-trampoline: Options. (line 2038) -* --no-undefined: Options. (line 998) -* --no-undefined-version: Options. (line 1040) -* --no-warn-mismatch: Options. (line 1053) -* --no-warn-search-mismatch: Options. (line 1062) -* --no-wchar-size-warning: ARM. (line 127) -* --no-whole-archive: Options. (line 1066) -* --noinhibit-exec: Options. (line 1070) +* --no-trampoline: Options. (line 2025) +* --no-undefined: Options. (line 987) +* --no-undefined-version: Options. (line 1028) +* --no-warn-mismatch: Options. (line 1041) +* --no-warn-search-mismatch: Options. (line 1050) +* --no-wchar-size-warning: ARM. (line 126) +* --no-whole-archive: Options. (line 1054) +* --noinhibit-exec: Options. (line 1058) * --non-overlapping-opd: PowerPC64 ELF64. (line 54) -* --nxcompat: Options. (line 1988) -* --oformat=OUTPUT-FORMAT: Options. (line 1082) -* --omagic: Options. (line 445) -* --out-implib: Options. (line 1779) -* --output-def: Options. (line 1771) -* --output=OUTPUT: Options. (line 460) -* --pic-executable: Options. (line 1095) -* --pic-veneer: ARM. (line 133) +* --nxcompat: Options. (line 1971) +* --oformat=OUTPUT-FORMAT: Options. (line 1069) +* --omagic: Options. (line 439) +* --out-implib: Options. (line 1764) +* --output-def: Options. (line 1756) +* --output=OUTPUT: Options. (line 454) +* --pic-executable: Options. (line 1082) +* --pic-veneer: ARM. (line 132) * --plt-align: PowerPC64 ELF64. (line 96) * --plt-static-chain: PowerPC64 ELF64. (line 103) * --plt-thread-safe: PowerPC64 ELF64. (line 109) * --plugin: SPU ELF. (line 6) -* --print-gc-sections: Options. (line 964) -* --print-map: Options. (line 402) -* --print-output-format: Options. (line 973) -* --reduce-memory-overheads: Options. (line 1560) -* --relax: Options. (line 1111) -* --relax on i960: i960. (line 31) +* --print-gc-sections: Options. (line 953) +* --print-map: Options. (line 399) +* --print-output-format: Options. (line 962) +* --reduce-memory-overheads: Options. (line 1539) +* --relax: Options. (line 1098) +* '--relax' on i960: i960. (line 32) * --relax on PowerPC: PowerPC ELF32. (line 6) -* --relax on Xtensa: Xtensa. (line 27) -* --relocatable: Options. (line 489) -* --retain-symbols-file=FILENAME: Options. (line 1137) -* --script=SCRIPT: Options. (line 532) +* '--relax' on Xtensa: Xtensa. (line 27) +* --relocatable: Options. (line 483) +* --retain-symbols-file=FILENAME: Options. (line 1124) +* --script=SCRIPT: Options. (line 525) * --sdata-got: PowerPC ELF32. (line 33) -* --section-alignment: Options. (line 1954) -* --section-start=SECTIONNAME=ORG: Options. (line 1293) +* --section-alignment: Options. (line 1937) +* --section-start=SECTIONNAME=ORG: Options. (line 1273) * --secure-plt: PowerPC ELF32. (line 26) -* --sort-common: Options. (line 1235) -* --sort-section=alignment: Options. (line 1250) -* --sort-section=name: Options. (line 1246) -* --split-by-file: Options. (line 1254) -* --split-by-reloc: Options. (line 1259) -* --stack: Options. (line 1960) +* --sort-common: Options. (line 1215) +* --sort-section=alignment: Options. (line 1230) +* --sort-section=name: Options. (line 1226) +* --split-by-file: Options. (line 1234) +* --split-by-reloc: Options. (line 1239) +* --stack: Options. (line 1943) * --stack-analysis: SPU ELF. (line 29) -* --stats: Options. (line 1272) -* --strip-all: Options. (line 519) -* --strip-debug: Options. (line 523) +* --stats: Options. (line 1252) +* --strip-all: Options. (line 512) +* --strip-debug: Options. (line 516) * --stub-group-size: PowerPC64 ELF64. (line 6) +* --stub-group-size=N: ARM. (line 137) * --stub-group-size=N <1>: HPPA ELF32. (line 12) -* --stub-group-size=N: ARM. (line 138) -* --subsystem: Options. (line 1967) +* --subsystem: Options. (line 1950) * --support-old-code: ARM. (line 6) -* --sysroot=DIRECTORY: Options. (line 1276) -* --target-help: Options. (line 983) +* --sysroot=DIRECTORY: Options. (line 1256) +* --target-help: Options. (line 972) * --target1-abs: ARM. (line 32) * --target1-rel: ARM. (line 32) * --target2=TYPE: ARM. (line 37) * --thumb-entry=ENTRY: ARM. (line 17) -* --trace: Options. (line 528) -* --trace-symbol=SYMBOL: Options. (line 597) -* --traditional-format: Options. (line 1281) -* --tsaware: Options. (line 2005) -* --undefined=SYMBOL: Options. (line 554) -* --unique[=SECTION]: Options. (line 572) -* --unresolved-symbols: Options. (line 1323) -* --use-blx: ARM. (line 74) +* --trace: Options. (line 521) +* --trace-symbol=SYMBOL: Options. (line 590) +* --traditional-format: Options. (line 1261) +* --tsaware: Options. (line 1988) +* --undefined=SYMBOL: Options. (line 547) +* --unique[=SECTION]: Options. (line 565) +* --unresolved-symbols: Options. (line 1303) +* --use-blx: ARM. (line 72) * --use-nul-prefixed-import-tables: ARM. (line 23) -* --verbose[=NUMBER]: Options. (line 1352) -* --version: Options. (line 581) -* --version-script=VERSION-SCRIPTFILE: Options. (line 1360) -* --vfp11-denorm-fix: ARM. (line 83) -* --warn-alternate-em: Options. (line 1472) -* --warn-common: Options. (line 