re PR c++/56377 (<missing> template args in substitution-failure diagnostics)

	PR c++/56377
	* pt.c (fn_type_unification): Use explicit args in template
	instantiation context.

From-SVN: r196230

gcc/cp/ChangeLog

 2013-02-22  Jason Merrill  <jason@redhat.com>
 
+	PR c++/56377
+	* pt.c (fn_type_unification): Use explicit args in template
+	instantiation context.
+
 	PR c++/56359
 	* call.c (can_convert_arg): Discard access checks.
 

gcc/cp/pt.c

@@ -15008,8 +15008,10 @@ fn_type_unification (tree fn,
 
       processing_template_decl += incomplete;
       input_location = DECL_SOURCE_LOCATION (fn);
+      TREE_VALUE (tinst) = explicit_targs;
       fntype = tsubst (TREE_TYPE (fn), explicit_targs,
 		       complain | tf_partial, NULL_TREE);
+      TREE_VALUE (tinst) = targs;
       input_location = loc;
       processing_template_decl -= incomplete;