From 8b1d0e0f8d8667c8f71aa00080108115d6891354 Mon Sep 17 00:00:00 2001
From: jason <jason@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed, 25 May 2011 15:26:14 +0000
Subject: [PATCH] 	PR c++/48292
 	* pt.c (tsubst_decl) [PARM_DECL]: Handle partial instantiation of
 	function parameter pack.
 	(tsubst_pack_expansion): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@174207 138bc75d-0d04-0410-961f-82ee72b054a4

index b16d229..d379a8c 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -8690,7 +8690,12 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
 		 have the wrong value for a recursive call.  Just make a
 		 dummy decl, since it's only used for its type.  */
 	      arg_pack = tsubst_decl (parm_pack, args, complain);
-	      arg_pack = make_fnparm_pack (arg_pack);
+	      if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
+		/* Partial instantiation of the parm_pack, we can't build
+		   up an argument pack yet.  */
+		arg_pack = NULL_TREE;
+	      else
+		arg_pack = make_fnparm_pack (arg_pack);
 	    }
 	}
       else
@@ -9780,14 +9785,14 @@ tsubst_decl (tree t, tree args, tsubst_flags_t complain)
             if (DECL_TEMPLATE_PARM_P (t))
               SET_DECL_TEMPLATE_PARM_P (r);
 
-	    /* An argument of a function parameter pack is not a parameter
-	       pack.  */
-	    FUNCTION_PARAMETER_PACK_P (r) = false;
-
             if (expanded_types)
               /* We're on the Ith parameter of the function parameter
                  pack.  */
               {
+		/* An argument of a function parameter pack is not a parameter
+		   pack.  */
+		FUNCTION_PARAMETER_PACK_P (r) = false;
+
                 /* Get the Ith type.  */
                 type = TREE_VEC_ELT (expanded_types, i);
 
new file mode 100644
index 0000000..0ec69af
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic109.C
@@ -0,0 +1,17 @@
+// PR c++/48292
+// { dg-options -std=c++0x }
+
+template <typename... Args> int g(Args...);
+
+template <int N = 0>
+struct A
+{
+    template <typename... Args>
+    static auto f(Args... args) -> decltype(g(args...));
+};
+
+int main()
+{
+    A<>::f();
+    return 0;
+}
-- 
1.7.0.4