1371) -* --warn-constructors: Options. (line 1439) -* --warn-multiple-gp: Options. (line 1444) -* --warn-once: Options. (line 1458) -* --warn-section-align: Options. (line 1462) -* --warn-shared-textrel: Options. (line 1469) -* --warn-unresolved-symbols: Options. (line 1475) -* --wdmdriver: Options. (line 2002) -* --whole-archive: Options. (line 1484) -* --wrap=SYMBOL: Options. (line 1498) -* -A ARCH: Options. (line 122) -* -a KEYWORD: Options. (line 105) -* -assert KEYWORD: Options. (line 762) -* -b FORMAT: Options. (line 134) -* -Bdynamic: Options. (line 765) -* -Bgroup: Options. (line 775) -* -Bshareable: Options. (line 1228) -* -Bstatic: Options. (line 782) -* -Bsymbolic: Options. (line 797) -* -Bsymbolic-functions: Options. (line 804) -* -c MRI-CMDFILE: Options. (line 158) -* -call_shared: Options. (line 765) -* -d: Options. (line 168) -* -dc: Options. (line 168) -* -dn: Options. (line 782) -* -dp: Options. (line 168) -* -dT SCRIPT: Options. (line 541) -* -dy: Options. (line 765) -* -E: Options. (line 221) -* -e ENTRY: Options. (line 187) -* -EB: Options. (line 248) -* -EL: Options. (line 251) -* -F NAME: Options. (line 276) -* -f NAME: Options. (line 255) -* -fini=NAME: Options. (line 300) -* -g: Options. (line 306) -* -G VALUE: Options. (line 309) -* -h NAME: Options. (line 317) -* -i: Options. (line 326) -* -IFILE: Options. (line 920) -* -init=NAME: Options. (line 329) -* -L DIR: Options. (line 368) -* -l NAMESPEC: Options. (line 335) -* -M: Options. (line 402) -* -m EMULATION: Options. (line 392) -* -Map=MAPFILE: Options. (line 987) -* -N: Options. (line 445) -* -n: Options. (line 439) -* -no-relax: Options. (line 1111) -* -non_shared: Options. (line 782) -* -nostdlib: Options. (line 1076) -* -O LEVEL: Options. (line 466) -* -o OUTPUT: Options. (line 460) -* -P AUDITLIB: Options. (line 177) -* -pie: Options. (line 1095) -* -q: Options. (line 476) -* -qmagic: Options. (line 1105) -* -Qy: Options. (line 1108) -* -r: Options. (line 489) -* -R FILE: Options. (line 508) -* -rpath-link=DIR: Options. (line 1173) -* -rpath=DIR: Options. (line 1151) -* -S: Options. (line 523) -* -s: Options. (line 519) -* -shared: Options. (line 1228) -* -soname=NAME: Options. (line 317) -* -static: Options. (line 782) -* -t: Options. (line 528) -* -T SCRIPT: Options. (line 532) -* -Tbss=ORG: Options. (line 1302) -* -Tdata=ORG: Options. (line 1302) -* -Tldata-segment=ORG: Options. (line 1318) -* -Trodata-segment=ORG: Options. (line 1312) -* -Ttext-segment=ORG: Options. (line 1308) -* -Ttext=ORG: Options. (line 1302) -* -u SYMBOL: Options. (line 554) -* -Ur: Options. (line 562) -* -V: Options. (line 581) -* -v: Options. (line 581) -* -X: Options. (line 591) -* -x: Options. (line 587) -* -Y PATH: Options. (line 606) -* -y SYMBOL: Options. (line 597) -* -z defs: Options. (line 998) -* -z KEYWORD: Options. (line 610) -* -z muldefs: Options. (line 1006) +* --verbose[=NUMBER]: Options. (line 1332) +* --version: Options. (line 574) +* --version-script=VERSION-SCRIPTFILE: Options. (line 1340) +* --vfp11-denorm-fix: ARM. (line 81) +* --warn-alternate-em: Options. (line 1451) +* --warn-common: Options. (line 1350) +* --warn-constructors: Options. (line 1418) +* --warn-multiple-gp: Options. (line 1423) +* --warn-once: Options. (line 1437) +* --warn-section-align: Options. (line 1441) +* --warn-shared-textrel: Options. (line 1448) +* --warn-unresolved-symbols: Options. (line 1454) +* --wdmdriver: Options. (line 1985) +* --whole-archive: Options. (line 1463) +* --wrap=SYMBOL: Options. (line 1477) +* -A ARCH: Options. (line 121) +* -a KEYWORD: Options. (line 104) +* -assert KEYWORD: Options. (line 751) +* -b FORMAT: Options. (line 133) +* -Bdynamic: Options. (line 754) +* -Bgroup: Options. (line 764) +* -Bshareable: Options. (line 1208) +* -Bstatic: Options. (line 771) +* -Bsymbolic: Options. (line 785) +* -Bsymbolic-functions: Options. (line 792) +* -c MRI-CMDFILE: Options. (line 157) +* -call_shared: Options. (line 754) +* -d: Options. (line 167) +* -dc: Options. (line 167) +* -dn: Options. (line 771) +* -dp: Options. (line 167) +* -dT SCRIPT: Options. (line 534) +* -dy: Options. (line 754) +* -E: Options. (line 220) +* -e ENTRY: Options. (line 186) +* -EB: Options. (line 247) +* -EL: Options. (line 250) +* -f NAME: Options. (line 254) +* -F NAME: Options. (line 275) +* -fini=NAME: Options. (line 298) +* -g: Options. (line 304) +* -G VALUE: Options. (line 307) +* -h NAME: Options. (line 314) +* -i: Options. (line 323) +* -IFILE: Options. (line 909) +* -init=NAME: Options. (line 326) +* -L DIR: Options. (line 365) +* -l NAMESPEC: Options. (line 332) +* -M: Options. (line 399) +* -m EMULATION: Options. (line 389) +* -Map=MAPFILE: Options. (line 976) +* -n: Options. (line 433) +* -N: Options. (line 439) +* -no-relax: Options. (line 1098) +* -non_shared: Options. (line 771) +* -nostdlib: Options. (line 1064) +* -O LEVEL: Options. (line 460) +* -o OUTPUT: Options. (line 454) +* -P AUDITLIB: Options. (line 176) +* -pie: Options. (line 1082) +* -q: Options. (line 