Constify the tool interface.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14642 a5019735-40e9-0310-863c-91ae7b9d1cf9

12 files changed, 113 insertions, 109 deletions

diff --git a/coregrind/m_errormgr.c b/coregrind/m_errormgr.c
index c2f844c53..6cbc31e90 100644
--- a/coregrind/m_errormgr.c
+++ b/coregrind/m_errormgr.c
@@ -147,27 +147,27 @@ struct _Error {
 };
 
 
-ExeContext* VG_(get_error_where) ( Error* err )
+ExeContext* VG_(get_error_where) ( const Error* err )
 {
    return err->where;
 }
 
-ErrorKind VG_(get_error_kind) ( Error* err )
+ErrorKind VG_(get_error_kind) ( const Error* err )
 {
    return err->ekind;
 }
 
-Addr VG_(get_error_address) ( Error* err )
+Addr VG_(get_error_address) ( const Error* err )
 {
    return err->addr;
 }
 
-const HChar* VG_(get_error_string) ( Error* err )
+const HChar* VG_(get_error_string) ( const Error* err )
 {
    return err->string;
 }
 
-void* VG_(get_error_extra)  ( Error* err )
+void* VG_(get_error_extra)  ( const Error* err )
 {
    return err->extra;
 }
@@ -246,17 +246,17 @@ struct _Supp {
    void* extra;      // Anything else -- use is optional.  NULL by default.
 };
 
-SuppKind VG_(get_supp_kind) ( Supp* su )
+SuppKind VG_(get_supp_kind) ( const Supp* su )
 {
    return su->skind;
 }
 
-HChar* VG_(get_supp_string) ( Supp* su )
+HChar* VG_(get_supp_string) ( const Supp* su )
 {
    return su->string;
 }
 
-void* VG_(get_supp_extra)  ( Supp* su )
+void* VG_(get_supp_extra)  ( const Supp* su )
 {
    return su->extra;
 }
diff --git a/coregrind/m_tooliface.c b/coregrind/m_tooliface.c
index e96a9a136..3fd8f821d 100644
--- a/coregrind/m_tooliface.c
+++ b/coregrind/m_tooliface.c
@@ -227,18 +227,18 @@ void VG_(needs_superblock_discards)(
 }
 
 void VG_(needs_tool_errors)(
-   Bool (*eq)         (VgRes, Error*, Error*),
-   void (*before_pp)  (Error*),
-   void (*pp)         (Error*),
+   Bool (*eq)         (VgRes, const Error*, const Error*),
+   void (*before_pp)  (const Error*),
+   void (*pp)         (const Error*),
    Bool show_TIDs,
-   UInt (*update)     (Error*),
+   UInt (*update)     (const Error*),
    Bool (*recog)      (const HChar*, Supp*),
    Bool (*read_extra) (Int, HChar**, SizeT*, Int*, Supp*),
-   Bool (*matches)    (Error*, Supp*),
-   const HChar* (*name) (Error*),
-   SizeT (*get_xtra_si)(Error*,/*OUT*/HChar*,Int),
-   SizeT (*print_xtra_su)(Supp*,/*OUT*/HChar*,Int),
-   void (*update_xtra_su)(Error*, Supp*)
+   Bool (*matches)    (const Error*, const Supp*),
+   const HChar* (*name) (const Error*),
+   SizeT (*get_xtra_si)(const Error*,/*OUT*/HChar*,Int),
+   SizeT (*print_xtra_su)(const Supp*,/*OUT*/HChar*,Int),
+   void (*update_xtra_su)(const Error*, const Supp*)
 )
 {
    VG_(needs).tool_errors = True;
diff --git a/coregrind/pub_core_tooliface.h b/coregrind/pub_core_tooliface.h
index 585170be0..9b7df351e 100644
--- a/coregrind/pub_core_tooliface.h
+++ b/coregrind/pub_core_tooliface.h
@@ -118,19 +118,19 @@ typedef struct {
    // (none)
    
