re PR debug/23190 (debug info omitted for uninitialized variables (stabs))

        PR debug/23190
        * toplev.c (wrapup_global_declaration_1): Split out ...
        (wrapup_global_declaration_2): ... from ...
        (wrapup_global_declarations): ... here.  Return bool.
        (check_global_declaration_1): Split out ...
        (check_global_declarations): from here.
        (emit_debug_global_declarations): New.
        * toplev.h (wrapup_global_declaration_1, wrapup_global_declaration_2,
        check_global_declaration_1, emit_debug_global_declarations): Declare.
        * c-decl.c (c_write_global_declarations_1): Don't create a vector
        of decls.  Call wrapup_global_declaration_1,
        wrapup_global_declaration_2, check_global_declaration_1 directly.
        (c_write_global_declarations_2): New.
        (ext_block): New.
        (c_write_global_declarations): Call c_write_global_declarations_2.
        * langhooks.c (write_global_declarations): Call
        emit_debug_global_declarations.
        * cgraphunit.c (cgraph_varpool_remove_unreferenced_decls): Don't
        remove decls that have DECL_RTL_SET_P.
        * passes.c (rest_of_decl_compilation): Invoke
        cgraph_varpool_finalize_decl for all but functions.
cp/
        * decl.c (wrapup_globals_for_namespace): Call
        emit_debug_global_declarations.
        * decl2.c (cp_finish_file): Likewise.

From-SVN: r104065

gcc/ChangeLog

+2005-09-08  Richard Henderson  <rth@redhat.com>
+
+	PR debug/23190
+	* toplev.c (wrapup_global_declaration_1): Split out ...
+	(wrapup_global_declaration_2): ... from ...
+	(wrapup_global_declarations): ... here.  Return bool.
+	(check_global_declaration_1): Split out ...
+	(check_global_declarations): from here.
+	(emit_debug_global_declarations): New.
+	* toplev.h (wrapup_global_declaration_1, wrapup_global_declaration_2,
+	check_global_declaration_1, emit_debug_global_declarations): Declare.
+	* c-decl.c (c_write_global_declarations_1): Don't create a vector
+	of decls.  Call wrapup_global_declaration_1,
+	wrapup_global_declaration_2, check_global_declaration_1 directly.
+	(c_write_global_declarations_2): New.
+	(ext_block): New.
+	(c_write_global_declarations): Call c_write_global_declarations_2.
+	* langhooks.c (write_global_declarations): Call
+	emit_debug_global_declarations.
+
+	* cgraphunit.c (cgraph_varpool_remove_unreferenced_decls): Don't
+	remove decls that have DECL_RTL_SET_P.
+	* passes.c (rest_of_decl_compilation): Invoke
+	cgraph_varpool_finalize_decl for all but functions.
+
 2005-09-08  Eric Botcazou  <ebotcazou@libertysurf.fr>
 
 	* tree-vrp.c (extract_range_from_unary_expr): Do not set the range for

gcc/c-decl.c

@@ -7540,20 +7540,18 @@ build_cdtor (int method_type, tree cdtors)
   cgraph_build_static_cdtor (method_type, body, DEFAULT_INIT_PRIORITY);
 }
 
-/* Perform final processing on one file scope's declarations (or the
-   external scope's declarations), GLOBALS.  */
+/* A subroutine of c_write_global_declarations.  Perform final processing
+   on one file scope's declarations (or the external scope's declarations),
+   GLOBALS.  */
+
 static void
 c_write_global_declarations_1 (tree globals)
 {
-  size_t len = list_length (globals);
-  tree *vec = XNEWVEC (tree, len);
-  size_t i;
   tree decl;
 