470) +* -qmagic: Options. (line 1092) +* -Qy: Options. (line 1095) +* -r: Options. (line 483) +* -R FILE: Options. (line 501) +* -rpath-link=DIR: Options. (line 1160) +* -rpath=DIR: Options. (line 1138) +* -s: Options. (line 512) +* -S: Options. (line 516) +* -shared: Options. (line 1208) +* -soname=NAME: Options. (line 314) +* -static: Options. (line 771) +* -t: Options. (line 521) +* -T SCRIPT: Options. (line 525) +* -Tbss=ORG: Options. (line 1282) +* -Tdata=ORG: Options. (line 1282) +* -Tldata-segment=ORG: Options. (line 1298) +* -Trodata-segment=ORG: Options. (line 1292) +* -Ttext-segment=ORG: Options. (line 1288) +* -Ttext=ORG: Options. (line 1282) +* -u SYMBOL: Options. (line 547) +* -Ur: Options. (line 555) +* -v: Options. (line 574) +* -V: Options. (line 574) +* -x: Options. (line 580) +* -X: Options. (line 584) +* -Y PATH: Options. (line 599) +* -y SYMBOL: Options. (line 590) +* -z defs: Options. (line 987) +* -z KEYWORD: Options. (line 603) +* -z muldefs: Options. (line 995) * .: Location Counter. (line 6) * /DISCARD/: Output Section Discarding. (line 21) @@ -7503,84 +7449,87 @@ LD Index (line 6) * [COMMON]: Input Section Common. (line 29) -* ABSOLUTE (MRI): MRI. (line 33) +* 'ABSOLUTE' (MRI): MRI. (line 32) * absolute and relocatable symbols: Expression Section. (line 6) * absolute expressions: Expression Section. (line 6) * ABSOLUTE(EXP): Builtin Functions. (line 10) * ADDR(SECTION): Builtin Functions. (line 17) * address, section: Output Section Address. (line 6) -* ALIAS (MRI): MRI. (line 44) -* ALIGN (MRI): MRI. (line 50) +* 'ALIAS' (MRI): MRI. (line 43) +* 'ALIGN' (MRI): MRI. (line 49) * align expression: Builtin Functions. (line 38) * align location counter: Builtin Functions. (line 38) * ALIGN(ALIGN): Builtin Functions. (line 38) * ALIGN(EXP,ALIGN): Builtin Functions. (line 38) * ALIGN(SECTION_ALIGN): Forced Output Alignment. (line 6) -* aligned common symbols: WIN32. (line 424) +* aligned common symbols: WIN32. (line 415) * ALIGNOF(SECTION): Builtin Functions. (line 63) * allocating memory: MEMORY. (line 6) * architecture: Miscellaneous Commands. (line 72) -* architectures: Options. (line 122) -* archive files, from cmd line: Options. (line 335) +* architectures: Options. (line 121) +* archive files, from cmd line: Options. (line 332) * archive search path in linker script: File Commands. (line 74) * arithmetic: Expressions. (line 6) * arithmetic operators: Operators. (line 6) * ARM interworking support: ARM. (line 6) -* ARM1176 erratum workaround: ARM. (line 111) -* AS_NEEDED(FILES): File Commands. (line 54) +* ARM1176 erratum workaround: ARM. (line 110) * ASSERT: Miscellaneous Commands. (line 9) * assertion in linker script: Miscellaneous Commands. (line 9) * assignment in scripts: Assignments. (line 6) +* AS_NEEDED(FILES): File Commands. (line 54) * AT(LMA): Output Section LMA. (line 6) * AT>LMA_REGION: Output Section LMA. (line 6) -* automatic data imports: WIN32. (line 191) +* automatic data imports: WIN32. (line 185) * back end: BFD. (line 6) -* BASE (MRI): MRI. (line 54) +* 'BASE' (MRI): MRI. (line 53) * BE8: ARM. (line 28) * BFD canonical format: Canonical format. (line 11) * BFD requirements: BFD. (line 16) -* big-endian objects: Options. (line 248) -* binary input format: Options. (line 134) +* big-endian objects: Options. (line 247) +* binary input format: Options. (line 133) * BLOCK(EXP): Builtin Functions. (line 76) * bug criteria: Bug Criteria. (line 6) * bug reports: Bug Reporting. (line 6) -* bugs in ld: Reporting Bugs. (line 6) +* bugs in 'ld': Reporting Bugs. (line 6) * BYTE(EXPRESSION): Output Section Data. (line 6) * C++ constructors, arranging in link: Output Section Keywords. (line 19) -* CHIP (MRI): MRI. (line 58) +* 'CHIP' (MRI): MRI. (line 57) * COLLECT_NO_DEMANGLE: Environment. (line 29) -* combining symbols, warnings on: Options. (line 1371) +* combining symbols, warnings on: Options. (line 1350) * command files: Scripts. (line 6) * command line: Options. (line 6) -* common allocation: Options. (line 168) +* common allocation: Options. (line 167) +* common allocation <1>: Options. (line 867) * common allocation in linker script: Miscellaneous Commands. (line 20) +* common allocation in linker script <1>: Miscellaneous Commands. + (line 25) * common symbol placement: Input Section Common. (line 6) * COMMONPAGESIZE: Symbolic Constants. (line 13) -* compatibility, MRI: Options. (line 158) +* compatibility, MRI: Options. (line 157) * CONSTANT: Symbolic Constants. (line 6) * constants in linker scripts: Constants. (line 6) * constraints on output sections: Output Section Constraint. (line 6) +* constructors: Options. (line 555) * CONSTRUCTORS: Output Section Keywords. (line 19) -* constructors: Options. (line 562) * constructors, arranging in link: Output Section Keywords. (line 19) -* Cortex-A8 erratum workaround: i960. (line 39) +* Cortex-A8 erratum workaround: i960. (line 40) * crash of linker: Bug Criteria. (line 9) * CREATE_OBJECT_SYMBOLS: Output Section Keywords. (line 