PR c++/84454 - ICE with pack expansion in signature.

	* error.c (find_typenames_r): Also stop on EXPR_PACK_EXPANSION.

From-SVN: r257875

gcc/cp/ChangeLog

+2018-02-21  Jason Merrill  <jason@redhat.com>
+
+	PR c++/84454 - ICE with pack expansion in signature.
+	* error.c (find_typenames_r): Also stop on EXPR_PACK_EXPANSION.
+
 2018-02-20  Siddhesh Poyarekar  <siddhesh@sourceware.org>
 
 	* cp-objcp-common.c (cxx_block_may_fallthru): Add case for

gcc/cp/error.c

@@ -1472,7 +1472,7 @@ find_typenames_r (tree *tp, int *walk_subtrees, void *data)
     /* Add the typename without any cv-qualifiers.  */
     mv = TYPE_MAIN_VARIANT (*tp);
 
-  if (TREE_CODE (*tp) == TYPE_PACK_EXPANSION)
+  if (PACK_EXPANSION_P (*tp))
     {
       /* Don't mess with parameter packs since we don't remember
 	 the pack expansion context for a particular typename.  */

gcc/testsuite/g++.dg/cpp0x/variadic172.C

+// PR c++/84454
+// { dg-do compile { target c++11 } }
+
+template<class F, class... A>
+void
+g(F&&, A&&...)
+{}
+
+template<class... A>
+auto
+h(A&&... a) -> decltype(g(0, g<decltype(a)>(a)...))
+{
+  g(a...);			// { dg-error "no match" }
+}
+
+int
+main()
+{
+  h();
+}