   /* Process the decls in the order they were written.  */
-  for (i = 0, decl = globals; i < len; i++, decl = TREE_CHAIN (decl))
+  for (decl = globals; decl; decl = TREE_CHAIN (decl))
     {
-      vec[i] = decl;
       /* Check for used but undefined static functions using the C
 	 standard's definition of "used", and set TREE_NO_WARNING so
 	 that check_global_declarations doesn't repeat the check.  */
@@ -7566,18 +7564,32 @@ c_write_global_declarations_1 (tree globals)
 	  pedwarn ("%q+F used but never defined", decl);
 	  TREE_NO_WARNING (decl) = 1;
 	}
+
+      wrapup_global_declaration_1 (decl);
+      wrapup_global_declaration_2 (decl);
+      check_global_declaration_1 (decl);
     }
+}
 
-  wrapup_global_declarations (vec, len);
-  check_global_declarations (vec, len);
+/* A subroutine of c_write_global_declarations Emit debug information for each
+   of the declarations in GLOBALS.  */
+
+static void
+c_write_global_declarations_2 (tree globals)
+{
+  tree decl;
 
-  free (vec);
+  for (decl = globals; decl ; decl = TREE_CHAIN (decl))
+    debug_hooks->global_decl (decl);
 }
 
+/* Preserve the external declarations scope across a garbage collect.  */
+static GTY(()) tree ext_block;
+
 void
 c_write_global_declarations (void)
 {
-  tree ext_block, t;
+  tree t;
 
   /* We don't want to do this if generating a PCH.  */
   if (pch_file)
@@ -7593,10 +7605,6 @@ c_write_global_declarations (void)
   external_scope = 0;
   gcc_assert (!current_scope);
 
-  /* Process all file scopes in this compilation, and the external_scope,
-     through wrapup_global_declarations and check_global_declarations.  */
-  for (t = all_translation_units; t; t = TREE_CHAIN (t))
-    c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
   if (ext_block)
     {
       tree tmp = BLOCK_VARS (ext_block);
@@ -7608,6 +7616,11 @@ c_write_global_declarations (void)
           dump_end (TDI_tu, stream);
         }
     }
+
+  /* Process all file scopes in this compilation, and the external_scope,
+     through wrapup_global_declarations and check_global_declarations.  */
+  for (t = all_translation_units; t; t = TREE_CHAIN (t))
+    c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
   c_write_global_declarations_1 (BLOCK_VARS (ext_block));
 
   /* Generate functions to call static constructors and destructors
@@ -7619,6 +7632,19 @@ c_write_global_declarations (void)
   /* We're done parsing; proceed to optimize and emit assembly.
      FIXME: shouldn't be the front end's responsibility to call this.  */
   cgraph_optimize ();
+
+  /* After cgraph has had a chance to emit everything that's going to
+     be emitted, output debug information for globals.  */
+  if (errorcount == 0 && sorrycount == 0)
+    {
+      timevar_push (TV_SYMOUT);
+      for (t = all_translation_units; t; t = TREE_CHAIN (t))
+	c_write_global_declarations_2 (BLOCK_VARS (DECL_INITIAL (t)));
+      c_write_global_declarations_2 (BLOCK_VARS (ext_block));
+      timevar_pop (TV_SYMOUT);
+    }
+
+  ext_block = NULL;
 }
 
 #include "gt-c-decl.h"

gcc/cgraphunit.c

@@ -311,7 +311,13 @@ cgraph_varpool_remove_unreferenced_decls (void)
 	  && ((DECL_ASSEMBLER_NAME_SET_P (decl)
 	       && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
 	      || node->force_output
-	      || decide_is_variable_needed (node, decl)))
+	      || decide_is_variable_needed (node, decl)
+	      /* ??? Cgraph does not yet rule the world with an iron hand, 
+		 and does not control the emission of debug information.
+		 After a variable has its DECL_RTL set, we must assume that
+		 it may be referenced by the debug information, and we can
+		 no longer elide it.  */
+	      || DECL_RTL_SET_P (decl)))
 	cgraph_varpool_mark_needed_node (node);
 