9) -* creating a DEF file: WIN32. (line 158) -* cross reference table: Options. (line 866) +* creating a DEF file: WIN32. (line 153) +* cross reference table: Options. (line 854) * cross references: Miscellaneous Commands. (line 56) * current output location: Location Counter. (line 6) @@ -7590,32 +7539,34 @@ LD Index (line 81) * DATA_SEGMENT_END(EXP): Builtin Functions. (line 102) * DATA_SEGMENT_RELRO_END(OFFSET, EXP): Builtin Functions. (line 108) -* dbx: Options. (line 1286) -* DEF files, creating: Options. (line 1771) +* dbx: Options. (line 1266) +* DEF files, creating: Options. (line 1756) * default emulation: Environment. (line 21) * default input format: Environment. (line 9) * DEFINED(SYMBOL): Builtin Functions. (line 119) -* deleting local symbols: Options. (line 587) +* deleting local symbols: Options. (line 580) * demangling, default: Environment. (line 29) -* demangling, from command line: Options. (line 907) -* direct linking to a dll: WIN32. (line 239) +* demangling, from command line: Options. (line 896) +* direct linking to a dll: WIN32. (line 233) * discarding sections: Output Section Discarding. (line 6) * discontinuous memory: MEMORY. (line 6) -* DLLs, creating: Options. (line 1673) -* DLLs, linking to: Options. (line 1802) +* DLLs, creating: Options. (line 1651) +* DLLs, creating <1>: Options. (line 1756) +* DLLs, creating <2>: Options. (line 1764) +* DLLs, linking to: Options. (line 1786) * dot: Location Counter. (line 6) * dot inside sections: Location Counter. (line 36) * dot outside sections: Location Counter. (line 66) -* dynamic linker, from command line: Options. (line 920) -* dynamic symbol table: Options. (line 221) +* dynamic linker, from command line: Options. (line 909) +* dynamic symbol table: Options. (line 220) * ELF program headers: PHDRS. (line 6) -* emulation: Options. (line 392) +* emulation: Options. (line 389) * emulation, default: Environment. (line 21) -* END (MRI): MRI. (line 62) -* endianness: Options. (line 248) +* 'END' (MRI): MRI. (line 61) +* endianness: Options. (line 247) * entry point: Entry Point. (line 6) -* entry point, from command line: Options. (line 187) +* entry point, from command line: Options. (line 186) * entry point, thumb: ARM. (line 17) * ENTRY(SYMBOL): Entry Point. (line 6) * error on valid input: Bug Criteria. (line 12) @@ -7637,32 +7588,33 @@ LD Index (line 6) * FILL(EXPRESSION): Output Section Data. (line 39) -* finalization function: Options. (line 300) +* finalization function: Options. (line 298) * first input file: File Commands. (line 82) * first instruction: Entry Point. (line 6) -* FIX_V4BX: ARM. (line 49) -* FIX_V4BX_INTERWORKING: ARM. (line 62) +* FIX_V4BX: ARM. (line 47) +* FIX_V4BX_INTERWORKING: ARM. (line 60) * FORCE_COMMON_ALLOCATION: Miscellaneous Commands. (line 20) * forcing input section alignment: Forced Input Alignment. (line 6) * forcing output section alignment: Forced Output Alignment. (line 6) -* forcing the creation of dynamic sections: Options. (line 485) -* FORMAT (MRI): MRI. (line 66) +* forcing the creation of dynamic sections: Options. (line 479) +* 'FORMAT' (MRI): MRI. (line 65) * functions in expressions: Builtin Functions. (line 6) -* garbage collection <1>: Input Section Keep. (line 6) -* garbage collection: Options. (line 942) -* generating optimized output: Options. (line 466) +* garbage collection: Options. (line 931) +* garbage collection <1>: Options. (line 953) +* garbage collection <2>: Input Section Keep. (line 6) +* generating optimized output: Options. (line 460) * GNU linker: Overview. (line 6) * GNUTARGET: Environment. (line 9) * GROUP(FILES): File Commands. (line 47) * grouping input files: File Commands. (line 47) -* groups of archives: Options. (line 710) +* groups of archives: Options. (line 699) * H8/300 support: H8/300. (line 6) -* header size: Builtin Functions. (line 182) -* heap size: Options. (line 1713) -* help: Options. (line 979) +* header size: Builtin Functions. (line 186) +* heap size: Options. (line 1691) +* help: Options. (line 968) * HIDDEN: HIDDEN. (line 6) * holes: Location Counter. (line 12) * holes, filling: Output Section Data. @@ -7670,24 +7622,25 @@ LD Index * HPPA multiple sub-space stubs: HPPA ELF32. (line 6) * HPPA stub grouping: HPPA ELF32. (line 12) * i960 support: i960. (line 6) -* image base: Options. (line 1720) +* image base: Options. (line 1698) * implicit linker scripts: Implicit Linker Scripts. (line 6) * import libraries: WIN32. (line 10) * INCLUDE FILENAME: File Commands. (line 9) * including a linker script: File Commands. (line 9) -* including an entire archive: Options. (line 1484) -* incremental link: Options. (line 326) +* including an entire archive: Options. (line 1463) +* incremental link: Options. (line 323) * INHIBIT_COMMON_ALLOCATION: Miscellaneous Commands. (line 25) -* initialization function: Options. (line 329) +* initialization function: Options. (line 326) * initialized data in ROM: Output Section LMA. (line 39) * input file format in linker