    // VG_(needs).tool_errors
-   Bool  (*tool_eq_Error)                    (VgRes, Error*, Error*);
-   void  (*tool_before_pp_Error)             (Error*);
-   void  (*tool_pp_Error)                    (Error*);
+   Bool  (*tool_eq_Error)                  (VgRes, const Error*, const Error*);
+   void  (*tool_before_pp_Error)           (const Error*);
+   void  (*tool_pp_Error)                  (const Error*);
    Bool  tool_show_ThreadIDs_for_errors;
-   UInt  (*tool_update_extra)                (Error*);
+   UInt  (*tool_update_extra)                (const Error*);
    Bool  (*tool_recognised_suppression)      (const HChar*, Supp*);
    Bool  (*tool_read_extra_suppression_info) (Int, HChar**, SizeT*, Int*,
                                               Supp*);
-   Bool  (*tool_error_matches_suppression)   (Error*, Supp*);
-   const HChar* (*tool_get_error_name)       (Error*);
-   SizeT (*tool_get_extra_suppression_info)  (Error*,/*OUT*/HChar*,Int);
-   SizeT (*tool_print_extra_suppression_use) (Supp*,/*OUT*/HChar*,Int);
-   void  (*tool_update_extra_suppression_use) (Error*, Supp*);
+   Bool  (*tool_error_matches_suppression)   (const Error*, const Supp*);
+   const HChar* (*tool_get_error_name)       (const Error*);
+   SizeT (*tool_get_extra_suppression_info)  (const Error*,/*OUT*/HChar*,Int);
+   SizeT (*tool_print_extra_suppression_use) (const Supp*,/*OUT*/HChar*,Int);
+   void  (*tool_update_extra_suppression_use) (const Error*, const Supp*);
 
    // VG_(needs).superblock_discards
    void (*tool_discard_superblock_info)(Addr64, VexGuestExtents);
diff --git a/drd/drd_error.c b/drd/drd_error.c
index 1d8f0e35c..e3df0b59a 100644
--- a/drd/drd_error.c
+++ b/drd/drd_error.c
@@ -43,7 +43,7 @@
 
 /* Local function declarations. */
 
-static const HChar* drd_get_error_name(Error* e);
+static const HChar* drd_get_error_name(const Error* e);
 
 
 /* Local variables. */
@@ -151,7 +151,8 @@ static void first_observed(const Addr obj)
 }
 
 static
-void drd_report_data_race(Error* const err, const DataRaceErrInfo* const dri)
+void drd_report_data_race(const Error* const err,
+                          const DataRaceErrInfo* const dri)
 {
    const Bool xml = VG_(clo_xml);
    const HChar* const what_prefix = xml ? "  <what>" : "";
@@ -254,7 +255,8 @@ void drd_report_data_race(Error* const err, const DataRaceErrInfo* const dri)
  * if the error kind of e1 and e2 matches and if the ExeContext's of e1 and
  * e2 also match.
  */
-static Bool drd_compare_error_contexts(VgRes res, Error* e1, Error* e2)
+static Bool drd_compare_error_contexts(VgRes res, const Error* e1,
+                                       const Error* e2)
 {
    tl_assert(VG_(get_error_kind)(e1) == VG_(get_error_kind)(e2));
 
@@ -282,7 +284,7 @@ static Bool drd_compare_error_contexts(VgRes res, Error* e1, Error* e2)
  * Called by the core just before an error message will be printed. Used by
  * DRD to print the thread number as a preamble.
  */
-static void drd_tool_error_before_pp(Error* const e)
+static void drd_tool_error_before_pp(const Error* const e)
 {
    static DrdThreadId s_last_tid_printed = 1;
    DrdThreadId* err_extra;
@@ -296,7 +298,7 @@ static void drd_tool_error_before_pp(Error* const e)
 }
 
 /** Report an error to the user. */
-static void drd_tool_error_pp(Error* const e)
+static void drd_tool_error_pp(const Error* const e)
 {
    const Bool xml = VG_(clo_xml);
    const HChar* const what_prefix = xml ? "  <what>" : "";
@@ -460,7 +462,7 @@ static void drd_tool_error_pp(Error* const e)
    }
 }
 
-static UInt drd_tool_error_update_extra(Error* e)
+static UInt drd_tool_error_update_extra(const Error* e)
 {
    switch (VG_(get_error_kind)(e))
    {
@@ -563,12 +565,13 @@ Bool drd_read_extra_suppression_info(Int fd, HChar** bufpp,
  * Determine whether or not the types of the given error message and the
  * given suppression match.
  */
-static Bool drd_error_matches_suppression(Error* const e, Supp* const supp)
+static Bool drd_error_matches_suppression(const Error* const e,
+                                          const Supp* const supp)
 {
    return VG_(get_supp_kind)(supp) == VG_(get_error_kind)(e);
 }
 
