configure.ac: Check for COMDAT support.

	* configure.ac: Check for COMDAT support.  Robustify check for
	SHF_MERGE support.
	* configure: Regenerated.
	* config.in: Likewise.
	* langhooks-def.h (lhd_comdat_group): New function.
	(LANG_HOOKS_COMDAT_GROUP): New macro.
	(LANG_HOOKS_DECLS): Use it.
	* langhooks.c (lhd_comdat_group): Define.
	* langhooks.h (lang_hooks_for_decls): Add comdat_group.
	* output.h (named_section_flags): Make it a macro.
	(named_section_real): New function.
	(default_no_named_section): Add decl parameter.
	(default_elf_asm_named_section): Likewise.
	(default_coff_asm_named_section): Likewise.
	(default_pe_asm_named_section): Likewise.
	* target.h (gcc_target): Adjust type of named_section.
	* varasm.c (named_section_flags): Rename to named_section_real.
	Add decl parameter.
	(default_no_named_section): Add decl parameter.
	(default_elf_asm_named_section): Use COMDAT, if available.  Deal
	with the case that ASM_COMMENT_START is "@".
	(default_coff_asm_named_section): Add decl parameter.
	(default_pe_asm_named_section): Likewise.
	* config/alpha/alpha.c (vms_asm_named_section): Add decl
	parameter.
	(unicosmk_asm_named_section): Likewise.
	* config/arm/arm.c (arm_elf_asm_named_section): Remove.
	* config/arm/elf.h (TARGET_ASM_NAMED_SECTION): Likewise.
	* config/c4x/c4x.c (c4x_asm_named_section): Add decl parameter.
	* config/cris/cris-protos.h (cris_target_asm_named_section):
	Likewise.
	* config/cris/cris.c (cris_target_asm_named_section):
	Likewise.
	* config/h8300/h8300.c (h8300_asm_named_section): Likewise.
	* config/i386/i386-protos.h (i386_pe_asm_named_section):
	Likewise.
	* config/i386/winnt.c (i386_pe_asm_named_section): Likewise.
	* config/m68k/m68k.c (m68k_coff_asm_named_section): Likewise.
	* config/mcore/mcore.c (mcore_asm_named_section): Likewise.
	* config/rs6000/rs6000.c (rs6000_xcoff_asm_named_section):
	Likewise.
	* config/sparc/sparc.c (sparce_elf_asm_named_section): Likewise.

	* cp-objcp-common.h (LANG_HOOKS_COMDAT_GROUP): Define.
	* cp-tree.h (cxx_comdat_group): Declare.
	* decl.c (cxx_comdat_group): New function.

From-SVN: r87557

4 files changed, 29 insertions, 0 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index f886a1e..2be3707 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2004-09-15  Mark Mitchell  <mark@codesourcery.com>
+
+	* cp-objcp-common.h (LANG_HOOKS_COMDAT_GROUP): Define.
+	* cp-tree.h (cxx_comdat_group): Declare.
+	* decl.c (cxx_comdat_group): New function.
+
 2004-09-15  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* search.c (get_pure_virtuals): Remove unused variables.
diff --git a/gcc/cp/cp-objcp-common.h b/gcc/cp/cp-objcp-common.h
index 1599080..a6ab383 100644
--- a/gcc/cp/cp-objcp-common.h
+++ b/gcc/cp/cp-objcp-common.h
@@ -92,6 +92,8 @@ extern tree objcp_tsubst_copy_and_build (tree, tree, tsubst_flags_t,
 #define LANG_HOOKS_WARN_UNUSED_GLOBAL_DECL cxx_warn_unused_global_decl
 #undef LANG_HOOKS_WRITE_GLOBALS
 #define LANG_HOOKS_WRITE_GLOBALS lhd_do_nothing
+#undef LANG_HOOKS_COMDAT_GROUP
+#define LANG_HOOKS_COMDAT_GROUP cxx_comdat_group
 
 #undef LANG_HOOKS_FUNCTION_INIT
 #define LANG_HOOKS_FUNCTION_INIT cxx_push_function_context
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 5d788af..22ac165 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -3789,6 +3789,7 @@ extern tree builtin_function (const char *name, tree type,
 			      const char *libname, tree attrs);
 extern tree check_elaborated_type_specifier     (enum tag_types, tree, bool);
 extern void warn_extern_redeclared_static (tree, tree);
+extern const char *cxx_comdat_group             (tree);
 extern bool cp_missing_noreturn_ok_p		(tree);
 extern void initialize_artificial_var            (tree, tree);
 
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 6128598..e56023b 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -10883,4 +10883,24 @@ cp_missing_noreturn_ok_p (tree decl)
   return DECL_MAIN_P (decl);
 }
 
+/* Return the COMDAT group into which DECL should be placed.  */
+
+const char *
+cxx_comdat_group (tree decl)
+{
+  tree name;
+
+  /* Virtual tables, construction virtual tables, and virtual table
+     tables all go in a single COMDAT group, named after the primary
+     virtual table.  */
+  if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl))
+    name = DECL_ASSEMBLER_NAME (CLASSTYPE_VTABLES (DECL_CONTEXT (decl)));
+  /* For all other DECLs, the COMDAT group is the mangled name of the
+     declaration itself.  */
+  else
+    name = DECL_ASSEMBLER_NAME (decl);
+
+  return IDENTIFIER_POINTER (name);
+}
+
 #include "gt-cp-decl.h"