Fix constraint satisfaction in uninstantiated template.

	* constraint.cc (constraints_satisfied_p): Keep as many levels of
	args as our template has levels of parms.

From-SVN: r237655

gcc/cp/ChangeLog

 2016-06-21  Jason Merrill  <jason@redhat.com>
 
+	* constraint.cc (constraints_satisfied_p): Keep as many levels of
+	args as our template has levels of parms.
+
 	* pt.c (template_parm_outer_level, uses_outer_template_parms): New.
 	(type_dependent_expression_p): Use uses_outer_template_parms.
 

gcc/cp/constraint.cc

@@ -2122,8 +2122,10 @@ constraints_satisfied_p (tree decl)
   tree args = NULL_TREE;
   if (tree ti = DECL_TEMPLATE_INFO (decl))
     {
-      ci = get_constraints (TI_TEMPLATE (ti));
-      args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (ti));
+      tree tmpl = TI_TEMPLATE (ti);
+      ci = get_constraints (tmpl);
+      int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
+      args = get_innermost_template_args (TI_ARGS (ti), depth);
     }
   else
     {

gcc/testsuite/g++.dg/concepts/memtmpl1.C

+// { dg-options "-std=c++1z -fconcepts" }
+
+template <class T>
+struct A {
+  template <class U>
+  requires sizeof(T) == 1
+    static void f(U);
+  template <class U>
+  requires sizeof(T) == 2
+    static void f(U);
+  void g()
+  {
+    f(42);
+  }
+};