script: Format Commands. (line 35) * input filename symbols: Output Section Keywords. (line 9) * input files in linker scripts: File Commands. (line 19) -* input files, displaying: Options. (line 528) -* input format: Options. (line 134) +* input files, displaying: Options. (line 521) +* input format: Options. (line 133) +* input format <1>: Options. (line 133) * input object files in linker scripts: File Commands. (line 19) * input section alignment: Forced Input Alignment. (line 6) @@ -7707,19 +7660,19 @@ LD Index * invalid input: Bug Criteria. (line 14) * K and M integer suffixes: Constants. (line 15) * KEEP: Input Section Keep. (line 6) -* l =: MEMORY. (line 74) +* l =: MEMORY. (line 68) * lazy evaluation: Evaluation. (line 6) -* ld bugs, reporting: Bug Reporting. (line 6) +* 'ld' bugs, reporting: Bug Reporting. (line 6) +* ldata segment origin, cmd line: Options. (line 1299) +* LDEMULATION: Environment. (line 21) * LD_FEATURE(STRING): Miscellaneous Commands. (line 78) -* ldata segment origin, cmd line: Options. (line 1319) -* LDEMULATION: Environment. (line 21) -* len =: MEMORY. (line 74) -* LENGTH =: MEMORY. (line 74) +* len =: MEMORY. (line 68) +* LENGTH =: MEMORY. (line 68) * LENGTH(MEMORY): Builtin Functions. (line 136) * library search path in linker script: File Commands. (line 74) -* link map: Options. (line 402) -* link-time runtime library search path: Options. (line 1173) +* link map: Options. (line 399) +* link-time runtime library search path: Options. (line 1160) * linker crash: Bug Criteria. (line 9) * linker script concepts: Basic Script Concepts. (line 6) @@ -7729,56 +7682,59 @@ LD Index * linker script input object files: File Commands. (line 19) * linker script simple commands: Simple Commands. (line 6) * linker scripts: Scripts. (line 6) -* LIST (MRI): MRI. (line 77) -* little-endian objects: Options. (line 251) -* LOAD (MRI): MRI. (line 84) +* 'LIST' (MRI): MRI. (line 76) +* little-endian objects: Options. (line 250) +* 'LOAD' (MRI): MRI. (line 83) * load address: Output Section LMA. (line 6) * LOADADDR(SECTION): Builtin Functions. (line 139) * loading, preventing: Output Section Type. - (line 22) -* local symbols, deleting: Options. (line 591) + (line 21) +* local symbols, deleting: Options. (line 584) * location counter: Location Counter. (line 6) +* LOG2CEIL(EXP): Builtin Functions. (line 143) * LONG(EXPRESSION): Output Section Data. (line 6) * M and K integer suffixes: Constants. (line 15) -* M68HC11 and 68HC12 support: M68HC11/68HC12. (line 6) +* M68HC11 and 68HC12 support: M68HC11/68HC12. (line 5) * machine architecture: Miscellaneous Commands. (line 72) * machine dependencies: Machine Dependent. (line 6) * mapping input sections to output sections: Input Section. (line 6) -* MAX: Builtin Functions. (line 142) +* MAX: Builtin Functions. (line 146) * MAXPAGESIZE: Symbolic Constants. (line 10) * MEMORY: MEMORY. (line 6) * memory region attributes: MEMORY. (line 34) * memory regions: MEMORY. (line 6) * memory regions and sections: Output Section Region. (line 6) -* memory usage: Options. (line 991) -* MIN: Builtin Functions. (line 145) +* memory usage: Options. (line 980) +* MIN: Builtin Functions. (line 149) +* MIPS microMIPS instruction choice selection: MIPS. (line 6) * Motorola 68K GOT generation: M68K. (line 6) * MRI compatibility: MRI. (line 6) * MSP430 extra sections: MSP430. (line 11) -* NAME (MRI): MRI. (line 90) +* 'NAME' (MRI): MRI. (line 89) * name, section: Output Section Name. (line 6) * names: Symbols. (line 6) -* naming the output file: Options. (line 460) -* NEXT(EXP): Builtin Functions. (line 149) -* NMAGIC: Options. (line 439) -* NO_ENUM_SIZE_WARNING: ARM. (line 120) -* NO_WCHAR_SIZE_WARNING: ARM. (line 127) +* naming the output file: Options. (line 454) +* NEXT(EXP): Builtin Functions. (line 153) +* NMAGIC: Options. (line 433) * NOCROSSREFS(SECTIONS): Miscellaneous Commands. (line 56) * NOLOAD: Output Section Type. - (line 22) -* not enough room for program headers: Builtin Functions. (line 187) -* o =: MEMORY. (line 69) + (line 21) +* not enough room for program headers: Builtin Functions. (line 191) +* NO_ENUM_SIZE_WARNING: ARM. (line 119) +* NO_WCHAR_SIZE_WARNING: ARM. (line 126) +* o =: MEMORY. (line 63) * objdump -i: BFD. (line 6) * object file management: BFD. (line 6) * object files: Options. (line 29) * object formats available: BFD. (line 6) -* object size: Options. (line 309) -* OMAGIC: Options. (line 445) +* object size: Options. (line 307) +* OMAGIC: Options. (line 439) +* OMAGIC <1>: Options. (line 448) * ONLY_IF_RO: Output Section Constraint. (line 6) * ONLY_IF_RW: Output Section Constraint. @@ -7786,15 +7742,15 @@ LD Index * opening object files: BFD outline. (line 6) * operators for arithmetic: Operators. (line 6) * options: Options. (line 6) -* ORDER (MRI): MRI. (line 95) -* org =: MEMORY. (line 69) -* ORIGIN =: MEMORY. (line 69) -* ORIGIN(MEMORY): Builtin Functions. (line 155) +* 'ORDER' (MRI): MRI. (line 94) +* org =: MEMORY. (line 63) +* ORIGIN =: