re PR c++/64603 (bogus error "no matching function for call to ..." with templates)

	PR c++/64603
	* constexpr.c (cxx_eval_constant_expression): Only shortcut
	constant CONSTRUCTORs.

From-SVN: r219973

gcc/cp/ChangeLog

 2015-01-21  Jason Merrill  <jason@redhat.com>
 
+	PR c++/64603
+	* constexpr.c (cxx_eval_constant_expression): Only shortcut
+	constant CONSTRUCTORs.
+
 	PR c++/64647
 	* constexpr.c (ensure_literal_type_for_constexpr_object): Don't
 	give a hard error in a template instantiation.

gcc/cp/constexpr.c

@@ -2943,9 +2943,6 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t,
 	*overflow_p = true;
       return t;
     }
-  if (TREE_CODE (t) != NOP_EXPR
-      && reduced_constant_expression_p (t))
-    return fold (t);
 
   switch (TREE_CODE (t))
     {
@@ -3315,6 +3312,10 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t,
       break;
 
     case CONSTRUCTOR:
+      if (TREE_CONSTANT (t))
+	/* Don't re-process a constant CONSTRUCTOR, but do fold it to
+	   VECTOR_CST if applicable.  */
+	return fold (t);
       r = cxx_eval_bare_aggregate (ctx, t, lval,
 				   non_constant_p, overflow_p);
       break;

gcc/testsuite/g++.dg/cpp0x/constexpr-sizeof1.C

+// PR c++/64603
+// { dg-do compile { target c++11 } }
+
+template <int i> constexpr int find_longest_name()
+{
+  return sizeof("Main") - 1;
+}
+
+template <int i, int l = find_longest_name<i>()> void create_all_loggers()
+{}
+
+int main()
+{
+  create_all_loggers<1>();
+}