re PR debug/43942 (-fcompare-debug faulure with external declaration in function.)

	PR debug/43942
	* tree.c (auto_var_in_fn_p): Return false for DECL_EXTERNAL vars.

	* c-c++-common/pr43942.c: New test.

From-SVN: r158931

gcc/ChangeLog

+2010-04-30  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/43942
+	* tree.c (auto_var_in_fn_p): Return false for DECL_EXTERNAL vars.
+
 2010-04-30  Hariharan Sandanagobalane  <hariharan@picochip.com>
 
 	* config/picochip/picochip.c (picochip_legitimize_address): Define.

gcc/testsuite/ChangeLog

+2010-04-30  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/43942
+	* c-c++-common/pr43942.c: New test.
+
 2009-04-30  Steven Bosscher  <steven@gcc.gnu.org>
 
 	* gcc.dg/lto/20091216-1_0.c: Adjust test case to avoid

gcc/testsuite/c-c++-common/pr43942.c

+/* PR debug/43942 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fcompare-debug" } */
+
+extern int f1 (int);
+
+int
+f2 (int x)
+{
+  extern int v;
+  return f1 (x);
+}
+
+void
+f3 (void)
+{
+  f2 (0);
+}
+
+static inline int
+f4 (int x)
+{
+  extern int w;
+  if (w)
+    return f1 (x);
+  return 0;
+}
+
+void
+f5 (void)
+{
+  f4 (0);
+}

gcc/tree.c

@@ -7936,7 +7936,8 @@ bool
 auto_var_in_fn_p (const_tree var, const_tree fn)
 {
   return (DECL_P (var) && DECL_CONTEXT (var) == fn
-	  && (((TREE_CODE (var) == VAR_DECL || TREE_CODE (var) == PARM_DECL)
+	  && ((((TREE_CODE (var) == VAR_DECL && ! DECL_EXTERNAL (var))
+		|| TREE_CODE (var) == PARM_DECL)
 	       && ! TREE_STATIC (var))
 	      || TREE_CODE (var) == LABEL_DECL
 	      || TREE_CODE (var) == RESULT_DECL));