Remove futility linker script.

The futility.lds linker script was used to generate a table with
all the symbols in a specific section called .futil_cmds listed
in order under the symbol "futil_cmds". This allows the source files
to define a command and let the linker figure out the list of
compiled commands. Nevertheless, passing this linker script
makes the linker leave a gap of about 2MiB in the output ELF file.

Instead of mess up with linker scripts just to generate a table of
commands, this patch generates such table in the Makefile looking
at the included sources and compiling that table. The result is a
futility binary of about 88 KiB instead of the 2.1 MiB required
originally.

This patch also adds sys-boot/chromeos-u-boot to the list of ebuilds
tested by emerge_test.sh.

BUG=chromium:408926
BRANCH=None
TEST=BOARD=link ./emerge_test.sh
TEST=BOARD=daisy_spring ./emerge_test.sh
TEST=`readelf -S futility` shows no gap.
TEST=/usr/bin/futility shows no difference in the help output.

Change-Id: I9c0febc76140b404d48aa13e7f948e8ea77a41b5
Reviewed-on: https://chromium-review.googlesource.com/215496
Tested-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>

2 files changed, 2 insertions, 20 deletions

diff --git a/futility/futility.h b/futility/futility.h
index 32c553db..dfccf6f9 100644
--- a/futility/futility.h
+++ b/futility/futility.h
@@ -23,14 +23,11 @@ struct futil_cmd_t {
  * to them without explictly declaring every function in a header somewhere.
  */
 #define DECLARE_FUTIL_COMMAND(NAME, HANDLER, SHORTHELP)           \
-        static const struct futil_cmd_t __cmd_##NAME = {          \
+        const struct futil_cmd_t __cmd_##NAME = {                 \
                 .name = #NAME,                                    \
                 .handler = HANDLER,                               \
                 .shorthelp = SHORTHELP                            \
-        };                                                        \
-        const struct futil_cmd_t * const __cmd_ptr_##NAME         \
-        __attribute__((section(".futil_cmds." #NAME)))            \
-          = &__cmd_##NAME
+        };
 
 /* This is the list of pointers to all commands. */
 extern const struct futil_cmd_t *const futil_cmds[];
diff --git a/futility/futility.lds b/futility/futility.lds
deleted file mode 100644
index 0650507f..00000000
--- a/futility/futility.lds
+++ /dev/null
@@ -1,15 +0,0 @@
-/*
- * Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-SECTIONS
-{
-  .rodata : {
-    . = ALIGN(32);
-    futil_cmds = .;                           /* Create the list of commands */
-    *(SORT(.futil_cmds.*));
-    QUAD(0);                                  /* Null-terminated */
-  }
-}