MEMORY. (line 63) +* ORIGIN(MEMORY): Builtin Functions. (line 159) * orphan: Orphan Sections. (line 6) -* output file after errors: Options. (line 1070) +* output file after errors: Options. (line 1058) * output file format in linker script: Format Commands. (line 10) * output file name in linker script: File Commands. (line 64) -* output format: Options. (line 973) +* output format: Options. (line 962) * output section alignment: Forced Output Alignment. (line 6) * output section attributes: Output Section Attributes. @@ -7809,11 +7765,12 @@ LD Index (line 6) * overlays: Overlay Description. (line 6) -* partial link: Options. (line 489) +* partial link: Options. (line 483) * PE import table prefixing: ARM. (line 23) * PHDRS: PHDRS. (line 6) -* PIC_VENEER: ARM. (line 133) -* position independent executables: Options. (line 1097) +* PHDRS <1>: PHDRS. (line 62) +* PIC_VENEER: ARM. (line 132) +* position independent executables: Options. (line 1084) * PowerPC ELF32 options: PowerPC ELF32. (line 16) * PowerPC GOT: PowerPC ELF32. (line 33) * PowerPC long branches: PowerPC ELF32. (line 6) @@ -7835,59 +7792,60 @@ LD Index * PowerPC64 TOC sorting: PowerPC64 ELF64. (line 86) * precedence in expressions: Operators. (line 6) * prevent unnecessary loading: Output Section Type. - (line 22) + (line 21) * program headers: PHDRS. (line 6) * program headers and sections: Output Section Phdr. (line 6) -* program headers, not enough room: Builtin Functions. (line 187) +* program headers, not enough room: Builtin Functions. (line 191) * program segments: PHDRS. (line 6) * PROVIDE: PROVIDE. (line 6) * PROVIDE_HIDDEN: PROVIDE_HIDDEN. (line 6) -* PUBLIC (MRI): MRI. (line 103) +* 'PUBLIC' (MRI): MRI. (line 102) * QUAD(EXPRESSION): Output Section Data. (line 6) * quoted symbol names: Symbols. (line 6) -* read-only text: Options. (line 439) -* read/write from cmd line: Options. (line 445) +* read-only text: Options. (line 433) +* read/write from cmd line: Options. (line 439) * region alias: REGION_ALIAS. (line 6) * region names: REGION_ALIAS. (line 6) -* REGION_ALIAS(ALIAS, REGION): REGION_ALIAS. (line 6) * regions of memory: MEMORY. (line 6) +* REGION_ALIAS(ALIAS, REGION): REGION_ALIAS. (line 6) * relative expressions: Expression Section. (line 6) -* relaxing addressing modes: Options. (line 1111) +* relaxing addressing modes: Options. (line 1098) * relaxing on H8/300: H8/300. (line 9) -* relaxing on i960: i960. (line 31) +* relaxing on i960: i960. (line 32) * relaxing on M68HC11: M68HC11/68HC12. (line 12) * relaxing on Xtensa: Xtensa. (line 27) * relocatable and absolute symbols: Expression Section. (line 6) -* relocatable output: Options. (line 489) +* relocatable output: Options. (line 483) * removing sections: Output Section Discarding. (line 6) -* reporting bugs in ld: Reporting Bugs. (line 6) +* reporting bugs in 'ld': Reporting Bugs. (line 6) * requirements for BFD: BFD. (line 16) -* retain relocations in final executable: Options. (line 476) -* retaining specified symbols: Options. (line 1137) -* rodata segment origin, cmd line: Options. (line 1313) +* retain relocations in final executable: Options. (line 470) +* retaining specified symbols: Options. (line 1124) +* rodata segment origin, cmd line: Options. (line 1293) * ROM initialized data: Output Section LMA. (line 39) * round up expression: Builtin Functions. (line 38) * round up location counter: Builtin Functions. (line 38) -* runtime library name: Options. (line 317) -* runtime library search path: Options. (line 1151) -* runtime pseudo-relocation: WIN32. (line 217) +* runtime library name: Options. (line 314) +* runtime library search path: Options. (line 1138) +* runtime pseudo-relocation: WIN32. (line 211) * scaled integers: Constants. (line 15) * scommon section: Input Section Common. (line 20) -* script files: Options. (line 532) +* script files: Options. (line 525) +* script files <1>: Options. (line 534) * scripts: Scripts. (line 6) -* search directory, from cmd line: Options. (line 368) +* search directory, from cmd line: Options. (line 365) * search path in linker script: File Commands. (line 74) * SEARCH_DIR(PATH): File Commands. (line 74) -* SECT (MRI): MRI. (line 109) +* 'SECT' (MRI): MRI. (line 108) * section address: Output Section Address. (line 6) * section address in expression: Builtin Functions. (line 17) * section alignment: Builtin Functions. (line 63) -* section alignment, warnings on: Options. (line 1462) +* section alignment, warnings on: Options. (line 1441) * section data: Output Section Data. (line 6) * section fill pattern: Output Section Fill. @@ -7898,7 +7856,7 @@ LD Index (line 6) * section name wildcard patterns: Input Section Wildcards. (line 6) -* section size: Builtin Functions. (line 166) +* section size: Builtin Functions. (line 170) * section, assigning to memory region: Output Section Region. (line 6) * section, assigning to program header: Output Section Phdr. @@ -7906,27 +7864,28 @@ LD Index * SECTIONS: SECTIONS. (line 6) * sections, discarding: