Core 1609

	Core 1609
	* decl2.c (check_default_args): Check for pack expansion.

From-SVN: r198152

gcc/cp/ChangeLog

 2013-04-22  Jason Merrill  <jason@redhat.com>
 
+	Core 1609
+	* decl2.c (check_default_args): Check for pack expansion.
+
 	* mangle.c (write_type): Mangle decltype(auto).
 
 2013-04-19  Jason Merrill  <jason@redhat.com>

gcc/cp/decl2.c

@@ -4463,7 +4463,7 @@ check_default_args (tree x)
     {
       if (TREE_PURPOSE (arg))
 	saw_def = true;
-      else if (saw_def)
+      else if (saw_def && !PACK_EXPANSION_P (TREE_VALUE (arg)))
 	{
 	  error ("default argument missing for parameter %P of %q+#D", i, x);
 	  TREE_PURPOSE (arg) = error_mark_node;

gcc/testsuite/g++.dg/cpp0x/variadic142.C

+// Core 1609
+// { dg-require-effective-target c++11 }
+
+template<typename... T>
+void f2(int a = 0, T... b, int c = 1);
+
+int main(){
+  f2<>(); // parameter a has the value 0 and parameter c has the value 1
+}