       node = next;

gcc/cp/ChangeLog

+2005-09-08  Richard Henderson  <rth@redhat.com>
+
+	PR debug/23190
+	* decl.c (wrapup_globals_for_namespace): Call
+	emit_debug_global_declarations.
+	* decl2.c (cp_finish_file): Likewise.
+
 2005-09-08  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/23691

gcc/cp/decl.c

@@ -789,6 +789,7 @@ wrapup_globals_for_namespace (tree namespace, void* data)
   if (last_time)
     {
       check_global_declarations (vec, len);
+      emit_debug_global_declarations (vec, len);
       return 0;
     }
 

gcc/cp/decl2.c

@@ -3106,8 +3106,12 @@ cp_finish_file (void)
      etc., and emit debugging information.  */
   walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider);
   if (VEC_length (tree, pending_statics) != 0)
+    {
       check_global_declarations (VEC_address (tree, pending_statics),
 			         VEC_length (tree, pending_statics));
+      emit_debug_global_declarations (VEC_address (tree, pending_statics),
+				      VEC_length (tree, pending_statics));
+    }
 
   /* Generate hidden aliases for Java.  */
   build_java_method_aliases ();

gcc/langhooks.c

@@ -478,8 +478,8 @@ write_global_declarations (void)
     vec[len - i - 1] = decl;
 
   wrapup_global_declarations (vec, len);
-
   check_global_declarations (vec, len);
+  emit_debug_global_declarations (vec, len);
 
   /* Clean up.  */
   free (vec);

gcc/passes.c

@@ -158,8 +158,7 @@ rest_of_decl_compilation (tree decl,
 	   || DECL_INITIAL (decl))
 	  && !DECL_EXTERNAL (decl))
 	{
-	  if (flag_unit_at_a_time && !cgraph_global_info_ready
-	      && TREE_CODE (decl) != FUNCTION_DECL)
+	  if (TREE_CODE (decl) != FUNCTION_DECL)
 	    cgraph_varpool_finalize_decl (decl);
 	  else
 	    assemble_variable (decl, top_level, at_end, 0);

gcc/testsuite/gcc.dg/debug/20050907-1.c

+/* PR 23190 */
+/* Well, collateral damage from a proposed patch fixing 23190.  We'd emit
+   debug info for multilib_exclusions_raw without emitting the variable
+   itself, leading to link errors.  This reduced form is filed as PR 23777,
+   for not eliminating things soon enough.  */
+/* { dg-do link } */
+
+static const char *const multilib_exclusions_raw[] = { 0 };
+
+void __attribute__((noinline)) f(char *const *p)
+{
+  __asm__ ("" : : "g"(p) : "memory");
+}
+
+void g (char **o)
+{
+  const char *const *q = multilib_exclusions_raw;
+
+  f (o);
+  while (*q++)
+    f (o);
+}
+
+int main() { return 0; }

gcc/testsuite/gcc.dg/debug/dwarf2/var1.c

+/* PR 23190 */
+/* { dg-do compile }
+/* { dg-options "-gdwarf-2 -dA" } */
+/* { dg-final { scan-assembler "xyzzy\[^\\n\\r\]+DW_AT_name" } } */
+
+void f(void)
+{
+   static int xyzzy;
+   xyzzy += 3;
+}

gcc/testsuite/gcc.dg/debug/dwarf2/var2.c

+/* PR 23190 */
+/* { dg-do compile }
+/* { dg-options "-O2 -gdwarf-2 -dA" } */
+/* { dg-final { scan-assembler "DW_OP_addr\[\\n\\r\]+\[^\\n\\r\]+foo" } } */
+/* { dg-final { scan-assembler "DW_OP_addr\[\\n\\r\]+\[^\\n\\r\]+bar" } } */
+
+static int foo;
+int bar;
+int main(void)
+{
+   foo += 3;
+   bar *= 5;
+   return 0;
+}

gcc/toplev.c

@@ -685,45 +685,31 @@ output_file_directive (FILE *asm_file, const char *input_name)
 #endif
 }
 