Output Section Discarding. (line 6) -* segment origins, cmd line: Options. (line 1302) -* SEGMENT_START(SEGMENT, DEFAULT): Builtin Functions. (line 158) +* segment origins, cmd line: Options. (line 1282) * segments, ELF: PHDRS. (line 6) -* shared libraries: Options. (line 1230) +* SEGMENT_START(SEGMENT, DEFAULT): Builtin Functions. (line 162) +* shared libraries: Options. (line 1210) * SHORT(EXPRESSION): Output Section Data. (line 6) -* SIZEOF(SECTION): Builtin Functions. (line 166) -* SIZEOF_HEADERS: Builtin Functions. (line 182) +* SIZEOF(SECTION): Builtin Functions. (line 170) +* SIZEOF_HEADERS: Builtin Functions. (line 186) * small common symbols: Input Section Common. (line 20) * SORT: Input Section Wildcards. - (line 63) + (line 62) * SORT_BY_ALIGNMENT: Input Section Wildcards. - (line 54) + (line 51) * SORT_BY_INIT_PRIORITY: Input Section Wildcards. - (line 58) + (line 57) * SORT_BY_NAME: Input Section Wildcards. - (line 46) + (line 43) * SORT_NONE: Input Section Wildcards. - (line 104) + (line 98) * SPU: SPU ELF. (line 29) +* SPU <1>: SPU ELF. (line 46) * SPU ELF options: SPU ELF. (line 6) * SPU extra overlay stubs: SPU ELF. (line 19) * SPU local store size: SPU ELF. (line 24) @@ -7935,155 +7894,156 @@ LD Index * SPU plugins: SPU ELF. (line 6) * SQUAD(EXPRESSION): Output Section Data. (line 6) -* stack size: Options. (line 1960) +* stack size: Options. (line 1943) * standard Unix system: Options. (line 7) * start of execution: Entry Point. (line 6) * STARTUP(FILENAME): File Commands. (line 82) -* strip all symbols: Options. (line 519) -* strip debugger symbols: Options. (line 523) -* stripping all but some symbols: Options. (line 1137) -* STUB_GROUP_SIZE: ARM. (line 138) +* strip all symbols: Options. (line 512) +* strip debugger symbols: Options. (line 516) +* stripping all but some symbols: Options. (line 1124) +* STUB_GROUP_SIZE: ARM. (line 137) * SUBALIGN(SUBSECTION_ALIGN): Forced Input Alignment. (line 6) * suffixes for integers: Constants. (line 15) * symbol defaults: Builtin Functions. (line 119) * symbol definition, scripts: Assignments. (line 6) * symbol names: Symbols. (line 6) -* symbol tracing: Options. (line 597) +* symbol tracing: Options. (line 590) * symbol versions: VERSION. (line 6) -* symbol-only input: Options. (line 508) +* symbol-only input: Options. (line 501) * symbolic constants: Symbolic Constants. (line 6) -* symbols, from command line: Options. (line 894) +* symbols, from command line: Options. (line 883) * symbols, relocatable and absolute: Expression Section. (line 6) -* symbols, retaining selectively: Options. (line 1137) -* synthesizing linker: Options. (line 1111) +* symbols, retaining selectively: Options. (line 1124) +* synthesizing linker: Options. (line 1098) * synthesizing on H8/300: H8/300. (line 14) * TARGET(BFDNAME): Format Commands. (line 35) * TARGET1: ARM. (line 32) * TARGET2: ARM. (line 37) -* text segment origin, cmd line: Options. (line 1309) +* text segment origin, cmd line: Options. (line 1289) * thumb entry point: ARM. (line 17) * TI COFF versions: TI COFF. (line 6) -* traditional format: Options. (line 1281) -* trampoline generation on M68HC11: M68HC11/68HC12. (line 31) -* trampoline generation on M68HC12: M68HC11/68HC12. (line 31) -* unallocated address, next: Builtin Functions. (line 149) -* undefined symbol: Options. (line 554) +* traditional format: Options. (line 1261) +* trampoline generation on M68HC11: M68HC11/68HC12. (line 30) +* trampoline generation on M68HC12: M68HC11/68HC12. (line 30) +* unallocated address, next: Builtin Functions. (line 153) +* undefined symbol: Options. (line 547) * undefined symbol in linker script: Miscellaneous Commands. (line 13) -* undefined symbols, warnings on: Options. (line 1458) +* undefined symbols, warnings on: Options. (line 1437) * uninitialized data placement: Input Section Common. (line 6) * unspecified memory: Output Section Data. (line 39) -* usage: Options. (line 979) -* USE_BLX: ARM. (line 74) -* using a DEF file: WIN32. (line 57) +* usage: Options. (line 968) +* USE_BLX: ARM. (line 72) +* using a DEF file: WIN32. (line 52) * using auto-export functionality: WIN32. (line 22) -* Using decorations: WIN32. (line 162) +* Using decorations: WIN32. (line 157) * variables, defining: Assignments. (line 6) -* verbose[=NUMBER]: Options. (line 1352) -* version: Options. (line 581) +* verbose[=NUMBER]: Options. (line 1332) +* version: Options. (line 574) * version script: VERSION. (line 6) -* version script, symbol versions: Options. (line 1360) +* version script, symbol versions: Options. (line 1340) * VERSION {script text}: VERSION. (line 6) * versions of symbols: VERSION. (line 6) -* VFP11_DENORM_FIX: ARM. (line 83) -* warnings, on combining symbols: Options. (line 1371) -* warnings, on section alignment: Options. (line 1462) -* warnings, on undefined symbols: Options. (line 1458) -* weak externals: WIN32. (line 407) +* VFP11_DENORM_FIX: ARM. (line 81) +* warnings, on combining symbols: Options. (line 