gcc 2.95.4 fix (fwd)

[Adrian Bunk <bunk@fs.tum.de>]

Hi,

I got this and the next mail I'll forward from Jack (I'm not sure if he
did also send them to you).

cu
Adrian


---------- Forwarded message ----------
Date: Tue, 1 May 2001 22:00:44 -0400 (EDT)
From: Jack Howarth <howarth@bromo.med.uc.edu>
To: bunk@fs.tum.de
Subject: gcc 2.95.4 fix

Hello,
    In case Franz Sirl hasn't passed this along, he has a work-around
for gcc 2.95.4 that allows glibc 2.2.3 to be built. Franz pointed me
to his bulk patch for gcc 2.95.4 that didn't have this fix parsed out
by itself however I believe this section is self-contained.

Index: gcc/varasm.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/varasm.c,v
retrieving revision 1.59.4.8
diff -u -p -r1.59.4.8 varasm.c
--- gcc/varasm.c        2001/03/28 09:02:17     1.59.4.8
+++ gcc/varasm.c        2001/05/01 17:11:28
@@ -118,6 +118,8 @@ struct constant_descriptor;
 struct rtx_const;
 struct pool_constant;

+void declare_weak PROTO ((tree));
+
 static const char *strip_reg_name      PROTO((const char *));
 static int contains_pointers_p         PROTO((tree));
 static void decode_addr_const          PROTO((tree, struct addr_const *));
@@ -143,6 +145,7 @@ static int output_addressed_constants       PR
 static void output_after_function_constants PROTO((void));
 static void output_constructor         PROTO((tree, int));
 static void remove_from_pending_weak_list      PROTO ((char *));
+static int is_on_pending_weak_list     PROTO ((char *));
 #ifdef ASM_OUTPUT_BSS
 static void asm_output_bss             PROTO((FILE *, tree, char *, int, int));
 #endif
@@ -755,6 +758,9 @@ make_decl_rtl (decl, asmspec, top_level)
          DECL_RTL (decl) = gen_rtx_MEM (DECL_MODE (decl),
                                         gen_rtx_SYMBOL_REF (Pmode, name));
          MEM_ALIAS_SET (DECL_RTL (decl)) = get_alias_set (decl);
+         if (is_on_pending_weak_list (name))
+           declare_weak (decl);
+         SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = DECL_WEAK (decl);


          /* If this variable is to be treated as volatile, show its
             tree node has side effects.  If it has side effects, either
@@ -4344,8 +4350,15 @@ declare_weak (decl)
 {
   if (! TREE_PUBLIC (decl))
     error_with_decl (decl, "weak declaration of `%s' must be public");
+#if 0
+  /* Due to a bug this error was never active, enabling it now would break
+   glibc.  */
   else if (TREE_ASM_WRITTEN (decl))
     error_with_decl (decl, "weak declaration of `%s' must precede definition");
+  /* This would be a new error, but it would break glibc too :-(.  */
+  else if (TREE_USED (decl))
+    error_with_decl (decl, "weak declaration of `%s' must precede its uses");
+#endif
   else if (SUPPORTS_WEAK)
     DECL_WEAK (decl) = 1;
 #ifdef HANDLE_PRAGMA_WEAK
@@ -4397,6 +4410,24 @@ remove_from_pending_weak_list (name)
        }
     }
 #endif
+}
+
+static int
+is_on_pending_weak_list (name)
+     char *name;
+{
+#ifdef HANDLE_PRAGMA_WEAK
+  if (HANDLE_PRAGMA_WEAK)
+    {
+      struct weak_syms *t;
+      for (t = weak_decls; t; t = t->next)
+       {
+         if (t->name && strcmp (name, t->name) == 0)
+           return 1;
+       }
+    }
+#endif
+  return 0;
 }

 void

You can check with Franz Sirl <Franz.Sirl-kernel@lauterbach.com>
if you have any questions on the hack but I know this works
ppc for building glibc 2.2.3. Please do let me know if you apply
this patch to any test packages of gcc 2.95.4 so I can build them
on ppc and try them out.
           Jack Howarth