The code I added for dealing with fixed parameter packs wasn't dealing
properly with zero-length packs: if there were any elements we would see
the pack expansion argument and punt, but we need to do that in the
zero-length case as well.
Tested x86_64-pc-linux-gnu, applying to trunk and 4.9.
commit 8fa00de341538399cd675d50a6b1cb86bda39159
Author: Jason Merrill <ja...@redhat.com>
Date: Mon Jan 12 22:00:26 2015 -0500
PR c++/64514
* pt.c (coerce_template_parameter_pack): Return NULL for a
zero-length fixed parameter pack with a pack expansion arg.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 3ac93db..55871e5 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -6825,6 +6825,9 @@ coerce_template_parameter_pack (tree parms,
if (invalid_nontype_parm_type_p (t, complain))
return error_mark_node;
}
+ /* We don't know how many args we have yet, just
+ use the unconverted ones for now. */
+ return NULL_TREE;
}
packed_args = make_tree_vec (TREE_VEC_LENGTH (packed_parms));
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic165.C b/gcc/testsuite/g++.dg/cpp0x/variadic165.C
new file mode 100644
index 0000000..862931f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic165.C
@@ -0,0 +1,17 @@
+// PR c++/64514
+// { dg-do compile { target c++11 } }
+
+template<typename... T>
+struct Functor
+{
+ template <T...>
+ struct Inner
+ {};
+};
+
+template struct Functor<>::Inner<>;
+
+int main()
+{
+
+}
