From ebcb4bc3047888b1c9a655255c56257ff32dbc0b Mon Sep 17 00:00:00 2001
From: Dodji Seketeli <dodji@redhat.com>
Date: Wed, 16 Feb 2011 20:45:15 +0000
Subject: [PATCH] re PR c++/47326 ([C++0x] ICE in tsubst_copy (triggered by
 dependency of return type on parameter pack size))

PR c++/47326

gcc/cp/

	PR c++/47326
	* pt.c (tsubst_copy)<case SIZEOF_EXPR>: Ensure that even pack
	expansion arguments are not evaluated.

gcc/testsuite/

	PR c++/47326
	* g++.dg/cpp0x/variadic106.C: New test.

From-SVN: r170222
---
 gcc/cp/ChangeLog                         |  6 ++++++
 gcc/cp/pt.c                              | 13 ++++++++++---
 gcc/testsuite/ChangeLog                  |  5 +++++
 gcc/testsuite/g++.dg/cpp0x/variadic106.C | 22 ++++++++++++++++++++++
 4 files changed, 43 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/variadic106.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index d2972eb..dca9612 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2011-02-16  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/47326
+	* pt.c (tsubst_copy)<case SIZEOF_EXPR>: Ensure that even pack
+    	expansion arguments are not evaluated.
+
 2011-02-16  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/47704
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index fe3e954..aa956c8 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -11382,11 +11382,18 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
     case SIZEOF_EXPR:
       if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
         {
-          /* We only want to compute the number of arguments.  */
-          tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
-                                                complain, in_decl);
+
+          tree expanded;
 	  int len = 0;
 
+	  ++cp_unevaluated_operand;
+	  ++c_inhibit_evaluation_warnings;
+	  /* We only want to compute the number of arguments.  */
+	  expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
+					    complain, in_decl);
+	  --cp_unevaluated_operand;
+	  --c_inhibit_evaluation_warnings;
+
 	  if (TREE_CODE (expanded) == TREE_VEC)
 	    len = TREE_VEC_LENGTH (expanded);
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index a25d496..e11bdf3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-02-16  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/47326
+	* g++.dg/cpp0x/variadic106.C: New test.
+
 2011-02-16  Jakub Jelinek  <jakub@redhat.com>
 
 	PR libfortran/47757
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic106.C b/gcc/testsuite/g++.dg/cpp0x/variadic106.C
new file mode 100644
index 0000000..80ec084
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic106.C
@@ -0,0 +1,22 @@
+// Origin: PR c++/47326
+// { dg-options  "-std=c++0x" }
+// { dg-do compile }
+
+template <int _N>
+struct A
+{
+  typedef int value_type;
+};
+
+template <typename... _ARGS>
+auto
+f (_ARGS... args) -> typename A<sizeof...(args)>::value_type
+{
+  return 12;
+}
+
+int
+main()
+{
+  f(1,2);
+}
-- 
2.7.4