From 99d4f8f70432e889eaa87f2a00a69f8b3481ff63 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Mon, 16 Apr 2012 22:29:27 -0400
Subject: [PATCH] re PR c++/50303 ([C++0x] Segfault with variadic template
 template parameters)

	PR c++/50303
	* pt.c (tsubst_pack_expansion): Use tsubst_expr for template
	template parameters.

From-SVN: r186519
---
 gcc/cp/ChangeLog                         |  6 ++++++
 gcc/cp/pt.c                              |  2 +-
 gcc/testsuite/ChangeLog                  |  5 +++++
 gcc/testsuite/g++.dg/cpp0x/variadic128.C | 16 ++++++++++++++++
 4 files changed, 28 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/variadic128.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 71cf71c0606..3f2b9991161 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2012-04-16  Jason Merrill  <jason@redhat.com>
+
+	PR c++/50303
+	* pt.c (tsubst_pack_expansion): Use tsubst_expr for template
+	template parameters.
+
 2012-04-16  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/49152
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 95d0aba0534..742378179a2 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -9518,7 +9518,7 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
         }
 
       /* Substitute into the PATTERN with the altered arguments.  */
-      if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
+      if (!TYPE_P (pattern))
         TREE_VEC_ELT (result, i) = 
           tsubst_expr (pattern, args, complain, in_decl,
                        /*integral_constant_expression_p=*/false);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 79a724ebb9c..42e33c7452c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2012-04-16  Jason Merrill  <jason@redhat.com>
+
+	PR c++/50303
+	* g++.dg/cpp0x/variadic128.C: New.
+
 2012-04-16  Tobias Burnus  <burnus@net-b.de>
 
 	PR fortran/52864
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic128.C b/gcc/testsuite/g++.dg/cpp0x/variadic128.C
new file mode 100644
index 00000000000..8c2d3b23359
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic128.C
@@ -0,0 +1,16 @@
+// PR c++/50303
+// { dg-do compile { target c++11 } }
+
+template<typename Interface>
+struct A1 {
+};
+
+template<template<class I> class... Actions>
+void g2() {
+  g2<Actions...>();
+}
+
+int main()
+{
+  g2<A1>();
+}
-- 
2.30.2