re PR c++/54198 ("error: invalid use of incomplete type" when building Chromium)

	PR c++/54198
	* decl.c (check_default_argument): Set cp_unevaluated_operand
	around call to perform_implicit_conversion_flags.

From-SVN: r190949

gcc/cp/ChangeLog

 2012-09-04  Jason Merrill  <jason@redhat.com>
 
+	PR c++/54198
+	* decl.c (check_default_argument): Set cp_unevaluated_operand
+	around call to perform_implicit_conversion_flags.
+
 	PR c++/54437
 	PR c++/51213
 	* pt.c (fn_type_unification): Call coerce_template_parms before

gcc/cp/decl.c

@@ -10575,8 +10575,10 @@ check_default_argument (tree decl, tree arg)
 
      A default argument expression is implicitly converted to the
      parameter type.  */
+  ++cp_unevaluated_operand;
   perform_implicit_conversion_flags (decl_type, arg, tf_warning_or_error,
 				     LOOKUP_NORMAL);
+  --cp_unevaluated_operand;
 
   if (warn_zero_as_null_pointer_constant
       && c_inhibit_evaluation_warnings == 0

gcc/testsuite/ChangeLog

 2012-09-04  Jason Merrill  <jason@redhat.com>
 
+	PR c++/54198
+	* g++.dg/template/defarg15.C: New.
+
 	PR c++/54437
 	* g++.dg/template/access24.C: New.
 

gcc/testsuite/g++.dg/template/defarg15.C

+// PR c++/54198
+
+template <typename T> void
+refIfNotNull (T* p1)
+{
+    p1->ref;
+}
+template <typename T> struct A
+{
+    A (T* p1)
+    {
+        refIfNotNull (p1);
+    }
+};
+class B;
+class C
+{
+    void getParent (A <B> = 0);
+};