-static const HChar* drd_get_error_name(Error* e)
+static const HChar* drd_get_error_name(const Error* e)
 {
    switch (VG_(get_error_kind)(e))
    {
@@ -600,7 +603,7 @@ static const HChar* drd_get_error_name(Error* e)
  * define any 'extra' suppression information.
  */
 static
-SizeT drd_get_extra_suppression_info(Error* e,
+SizeT drd_get_extra_suppression_info(const Error* e,
                                      /*OUT*/HChar* buf, Int nBuf)
 {
    tl_assert(nBuf >= 1);
@@ -609,7 +612,7 @@ SizeT drd_get_extra_suppression_info(Error* e,
 }
 
 static
-SizeT drd_print_extra_suppression_use(Supp* su,
+SizeT drd_print_extra_suppression_use(const Supp* su,
                                       /*OUT*/HChar* buf, Int nBuf)
 {
    tl_assert(nBuf >= 1);
@@ -618,7 +621,7 @@ SizeT drd_print_extra_suppression_use(Supp* su,
 }
 
 static
-void  drd_update_extra_suppresion_use(Error* e, Supp* supp)
+void  drd_update_extra_suppresion_use(const Error* e, const Supp* supp)
 {
    return;
 }
diff --git a/exp-sgcheck/pc_common.c b/exp-sgcheck/pc_common.c
index 27dd2f217..042a86077 100644
--- a/exp-sgcheck/pc_common.c
+++ b/exp-sgcheck/pc_common.c
@@ -216,7 +216,7 @@ void h_record_sysparam_error( ThreadId tid, CorePart part, const HChar* s,
 }
 
 
-Bool pc_eq_Error ( VgRes res, Error* e1, Error* e2 )
+Bool pc_eq_Error ( VgRes res, const Error* e1, const Error* e2 )
 {
    XError *xe1, *xe2;
    tl_assert(VG_(get_error_kind)(e1) == VG_(get_error_kind)(e2));
@@ -262,7 +262,7 @@ Bool pc_eq_Error ( VgRes res, Error* e1, Error* e2 )
    look at it any print any preamble you want" function.  Which, in
    Ptrcheck, we don't use.  Hence a no-op.
 */
-void pc_before_pp_Error ( Error* err ) {
+void pc_before_pp_Error ( const Error* err ) {
 }
 
 /* Do a printf-style operation on either the XML or normal output
@@ -302,7 +302,7 @@ static Word Word__abs ( Word w ) {
    return w < 0 ? -w : w;
 }
 
-void pc_pp_Error ( Error* err )
+void pc_pp_Error ( const Error* err )
 {
    const Bool xml = VG_(clo_xml); /* a shorthand, that's all */
 
@@ -647,7 +647,7 @@ void pc_pp_Error ( Error* err )
 }
 
 
-UInt pc_update_Error_extra ( Error* err )
+UInt pc_update_Error_extra ( const Error* err )
 {
    XError *xe = (XError*)VG_(get_error_extra)(err);
    tl_assert(xe);
@@ -736,7 +736,8 @@ Bool pc_is_recognised_suppression ( const HChar* name, Supp *su )
 }
 
 Bool pc_read_extra_suppression_info ( Int fd, HChar** bufpp, 
-                                      SizeT* nBufp, Int* lineno, Supp* su )
+                                      SizeT* nBufp, Int* lineno,
+                                      Supp* su )
 {
    Bool eof;
    if (VG_(get_supp_kind)(su) == XS_SysParam) {
@@ -747,7 +748,7 @@ Bool pc_read_extra_suppression_info ( Int fd, HChar** bufpp,
    return True;
 }
 
-Bool pc_error_matches_suppression (Error* err, Supp* su)
+Bool pc_error_matches_suppression (const Error* err, const Supp* su)
 {
    ErrorKind ekind = VG_(get_error_kind)(err);
    switch (VG_(get_supp_kind)(su)) {
@@ -764,7 +765,7 @@ Bool pc_error_matches_suppression (Error* err, Supp* su)
    }
 }
 
