Enabled linkonce support for Darwin.

	* target.h (struct gcc_target): New target hook, unwind_label.
	* target-def.h (TARGET_ASM_EMIT_UNWIND_LABEL): New hook.
	* output.h (default_emit_unwind_label): New function.
	* default.h (TARGET_EXPLICIT_INSTANTIATIONS_ONE_ONLY): New macro.
	(TARGET_USES_WEAK_UNWIND_INFO): New target macro.
	(TARGET_SUPPORTS_HIDDEN): New target macro.
	* dwarf2out.c (struct dw_fde_struct): Add field for function decl
	that corresponds to this FDE.
	(FRAME_BEGIN_LABEL): Allow target to override default label.
	(output_call_frame_info): If FDEs are linknonce, then use extra
	indirection for FDE encoding, output a label for each FDE, and
	output an empty label for each function without an FDE.
	(dwarf2out_begin_prologue): Set up decl field when creating an FDE.
	* varasm.c (globalize_decl): Call ASM_MAKE_LABEL_LINKONCE for
	decls with DECL_ONE_ONLY set, if that macro is defined.
	(make_decl_one_only): Don't use DECL_COMMON if we're compiling
	for a SUPPORTS_ONE_ONLY target.
	* config/darwin-protos.h (darwin_unique_section): Declare.
	(darwin_asm_named_section): Likewise.
	(darwin_section_type_flags): Likewise.
	(darwin_non_lazy_pcrel): Likewise.
	(darwin_emit_unwind_label): Likewise.
	(darwin_make_decl_one_only): Likewise.
	* config/darwin.c (machopic_finish): Get rid of tweak that
	eliminate stubs for symbols that are defined.
	(darwin_encode_section_info): Don't treat weak functions as defined.
	(darwin_make_decl_one_only): Define.
	(darwin_asm_named_section): Likewise.
	(darwin_section_type_flags): Likewise.
	(darwin_unique_section): Likewise.
	(darwin_emit_unwind_label): Likewise.
	(darwin_non_lazy_pcrel): Likewise.
	(darwin_asm_output_dwarf_delta): Difference between two labels is
	local only if both labels are local.
	* config/darwin.h (MAKE_DECL_ONE_ONLY): Define.
	(ASM_MAKE_LABEL_LINKONCE): Likewise.
	(TARGET_SUPPORTS_HIDDEN): Likewise.
	(TARGET_USES_WEAK_UNWIND_INFO): Likewise.
	(TARGET_EXPLICIT_INSTANTIATIONS_ONE_ONLY): Likewise.
	(FRAME_BEGIN_LABEL): Likewise.
	(ASM_DECLARE_OBJECT_NAME): Make references to weak symbols indirect.
	(ASM_DECLARE_FUNCTION_NAME): Likewise.
	(darwin_eh_frame_section): Give __eh_frame section the coalesced flag.
	(TARGET_ASM_UNIQUE_SECTION): Define.
	(EH_FRAME_SECTION_NAME): Define.
	(EH_FRAME_SECTION_ATTR): Likewise.
	(ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX): Likewise.
	(TARGET_ASM_NAMED_SECTION): Likewise.
	(TARGET_SECTION_TYPE_FLAGS): Likewise.
	* doc/tm.texi: Document TARGET_USES_WEAK_UNWIND_INFO,
	TARGET_EXPLICIT_INSTANTIATIONS_ONE_ONLY, TARGET_SUPPORTS_HIDDEN,
	TARGET_ASM_EMIT_UNWIND_LABEL.

	* cp/decl2.c (maybe_make_one_only): Look at
	TARGET_EXPLICIT_INSTANTIATION_ONE_ONLY when deciding whether
	to make an explicit instantiation weak.
	* cp/method.c (use_thunk): Make sure we call comdat_linkage
	when appropriate.
	* cp/pt.c (do_type_instantiation): On systems where weak symbols
	don't go in a static archive's TOC, explicit instantiation of a
	class must imply *explicit* instantiation of its memeber.

From-SVN: r79394

1 files changed, 17 insertions, 4 deletions

diff --git a/gcc/varasm.c b/gcc/varasm.c
index 061cbca..6a32ccc 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -4104,6 +4104,9 @@ globalize_decl (tree decl)
 	}
       return;
     }
+#elif defined(ASM_MAKE_LABEL_LINKONCE)
+  if (DECL_ONE_ONLY (decl))
+    ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
 #endif
 
   (*targetm.asm_out.globalize_label) (asm_out_file, name);
@@ -4228,16 +4231,16 @@ make_decl_one_only (tree decl)
 
   TREE_PUBLIC (decl) = 1;
 
-  if (TREE_CODE (decl) == VAR_DECL
-      && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
-    DECL_COMMON (decl) = 1;
-  else if (SUPPORTS_ONE_ONLY)
+  if (SUPPORTS_ONE_ONLY)
     {
 #ifdef MAKE_DECL_ONE_ONLY
       MAKE_DECL_ONE_ONLY (decl);
 #endif
       DECL_ONE_ONLY (decl) = 1;
     }
+  else if (TREE_CODE (decl) == VAR_DECL
+      && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
+    DECL_COMMON (decl) = 1;
   else if (SUPPORTS_WEAK)
     DECL_WEAK (decl) = 1;
   else
@@ -4917,6 +4920,16 @@ default_globalize_label (FILE * stream, const char *name)
 }
 #endif /* GLOBAL_ASM_OP */
 
+/* Default function to output a label for unwind information.  The
+   default is to do nothing.  A target that needs nonlocal labels for
+   unwind information must provide its own function to do this. */
+void
+default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
+			   tree decl ATTRIBUTE_UNUSED,
+			   int empty ATTRIBUTE_UNUSED)
+{ 
+}
+
 /* This is how to output an internal numbered label where PREFIX is
    the class of label and LABELNO is the number within the class.  */