re PR c++/55564 (internal error using decltype of a template type parameter for…

re PR c++/55564 (internal error using decltype of a template type parameter for late-specified function result type)

	PR c++/55564
	* pt.c (unify) [ARRAY_TYPE]: Unify the element type before the bounds.

From-SVN: r194248

gcc/cp/ChangeLog

+2012-12-06  Jason Merrill  <jason@redhat.com>
+
+	PR c++/55564
+	* pt.c (unify) [ARRAY_TYPE]: Unify the element type before the bounds.
+
 2012-12-03  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/54170

gcc/cp/pt.c

@@ -16593,6 +16593,8 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
       if ((TYPE_DOMAIN (parm) == NULL_TREE)
 	  != (TYPE_DOMAIN (arg) == NULL_TREE))
 	return unify_type_mismatch (explain_p, parm, arg);
+      RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
+			       strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
       if (TYPE_DOMAIN (parm) != NULL_TREE)
 	{
 	  tree parm_max;
@@ -16651,8 +16653,7 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
 	  RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
 				   UNIFY_ALLOW_INTEGER, explain_p);
 	}
-      return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
-		    strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
+      return unify_success (explain_p);
 
     case REAL_TYPE:
     case COMPLEX_TYPE:

gcc/testsuite/g++.dg/cpp0x/decltype47.C

+// PR c++/55564
+// { dg-options -std=c++11 }
+
+template <typename T, decltype(sizeof(T)) N>
+auto array_size(T(&)[N]) -> decltype(N) { return N; }
+
+int main() {
+  int simple[4] = {};
+  int result =  array_size(simple);
+
+  return result;
+}