-const HChar* pc_get_error_name ( Error* err )
+const HChar* pc_get_error_name ( const Error* err )
 {
    XError *xe = (XError*)VG_(get_error_extra)(err);
    tl_assert(xe);
@@ -777,7 +778,7 @@ const HChar* pc_get_error_name ( Error* err )
    }
 }
 
-SizeT pc_get_extra_suppression_info ( Error* err,
+SizeT pc_get_extra_suppression_info ( const Error* err,
                                       /*OUT*/HChar* buf, Int nBuf )
 {
    ErrorKind ekind = VG_(get_error_kind )(err);
@@ -794,7 +795,7 @@ SizeT pc_get_extra_suppression_info ( Error* err,
    }
 }
 
-SizeT pc_print_extra_suppression_use ( Supp* su,
+SizeT pc_print_extra_suppression_use ( const Supp* su,
                                        /*OUT*/HChar* buf, Int nBuf )
 {
    tl_assert(nBuf >= 1);
@@ -802,7 +803,7 @@ SizeT pc_print_extra_suppression_use ( Supp* su,
    return 0;
 }
 
-void pc_update_extra_suppression_use (Error* err, Supp* su)
+void pc_update_extra_suppression_use (const Error* err, const Supp* su)
 {
    return;
 }
diff --git a/exp-sgcheck/pc_common.h b/exp-sgcheck/pc_common.h
index f0d3a86dd..932e850dc 100644
--- a/exp-sgcheck/pc_common.h
+++ b/exp-sgcheck/pc_common.h
@@ -47,20 +47,20 @@ void h_record_arith_error( Seg* seg1, Seg* seg2, HChar* opname );
 void h_record_sysparam_error( ThreadId tid, CorePart part, const HChar* s,
                               Addr lo, Addr hi, Seg* seglo, Seg* seghi );
 
-Bool pc_eq_Error           ( VgRes res, Error* e1, Error* e2 );
-void pc_before_pp_Error    ( Error* err );
-void pc_pp_Error           ( Error* err );
-UInt pc_update_Error_extra ( Error* err );
+Bool pc_eq_Error           ( VgRes res, const Error* e1, const Error* e2 );
+void pc_before_pp_Error    ( const Error* err );
+void pc_pp_Error           ( const Error* err );
+UInt pc_update_Error_extra ( const Error* err );
 Bool pc_is_recognised_suppression ( const HChar* name, Supp *su );
 Bool pc_read_extra_suppression_info ( Int fd, HChar** bufpp, 
                                       SizeT* nBufp, Int* lineno, Supp* su );
-Bool pc_error_matches_suppression (Error* err, Supp* su);
-const HChar* pc_get_error_name ( Error* err );
-SizeT pc_get_extra_suppression_info ( Error* err,
+Bool pc_error_matches_suppression (const Error* err, const Supp* su);
+const HChar* pc_get_error_name ( const Error* err );
+SizeT pc_get_extra_suppression_info ( const Error* err,
                                      /*OUT*/HChar* buf, Int nBuf );
-SizeT pc_print_extra_suppression_use ( Supp* su,
+SizeT pc_print_extra_suppression_use ( const Supp* su,
                                       /*OUT*/HChar* buf, Int nBuf );
-void pc_update_extra_suppression_use (Error* err, Supp* su);
+void pc_update_extra_suppression_use (const Error* err, const Supp* su);
 
 extern Bool h_clo_partial_loads_ok;
 /* extern Bool h_clo_lossage_check; */
diff --git a/helgrind/hg_errors.c b/helgrind/hg_errors.c
index fc33bedc2..0e96d7e76 100644
--- a/helgrind/hg_errors.c
+++ b/helgrind/hg_errors.c
@@ -371,7 +371,7 @@ typedef
 
 
 /* Updates the copy with address info if necessary. */
-UInt HG_(update_extra) ( Error* err )
+UInt HG_(update_extra) ( const Error* err )
 {
    XError* xe = (XError*)VG_(get_error_extra)(err);
    tl_assert(xe);
@@ -637,7 +637,7 @@ void HG_(record_error_Misc) ( Thread* thr, const HChar* errstr )
    HG_(record_error_Misc_w_aux)(thr, errstr, NULL, NULL);
 }
 