-/* Do any final processing required for the declarations in VEC, of
-   which there are LEN.  We write out inline functions and variables
-   that have been deferred until this point, but which are required.
-   Returns nonzero if anything was put out.  */
+/* A subroutine of wrapup_global_declarations.  We've come to the end of
+   the compilation unit.  All deferred variables should be undeferred,
+   and all incomplete decls should be finalized.  */
 
-int
-wrapup_global_declarations (tree *vec, int len)
+void
+wrapup_global_declaration_1 (tree decl)
 {
-  tree decl;
-  int i;
-  int reconsider;
-  int output_something = 0;
-
-  for (i = 0; i < len; i++)
-    {
-      decl = vec[i];
-
-      /* We're not deferring this any longer.  Assignment is
-	 conditional to avoid needlessly dirtying PCH pages.  */
+  /* We're not deferring this any longer.  Assignment is conditional to
+     avoid needlessly dirtying PCH pages.  */
   if (CODE_CONTAINS_STRUCT (TREE_CODE (decl), TS_DECL_WITH_VIS)
       && DECL_DEFER_OUTPUT (decl) != 0)
     DECL_DEFER_OUTPUT (decl) = 0;
 
   if (TREE_CODE (decl) == VAR_DECL && DECL_SIZE (decl) == 0)
     lang_hooks.finish_incomplete_decl (decl);
-    }
+}
 
-  /* Now emit any global variables or functions that we have been
-     putting off.  We need to loop in case one of the things emitted
-     here references another one which comes earlier in the list.  */
-  do
-    {
-      reconsider = 0;
-      for (i = 0; i < len; i++)
-	{
-	  decl = vec[i];
+/* A subroutine of wrapup_global_declarations.  Decide whether or not DECL
+   needs to be output.  Return true if it is output.  */
 
+bool
+wrapup_global_declaration_2 (tree decl)
+{
   if (TREE_ASM_WRITTEN (decl) || DECL_EXTERNAL (decl))
-	    continue;
+    return false;
 
   /* Don't write out static consts, unless we still need them.
 
@@ -753,13 +739,13 @@ wrapup_global_declarations (tree *vec, int len)
   if (TREE_CODE (decl) == VAR_DECL && TREE_STATIC (decl))
     {
       struct cgraph_varpool_node *node;
-	      bool needed = 1;
+      bool needed = true;
       node = cgraph_varpool_node (decl);
 
       if (node->finalized)
-		needed = 0;
+	needed = false;
       else if (node->alias)
-		needed = 0;
+	needed = false;
       else if (!cgraph_global_info_ready
 	       && (TREE_USED (decl)
 		   || TREE_USED (DECL_ASSEMBLER_NAME (decl))))
@@ -767,45 +753,60 @@ wrapup_global_declarations (tree *vec, int len)
       else if (node->needed)
 	/* needed */;
       else if (DECL_COMDAT (decl))
-		needed = 0;
+	needed = false;
       else if (TREE_READONLY (decl) && !TREE_PUBLIC (decl)
 	       && (optimize || !flag_keep_static_consts
 		   || DECL_ARTIFICIAL (decl)))
-		needed = 0;
+	needed = false;
 
       if (needed)
 	{
-		  reconsider = 1;
 	  rest_of_decl_compilation (decl, 1, 1);
+	  return true;
 	}
     }
-	}
 
