Undefined references due to varasm.c (globalize_decl) changes

[Danny Smith <danny_r_smith_2001 at yahoo dot co dot nz>]

This change;

2002-03-15  Jason Merrill  <jason@redhat.com>

	* varasm.c (globalize_decl): New fn.
	(assemble_start_function): Use it.
	(asm_emit_uninitialized): Use it.
	(assemble_alias): Use it.
	(assemble_variable): Use it.

cause problems with encoded stdcall function names on windows targets.


Before the patch, a stdcall function like:

void __attribute__((stdcall)) foo (int i)
{ (void)i;  return ;}

emitted this assembler output:

	.file	"foo.c"
	.text
	.align 2
.globl _foo@4
	.def	_foo@4;	.scl	2;	.type	32;	.endef
_foo@4:
	ret	$4


After the patch:

.globl _foo
	.def	_foo@4;	.scl	2;	.type	32;	.endef
_foo@4:
	ret	$4

globalize_decl uses IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl))
to get the label name, not the encoded name.  The @4 decoration is
generated by ENCODE_SECTION_INFO, calling gen_stdcall_suffix.

This caused undefined symbol _foo in object.

When building dlls (which disallow undefined symbols) ld cleverly
fixes up the reference to _foo by resolving to _foo@4, but issues a
warning, which normally should be taken seriously.

I have only tested the following fix, which passes the name as input
argument to globalize_decl, with mingw32,  I am not able to
test on other targets.  If this is not right, could someone please
point me to other ways to fix on windows targets.


ChangeLog

2002-13-18  Danny Smith <dannysmith@users.sourceforge.net>

	* varasm.c (globalize_decl): Get name as input parameter.
	(assemble_start_function): Update call to globalize_decl.
	(asm_emit_uninitialised): Likewise. 
	(assemble_alias): Likewise,.
	(assemble_variable): Likewise.



--- varasm.c.ori	Mon Mar 18 21:10:29 2002
+++ varasm.c	Tue Mar 19 08:26:31 2002
@@ -166,7 +166,7 @@ static unsigned HOST_WIDE_INT array_size
 static unsigned min_align		PARAMS ((unsigned, unsigned));
 static void output_constructor		PARAMS ((tree, HOST_WIDE_INT,
 						 unsigned int));
-static void globalize_decl		PARAMS ((tree));
+static void globalize_decl		PARAMS ((tree, const char *));
 static int in_named_entry_eq		PARAMS ((const PTR, const PTR));
 static hashval_t in_named_entry_hash	PARAMS ((const PTR));
 #ifdef ASM_OUTPUT_BSS
@@ -1235,7 +1235,7 @@ assemble_start_function (decl, fnname)
 	    weak_global_object_name = name;
 	}
 
-      globalize_decl (decl);
+      globalize_decl (decl, fnname);
     }
 
   /* Do any machine/system dependent processing of the function name */
@@ -1400,7 +1400,7 @@ asm_emit_uninitialised (decl, name, size
       if (! DECL_WEAK (decl))
 	break;
     case asm_dest_bss:
-      globalize_decl (decl);
+      globalize_decl (decl, name);
     default:
       break;
     }
@@ -1641,7 +1641,7 @@ assemble_variable (decl, top_level, at_e
 
   /* First make the assembler name(s) global if appropriate.  */
   if (TREE_PUBLIC (decl) && DECL_NAME (decl))
-    globalize_decl (decl);
+    globalize_decl (decl, name);
 
   /* Output any data that we will need to use the address of.  */
   if (DECL_INITIAL (decl) == error_mark_node)
@@ -5049,11 +5049,10 @@ weak_finish ()
 /* Emit the assembly bits to indicate that DECL is globally visible.  */
 
 static void
-globalize_decl (decl)
+globalize_decl (decl, name)
      tree decl;
+     const char * name;	
 {
-  const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
-
 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
   if (DECL_WEAK (decl))
     {
@@ -5098,7 +5097,7 @@ assemble_alias (decl, target)
 #ifdef ASM_OUTPUT_DEF
   /* Make name accessible from other files, if appropriate.  */
   if (TREE_PUBLIC (decl))
-    globalize_decl (decl);
+    globalize_decl (decl, name);
 
 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
   ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);

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