-Bool HG_(eq_Error) ( VgRes not_used, Error* e1, Error* e2 )
+Bool HG_(eq_Error) ( VgRes not_used, const Error* e1, const Error* e2 )
 {
    XError *xe1, *xe2;
 
@@ -843,7 +843,7 @@ static void show_LockP_summary_textmode ( Lock** locks, const HChar* pre )
    announce any previously un-announced threads in the upcoming error
    message.
 */
-void HG_(before_pp_Error) ( Error* err )
+void HG_(before_pp_Error) ( const Error* err )
 {
    XError* xe;
    tl_assert(err);
@@ -893,7 +893,7 @@ void HG_(before_pp_Error) ( Error* err )
    }
 }
 
-void HG_(pp_Error) ( Error* err )
+void HG_(pp_Error) ( const Error* err )
 {
    const Bool xml = VG_(clo_xml); /* a shorthand, that's all */
 
@@ -1252,7 +1252,7 @@ void HG_(pp_Error) ( Error* err )
    } /* switch (VG_(get_error_kind)(err)) */
 }
 
-const HChar* HG_(get_error_name) ( Error* err )
+const HChar* HG_(get_error_name) ( const Error* err )
 {
    switch (VG_(get_error_kind)(err)) {
       case XE_Race:           return "Race";
@@ -1293,7 +1293,7 @@ Bool HG_(read_extra_suppression_info) ( Int fd, HChar** bufpp, SizeT* nBufp,
    return True;
 }
 
-Bool HG_(error_matches_suppression) ( Error* err, Supp* su )
+Bool HG_(error_matches_suppression) ( const Error* err, const Supp* su )
 {
    switch (VG_(get_supp_kind)(su)) {
    case XS_Race:           return VG_(get_error_kind)(err) == XE_Race;
@@ -1308,7 +1308,7 @@ Bool HG_(error_matches_suppression) ( Error* err, Supp* su )
    }
 }
 
-SizeT HG_(get_extra_suppression_info) ( Error* err,
+SizeT HG_(get_extra_suppression_info) ( const Error* err,
                                        /*OUT*/HChar* buf, Int nBuf )
 {
    tl_assert(nBuf >= 1);
@@ -1317,7 +1317,7 @@ SizeT HG_(get_extra_suppression_info) ( Error* err,
    return 0;
 }
 
-SizeT HG_(print_extra_suppression_use) ( Supp* su,
+SizeT HG_(print_extra_suppression_use) ( const Supp* su,
                                         /*OUT*/HChar* buf, Int nBuf )
 {
    tl_assert(nBuf >= 1);
@@ -1326,7 +1326,7 @@ SizeT HG_(print_extra_suppression_use) ( Supp* su,
    return 0;
 }
 
-void HG_(update_extra_suppression_use) ( Error* err, Supp* su )
+void HG_(update_extra_suppression_use) ( const Error* err, const Supp* su )
 {
    /* Do nothing */
    return;
diff --git a/helgrind/hg_errors.h b/helgrind/hg_errors.h
index 76f214593..e3d864317 100644
--- a/helgrind/hg_errors.h
+++ b/helgrind/hg_errors.h
@@ -35,20 +35,20 @@
 
 /* The standard bundle of error management functions that we are
 required to present to the core/tool interface at startup. */
-Bool  HG_(eq_Error)        ( VgRes not_used, Error* e1, Error* e2 );
-void  HG_(before_pp_Error) ( Error* err );
-void  HG_(pp_Error)        ( Error* err );
-UInt  HG_(update_extra)    ( Error* err );
+Bool  HG_(eq_Error)        ( VgRes not_used, const Error* e1, const Error* e2 );
+void  HG_(before_pp_Error) ( const Error* err );
+void  HG_(pp_Error)        ( const Error* err );
+UInt  HG_(update_extra)    ( const Error* err );
 Bool  HG_(recognised_suppression) ( const HChar* name, Supp *su );
 Bool  HG_(read_extra_suppression_info) ( Int fd, HChar** bufpp, SizeT* nBufp,
                                          Int* lineno, Supp* su );
-Bool  HG_(error_matches_suppression) ( Error* err, Supp* su );
-const HChar* HG_(get_error_name) ( Error* err );
-SizeT HG_(get_extra_suppression_info) ( Error* err,
+Bool  HG_(error_matches_suppression) ( const Error* err, const Supp* su );
+const HChar* HG_(get_error_name) ( const Error* err );
+SizeT HG_(get_extra_suppression_info) ( const Error* err,
                                         /*OUT*/HChar* buf, Int nBuf );
-SizeT HG_(print_extra_suppression_use) ( Supp* su,
+SizeT HG_(print_extra_suppression_use) ( const Supp* su,
                                          /*OUT*/HChar* buf, Int nBuf );
-void  HG_(update_extra_suppression_use) ( Error* err, Supp* su );
+void  HG_(update_extra_suppression_use) ( const Error* err, const Supp* su );
 