1350) +* warnings, on section alignment: Options. (line 1441) +* warnings, on undefined symbols: Options. (line 1437) +* weak externals: WIN32. (line 400) * what is this?: Overview. (line 6) * wildcard file name patterns: Input Section Wildcards. (line 6) -* Xtensa options: Xtensa. (line 56) +* Xtensa options: Xtensa. (line 55) * Xtensa processors: Xtensa. (line 6) Tag Table: -Node: Top840 -Node: Overview1636 -Node: Invocation2750 -Node: Options3158 -Node: Environment96090 -Node: Scripts97850 -Node: Basic Script Concepts99584 -Node: Script Format102292 -Node: Simple Example103155 -Node: Simple Commands106251 -Node: Entry Point106757 -Node: File Commands107690 -Node: Format Commands111691 -Node: REGION_ALIAS113647 -Node: Miscellaneous Commands118479 -Node: Assignments122087 -Node: Simple Assignments122598 -Node: HIDDEN124333 -Node: PROVIDE124963 -Node: PROVIDE_HIDDEN126156 -Node: Source Code Reference126400 -Node: SECTIONS129980 -Node: Output Section Description131871 -Node: Output Section Name132958 -Node: Output Section Address133834 -Node: Input Section136069 -Node: Input Section Basics136870 -Node: Input Section Wildcards140776 -Node: Input Section Common145870 -Node: Input Section Keep147352 -Node: Input Section Example147842 -Node: Output Section Data148810 -Node: Output Section Keywords151587 -Node: Output Section Discarding155156 -Node: Output Section Attributes156337 -Node: Output Section Type157438 -Node: Output Section LMA158509 -Node: Forced Output Alignment161580 -Node: Forced Input Alignment161848 -Node: Output Section Constraint162237 -Node: Output Section Region162665 -Node: Output Section Phdr163098 -Node: Output Section Fill163762 -Node: Overlay Description164904 -Node: MEMORY169211 -Node: PHDRS173545 -Node: VERSION178799 -Node: Expressions186892 -Node: Constants187821 -Node: Symbolic Constants188696 -Node: Symbols189247 -Node: Orphan Sections189994 -Node: Location Counter191159 -Node: Operators195595 -Node: Evaluation196517 -Node: Expression Section197881 -Node: Builtin Functions201745 -Node: Implicit Linker Scripts209701 -Node: Machine Dependent210476 -Node: H8/300211492 -Node: i960213554 -Node: M68HC11/68HC12215769 -Node: ARM217211 -Node: HPPA ELF32225185 -Node: M68K226808 -Node: MMIX227717 -Node: MSP430228882 -Node: PowerPC ELF32229930 -Node: PowerPC64 ELF64232758 -Node: SPU ELF238914 -Node: TI COFF241546 -Node: WIN32242072 -Node: Xtensa262197 -Node: BFD265162 -Node: BFD outline266617 -Node: BFD information loss267903 -Node: Canonical format270420 -Node: Reporting Bugs274777 -Node: Bug Criteria275471 -Node: Bug Reporting276170 -Node: MRI283240 -Node: GNU Free Documentation License287883 -Node: LD Index313039 +Node: Top708 +Node: Overview1491 +Node: Invocation2607 +Node: Options3015 +Node: Environment97116 +Node: Scripts98877 +Node: Basic Script Concepts100611 +Node: Script Format103319 +Node: Simple Example104182 +Node: Simple Commands107276 +Node: Entry Point107781 +Node: File Commands108709 +Node: Format Commands112711 +Node: REGION_ALIAS114667 +Node: Miscellaneous Commands119494 +Node: Assignments123102 +Node: Simple Assignments123613 +Node: HIDDEN125344 +Node: PROVIDE125971 +Node: PROVIDE_HIDDEN127164 +Node: Source Code Reference127408 +Node: SECTIONS130990 +Node: Output Section Description132878 +Node: Output Section Name133981 +Node: Output Section Address134858 +Node: Input Section137091 +Node: Input Section Basics137892 +Node: Input Section Wildcards141791 +Node: Input Section Common146992 +Node: Input Section Keep148474 +Node: Input Section Example148964 +Node: Output Section Data149932 +Node: Output Section Keywords152711 +Node: Output Section Discarding156278 +Node: Output Section Attributes157456 +Node: Output Section Type158556 +Node: Output Section LMA159626 +Node: Forced Output Alignment162697 +Node: Forced Input Alignment163213 +Node: Output Section Constraint163601 +Node: Output Section Region164029 +Node: Output Section Phdr164462 +Node: Output Section Fill165126 +Node: Overlay Description166268 +Node: MEMORY170575 +Node: PHDRS174903 +Node: VERSION180157 +Node: Expressions188248 +Node: Constants189177 +Node: Symbolic Constants190051 +Node: Symbols190602 +Node: Orphan Sections191349 +Node: Location Counter192514 +Node: Operators196948 +Node: Evaluation197870 +Node: Expression Section199234 +Node: Builtin Functions203089 +Node: Implicit Linker Scripts211171 +Node: Machine Dependent211946 +Node: H8/300212984 +Node: i960215047 +Node: M68HC11/68HC12217262 +Node: ARM218707 +Node: HPPA ELF32226687 +Node: M68K228310 +Node: MIPS229219 +Node: MMIX229743 +Node: MSP430230908 +Node: PowerPC ELF32231956 +Node: PowerPC64 ELF64234786 +Node: SPU ELF240940 +Node: TI COFF243574 +Node: WIN32244100 +Node: Xtensa264229 +Node: BFD267195 +Node: BFD outline268653 +Node: BFD information loss269941 +Node: Canonical format272467 +Node: Reporting Bugs276829 +Node: Bug Criteria277523 +Node: Bug Reporting278222 +Node: MRI285260 +Node: GNU Free Documentation License289902 +Node: LD Index315038 End Tag Table |