re PR middle-end/41611 (guard variable is emitted even when the guarded symbol isn't)

	PR c++/41611
	* decl2.c (get_guard): Don't use the same comdat group as the decl.

From-SVN: r154965

gcc/cp/ChangeLog

 2009-12-03  Jason Merrill  <jason@redhat.com>
 
+	PR c++/41611
+	* decl2.c (get_guard): Don't use the same comdat group as the decl.
+
 	PR c++/42266
 	* cvt.c (convert_from_reference): Do nothing if TREE_TYPE is null.
 

gcc/cp/decl2.c

@@ -2555,7 +2555,8 @@ get_guard (tree decl)
       TREE_STATIC (guard) = TREE_STATIC (decl);
       DECL_COMMON (guard) = DECL_COMMON (decl);
       DECL_COMDAT (guard) = DECL_COMDAT (decl);
-      DECL_COMDAT_GROUP (guard) = DECL_COMDAT_GROUP (decl);
+      if (DECL_ONE_ONLY (decl))
+	make_decl_one_only (guard, cxx_comdat_group (guard));
       if (TREE_PUBLIC (decl))
 	DECL_WEAK (guard) = DECL_WEAK (decl);
       DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl);

gcc/testsuite/ChangeLog

 2009-12-03  Jason Merrill  <jason@redhat.com>
 
+	PR c++/41611
+	* g++.dg/abi/guard2.C: New.
+
 	PR c++/42266
 	* g++.dg/cpp0x/variadic97.C: New.
 

gcc/testsuite/g++.dg/abi/guard2.C

+// PR c++/41611
+// Test that the guard gets its own COMDAT group.
+// { dg-final { scan-assembler "_ZGVZN1A1fEvE1i,comdat" { target i?86-*-* x86_64-*-* } } }
+
+struct A {
+  static int f()
+  {
+    static int &i = *new int();
+    return i;
+  }
+};
+
+int main()
+{
+  return A::f();
+}