 /* Functions for recording various kinds of errors. */
 void HG_(record_error_Race) ( Thread* thr, 
diff --git a/include/pub_tool_errormgr.h b/include/pub_tool_errormgr.h
index 427c0f076..ad1f6b06b 100644
--- a/include/pub_tool_errormgr.h
+++ b/include/pub_tool_errormgr.h
@@ -56,11 +56,11 @@ typedef
 
 /* Useful in VG_(tdict).tool_error_matches_suppression(),
  * VG_(tdict).tool_pp_Error(), etc */
-ExeContext*  VG_(get_error_where)   ( Error* err );
-ErrorKind    VG_(get_error_kind)    ( Error* err );
-Addr         VG_(get_error_address) ( Error* err );
-const HChar* VG_(get_error_string)  ( Error* err );
-void*        VG_(get_error_extra)   ( Error* err );
+ExeContext*  VG_(get_error_where)   ( const Error* err );
+ErrorKind    VG_(get_error_kind)    ( const Error* err );
+Addr         VG_(get_error_address) ( const Error* err );
+const HChar* VG_(get_error_string)  ( const Error* err );
+void*        VG_(get_error_extra)   ( const Error* err );
 
 /* Call this when an error occurs.  It will be recorded if it hasn't been
    seen before.  If it has, the existing error record will have its count
@@ -127,9 +127,9 @@ typedef
    Supp;
 
 /* Useful in VG_(tdict).tool_error_matches_suppression() */
-SuppKind VG_(get_supp_kind)   ( Supp* su );
-HChar*   VG_(get_supp_string) ( Supp* su );
-void*    VG_(get_supp_extra)  ( Supp* su );
+SuppKind VG_(get_supp_kind)   ( const Supp* su );
+HChar*   VG_(get_supp_string) ( const Supp* su );
+void*    VG_(get_supp_extra)  ( const Supp* su );
 
 /* Must be used in VG_(recognised_suppression)() */
 void VG_(set_supp_kind)   ( Supp* su, SuppKind suppkind );
diff --git a/include/pub_tool_tooliface.h b/include/pub_tool_tooliface.h
index ad503b00e..6f84ca4e7 100644
--- a/include/pub_tool_tooliface.h
+++ b/include/pub_tool_tooliface.h
@@ -284,7 +284,7 @@ extern void VG_(needs_tool_errors) (
    // passed to VG_(eq_ExeContext)() if the ExeContexts are considered.  Other
    // than that, probably don't worry about it unless you have lots of very
    // similar errors occurring.
-   Bool (*eq_Error)(VgRes res, Error* e1, Error* e2),
+   Bool (*eq_Error)(VgRes res, const Error* e1, const Error* e2),
 
    // We give tools a chance to have a look at errors
    // just before they are printed.  That is, before_pp_Error is 
@@ -294,10 +294,10 @@ extern void VG_(needs_tool_errors) (
    // is printed.  This functionality was added to allow Helgrind to
    // print thread-announcement messages immediately before the 
    // errors that refer to them.
-   void (*before_pp_Error)(Error* err),
+   void (*before_pp_Error)(const Error* err),
 
    // Print error context.
-   void (*pp_Error)(Error* err),
+   void (*pp_Error)(const Error* err),
 
    // Should the core indicate which ThreadId each error comes from?
    Bool show_ThreadIDs_for_errors,
@@ -309,7 +309,7 @@ extern void VG_(needs_tool_errors) (
    // Yuk.
    // Return value: must be the size of the `extra' part in bytes -- used by
    // the core to make a copy.
-   UInt (*update_extra)(Error* err),
+   UInt (*update_extra)(const Error* err),
 