+  return false;
+}
+
+/* Do any final processing required for the declarations in VEC, of
+   which there are LEN.  We write out inline functions and variables
+   that have been deferred until this point, but which are required.
+   Returns nonzero if anything was put out.  */
+
+bool
+wrapup_global_declarations (tree *vec, int len)
+{
+  bool reconsider, output_something = false;
+  int i;
+
+  for (i = 0; i < len; i++)
+    wrapup_global_declaration_1 (vec[i]);
+
+  /* Now emit any global variables or functions that we have been
+     putting off.  We need to loop in case one of the things emitted
+     here references another one which comes earlier in the list.  */
+  do
+    {
+      reconsider = false;
+      for (i = 0; i < len; i++)
+	reconsider |= wrapup_global_declaration_2 (vec[i]);
       if (reconsider)
-	output_something = 1;
+	output_something = true;
     }
   while (reconsider);
 
   return output_something;
 }
 
-/* Issue appropriate warnings for the global declarations in VEC (of
-   which there are LEN).  Output debugging information for them.  */
+/* A subroutine of check_global_declarations.  Issue appropriate warnings
+   for the global declaration DECL.  */
 
 void
-check_global_declarations (tree *vec, int len)
+check_global_declaration_1 (tree decl)
 {
-  tree decl;
-  int i;
-
-  for (i = 0; i < len; i++)
-    {
-      decl = vec[i];
-
-      /* Warn about any function
-	 declared static but not defined.
-	 We don't warn about variables,
-	 because many programs have static variables
+  /* Warn about any function declared static but not defined.  We don't
+     warn about variables, because many programs have static variables
      that exist only to get some text into the object file.  */
   if (TREE_CODE (decl) == FUNCTION_DECL
       && DECL_INITIAL (decl) == 0
@@ -819,8 +820,7 @@ check_global_declarations (tree *vec, int len)
       if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
 	pedwarn ("%q+F used but never defined", decl);
       else
-	    warning (0, "%q+F declared %<static%> but never defined",
-		     decl);
+	warning (0, "%q+F declared %<static%> but never defined", decl);
       /* This symbol is effectively an "extern" declaration now.  */
       TREE_PUBLIC (decl) = 1;
       assemble_external (decl);
@@ -846,16 +846,35 @@ check_global_declarations (tree *vec, int len)
       /* Otherwise, ask the language.  */
       && lang_hooks.decls.warn_unused_global (decl))
     warning (0, "%q+D defined but not used", decl);
+}
+
+/* Issue appropriate warnings for the global declarations in VEC (of
+   which there are LEN).  */
+
+void
+check_global_declarations (tree *vec, int len)
+{
+  int i;
+
+  for (i = 0; i < len; i++)
+    check_global_declaration_1 (vec[i]);
+}
+
+/* Emit debugging information for all global declarations in VEC.  */
+
+void
+emit_debug_global_declarations (tree *vec, int len)
+{
+  int i;
+
+  /* Avoid confusing the debug information machinery when there are errors.  */
+  if (errorcount != 0 || sorrycount != 0)
+    return;
 
-      /* Avoid confusing the debug information machinery when there are
-	 errors.  */
-      if (errorcount == 0 && sorrycount == 0)
-	{
   timevar_push (TV_SYMOUT);
-	  (*debug_hooks->global_decl) (decl);
+  for (i = 0; i < len; i++)
+    debug_hooks->global_decl (vec[i]);
   timevar_pop (TV_SYMOUT);
-	}
-    }
 }
 
 /* Warn about a use of an identifier which was marked deprecated.  */

gcc/toplev.h

@@ -92,8 +92,12 @@ extern void fnotice			(FILE *, const char *, ...)
      ATTRIBUTE_PRINTF_2;
 #endif
 
-extern int wrapup_global_declarations (tree *, int);
+extern void wrapup_global_declaration_1 (tree);
+extern bool wrapup_global_declaration_2 (tree);
+extern bool wrapup_global_declarations (tree *, int);
+extern void check_global_declaration_1 (tree);
 extern void check_global_declarations (tree *, int);
+extern void emit_debug_global_declarations (tree *, int);
 extern void write_global_declarations (void);
 
 /* A unique local time stamp, might be zero if none is available.  */