From 6dd054d54a30b1f13739855d6fb6a82f2725d0e6 Mon Sep 17 00:00:00 2001
From: jason <jason@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Thu, 14 Apr 2011 15:00:07 +0000
Subject: [PATCH] 	PR c++/48557 	* typeck.c (cp_build_binary_op): Don't
 decay void operands.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@172433 138bc75d-0d04-0410-961f-82ee72b054a4
---
 gcc/cp/ChangeLog                      |  3 +++
 gcc/cp/typeck.c                       |  8 ++++----
 gcc/testsuite/ChangeLog               |  2 ++
 gcc/testsuite/g++.dg/cpp0x/sfinae14.C | 27 +++++++++++++++++++++++++++
 4 files changed, 36 insertions(+), 4 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/sfinae14.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 0833125..1b60dd4 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2011-04-14  Jason Merrill  <jason@redhat.com>
 
+	PR c++/48557
+	* typeck.c (cp_build_binary_op): Don't decay void operands.
+
 	PR c++/48446
 	* decl.c (compute_array_index_type): Use get_temp_regvar instead
 	of variable_size.
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index ecd7d41..b0e2110 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -3646,16 +3646,16 @@ cp_build_binary_op (location_t location,
       || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
       || code == TRUTH_XOR_EXPR)
     {
-      if (!really_overloaded_fn (op0))
+      if (!really_overloaded_fn (op0) && !VOID_TYPE_P (TREE_TYPE (op0)))
 	op0 = decay_conversion (op0);
-      if (!really_overloaded_fn (op1))
+      if (!really_overloaded_fn (op1) && !VOID_TYPE_P (TREE_TYPE (op1)))
 	op1 = decay_conversion (op1);
     }
   else
     {
-      if (!really_overloaded_fn (op0))
+      if (!really_overloaded_fn (op0) && !VOID_TYPE_P (TREE_TYPE (op0)))
 	op0 = default_conversion (op0);
-      if (!really_overloaded_fn (op1))
+      if (!really_overloaded_fn (op1) && !VOID_TYPE_P (TREE_TYPE (op1)))
 	op1 = default_conversion (op1);
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 080d29b..8a5f5ae 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,7 @@
 2011-04-14  Jason Merrill  <jason@redhat.com>
 
+	* g++.dg/cpp0x/sfinae14.C: New.
+
 	* g++.dg/ext/vla10.C: New.
 
 2011-04-14  Richard Guenther  <rguenther@suse.de>
diff --git a/gcc/testsuite/g++.dg/cpp0x/sfinae14.C b/gcc/testsuite/g++.dg/cpp0x/sfinae14.C
new file mode 100644
index 0000000..305f96e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/sfinae14.C
@@ -0,0 +1,27 @@
+// PR c++/48557
+// { dg-options -std=c++0x }
+
+template<class T>
+struct add_rval_ref
+{
+  typedef T&& type;
+};
+
+template<>
+struct add_rval_ref<void>
+{
+  typedef void type;
+};
+
+template<class T>
+typename add_rval_ref<T>::type create();
+
+template<class T, class U,
+  class = decltype(create<T>() + create<U>())
+>
+char f(int);
+
+template<class, class>
+char (&f(...))[2];
+
+static_assert(sizeof(f<void, int>(0)) != 1, "Error");  // (a)
-- 
2.7.4