    // Return value indicates recognition.  If recognised, must set skind using
    // VG_(set_supp_kind)().
@@ -326,12 +326,12 @@ extern void VG_(needs_tool_errors) (
    // This should just check the kinds match and maybe some stuff in the
    // `string' and `extra' field if appropriate (using VG_(get_supp_*)() to
    // get the relevant suppression parts).
-   Bool (*error_matches_suppression)(Error* err, Supp* su),
+   Bool (*error_matches_suppression)(const Error* err, const Supp* su),
 
    // This should return the suppression name, for --gen-suppressions, or NULL
    // if that error type cannot be suppressed.  This is the inverse of
    // VG_(tdict).tool_recognised_suppression().
-   const HChar* (*get_error_name)(Error* err),
+   const HChar* (*get_error_name)(const Error* err),
 
    // This should print into buf[0..nBuf-1] any extra info for the
    // error, for --gen-suppressions, but not including any leading
@@ -340,13 +340,13 @@ extern void VG_(needs_tool_errors) (
    // including the terminating null character the function shall
    // return the value that strlen would return for the string.
    // If the buffer is too small the function shall return nBuf.
-   SizeT (*print_extra_suppression_info)(Error* err,
+   SizeT (*print_extra_suppression_info)(const Error* err,
                                          /*OUT*/HChar* buf, Int nBuf),
 
    // This is similar to print_extra_suppression_info, but is used
    // to print information such as additional statistical counters
    // as part of the used suppression list produced by -v.
-   SizeT (*print_extra_suppression_use)(Supp* su,
+   SizeT (*print_extra_suppression_use)(const Supp* su,
                                         /*OUT*/HChar* buf, Int nBuf),
 
    // Called by error mgr once it has been established that err
@@ -354,7 +354,7 @@ extern void VG_(needs_tool_errors) (
    // can be used to update suppression extra information such as
    // some statistical counters that will be printed by
    // print_extra_suppression_use.
-   void (*update_extra_suppression_use)(Error* err, Supp* su)
+   void (*update_extra_suppression_use)(const Error* err, const Supp* su)
 );
 
 /* Is information kept by the tool about specific instructions or
diff --git a/memcheck/mc_errors.c b/memcheck/mc_errors.c
index 1f031c623..3303ee1e0 100644
--- a/memcheck/mc_errors.c
+++ b/memcheck/mc_errors.c
@@ -200,7 +200,7 @@ struct _MC_Error {
    look at it any print any preamble you want" function.  Which, in
    Memcheck, we don't use.  Hence a no-op.
 */
-void MC_(before_pp_Error) ( Error* err ) {
+void MC_(before_pp_Error) ( const Error* err ) {
 }
 
 /* Do a printf-style operation on either the XML or normal output
@@ -410,7 +410,7 @@ void MC_(pp_LossRecord)(UInt n_this_record, UInt n_total_records,
    pp_LossRecord (n_this_record, n_total_records, l, /* xml */ False);
 }
 
-void MC_(pp_Error) ( Error* err )
+void MC_(pp_Error) ( const Error* err )
 {
    const Bool xml  = VG_(clo_xml); /* a shorthand */
    MC_Error* extra = VG_(get_error_extra)(err);
@@ -931,7 +931,7 @@ void MC_(record_user_error) ( ThreadId tid, Addr a,
 /* Compare error contexts, to detect duplicates.  Note that if they
    are otherwise the same, the faulting addrs and associated rwoffsets
    are allowed to be different.  */
-Bool MC_(eq_Error) ( VgRes res, Error* e1, Error* e2 )
+Bool MC_(eq_Error) ( VgRes res, const Error* e1, const Error* e2 )
 {
    MC_Error* extra1 = VG_(get_error_extra)(e1);
    MC_Error* extra2 = VG_(get_error_extra)(e2);
@@ -1100,7 +1100,7 @@ static void update_origin ( /*OUT*/ExeContext** origin_ec,
 }
 
 /* Updates the copy with address info if necessary (but not for all errors). */
-UInt MC_(update_Error_extra)( Error* err )
+UInt MC_(update_Error_extra)( const Error* err )
 {
    MC_Error* extra = VG_(get_error_extra)(err);
 
@@ -1386,7 +1386,7 @@ Bool MC_(read_extra_suppression_info) ( Int fd, HChar** bufpp,
    return True;
 }
 
-Bool MC_(error_matches_suppression) ( Error* err, Supp* su )
+Bool MC_(error_matches_suppression) ( const Error* err, const Supp* su )
 {
    Int       su_szB;
    MC_Error* extra = VG_(get_error_extra)(err);
@@ -1470,7 +1470,7 @@ Bool MC_(error_matches_suppression) ( Error* err, Supp* su )
    }
 }
 
-const HChar* MC_(get_error_name) ( Error* err )
+const HChar* MC_(get_error_name) ( const Error* err )
 {
    switch (VG_(get_error_kind)(err)) {
    case Err_RegParam:       return "Param";
@@ -1511,7 +1511,7 @@ const HChar* MC_(get_error_name) ( Error* err )
    }
 }
 
-SizeT MC_(get_extra_suppression_info) ( Error* err,
+SizeT MC_(get_extra_suppression_info) ( const Error* err,
                                         /*OUT*/HChar* buf, Int nBuf )
 {
    ErrorKind ekind = VG_(get_error_kind )(err);
@@ -1537,7 +1537,7 @@ SizeT MC_(get_extra_suppression_info) ( Error* err,
    }
 }
 
-SizeT MC_(print_extra_suppression_use) ( Supp *su,
+SizeT MC_(print_extra_suppression_use) ( const Supp *su,
                                          /*OUT*/HChar *buf, Int nBuf )
 {
    tl_assert(nBuf >= 1);
@@ -1558,7 +1558,7 @@ SizeT MC_(print_extra_suppression_use) ( Supp *su,
    return 0;
 }
 
-void MC_(update_extra_suppression_use) ( Error* err, Supp* su)
+void MC_(update_extra_suppression_use) ( const Error* err, const Supp* su)
 {
    if (VG_(get_supp_kind)(su) == LeakSupp) {
       MC_LeakSuppExtra *lse = (MC_LeakSuppExtra*) VG_(get_supp_extra) (su);
diff --git a/memcheck/mc_include.h b/memcheck/mc_include.h
index 51a36c2dc..f50a07940 100644
--- a/memcheck/mc_include.h
+++ b/memcheck/mc_include.h
@@ -393,25 +393,25 @@ extern Bool MC_(any_value_errors);
 
 /* Standard functions for error and suppressions as required by the
    core/tool iface */
-Bool MC_(eq_Error)           ( VgRes res, Error* e1, Error* e2 );
-void MC_(before_pp_Error)    ( Error* err );
-void MC_(pp_Error)           ( Error* err );
-UInt MC_(update_Error_extra) ( Error* err );
+Bool MC_(eq_Error)           ( VgRes res, const Error* e1, const Error* e2 );
+void MC_(before_pp_Error)    ( const Error* err );
+void MC_(pp_Error)           ( const Error* err );
+UInt MC_(update_Error_extra) ( const Error* err );
 
 Bool MC_(is_recognised_suppression) ( const HChar* name, Supp* su );
 
 Bool MC_(read_extra_suppression_info) ( Int fd, HChar** buf,
                                         SizeT* nBuf, Int* lineno, Supp *su );
 
-Bool MC_(error_matches_suppression) ( Error* err, Supp* su );
+Bool MC_(error_matches_suppression) ( const Error* err, const Supp* su );
 
-SizeT MC_(get_extra_suppression_info) ( Error* err,
+SizeT MC_(get_extra_suppression_info) ( const Error* err,
                                         /*OUT*/HChar* buf, Int nBuf );
-SizeT MC_(print_extra_suppression_use) ( Supp* su,
+SizeT MC_(print_extra_suppression_use) ( const Supp* su,
                                          /*OUT*/HChar* buf, Int nBuf );
-void MC_(update_extra_suppression_use) ( Error* err, Supp* su );
+void MC_(update_extra_suppression_use) ( const Error* err, const Supp* su );
 
-const HChar* MC_(get_error_name) ( Error* err );
+const HChar* MC_(get_error_name) ( const Error* err );
 
 /* Recording of errors */
 void MC_(record_address_error) ( ThreadId tid, Addr a, Int szB,