From b24290fb5bfba313dc7143aa29a7b161fd501997 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Mon, 11 Apr 2011 18:00:06 -0400
Subject: [PATCH] PR c++/48457, Core 1238

	PR c++/48457, Core 1238
	* call.c (reference_binding): Allow rvalue reference to bind to
	function lvalue.
	* tree.c (lvalue_kind): Functions are always lvalues.

From-SVN: r172282
---
 gcc/cp/ChangeLog                              |  7 ++++++
 gcc/cp/call.c                                 |  4 +++-
 gcc/cp/tree.c                                 |  4 +++-
 gcc/testsuite/ChangeLog                       |  4 ++++
 gcc/testsuite/g++.dg/cpp0x/rv-func.C          | 22 +++++++++++++++++++
 libstdc++-v3/ChangeLog                        |  4 ++++
 .../testsuite/20_util/is_convertible/value.cc |  2 +-
 7 files changed, 44 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/rv-func.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 1b8f87363af..10400516965 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2011-04-11  Jason Merrill  <jason@redhat.com>
+
+	PR c++/48457, Core 1238
+	* call.c (reference_binding): Allow rvalue reference to bind to
+	function lvalue.
+	* tree.c (lvalue_kind): Functions are always lvalues.
+
 2011-04-07  Jason Merrill  <jason@redhat.com>
 
 	PR c++/48500
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index 096fbbc3d9c..4d03646b444 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -1521,8 +1521,10 @@ reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
 	   actually occurs.  */
 	conv->need_temporary_p = true;
 
-      /* Don't allow binding of lvalues to rvalue references.  */
+      /* Don't allow binding of lvalues (other than function lvalues) to
+	 rvalue references.  */
       if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
+	  && TREE_CODE (to) != FUNCTION_TYPE
           && !(flags & LOOKUP_PREFER_RVALUE))
 	conv->bad_p = true;
 
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index 3594ae42dd5..d6b6197cbe2 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -73,7 +73,9 @@ lvalue_kind (const_tree ref)
       if (TYPE_REF_IS_RVALUE (TREE_TYPE (ref))
 	  && TREE_CODE (ref) != PARM_DECL
 	  && TREE_CODE (ref) != VAR_DECL
-	  && TREE_CODE (ref) != COMPONENT_REF)
+	  && TREE_CODE (ref) != COMPONENT_REF
+	  /* Functions are always lvalues.  */
+	  && TREE_CODE (TREE_TYPE (TREE_TYPE (ref))) != FUNCTION_TYPE)
 	return clk_rvalueref;
 
       /* lvalue references and named rvalue references are lvalues.  */
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index dee6793d931..3812feff89a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2011-04-11  Jason Merrill  <jason@redhat.com>
+
+	* g++.dg/cpp0x/rv-func.C: New.
+
 2011-04-11  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* gcc.dg/torture/pr47917.c: Define _ISO_C_SOURCE=19990L for
diff --git a/gcc/testsuite/g++.dg/cpp0x/rv-func.C b/gcc/testsuite/g++.dg/cpp0x/rv-func.C
new file mode 100644
index 00000000000..db142961128
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/rv-func.C
@@ -0,0 +1,22 @@
+// PR c++/48457, Core 1238
+// { dg-options -std=c++0x }
+
+template<class T>
+T&& create();
+
+template<class T, class Arg>
+void test() {
+  T t(create<Arg>());
+  (void) t;
+}
+
+void f (void (&)());
+void f (void (&&)());
+
+int main() {
+  test<void(&)(), void()>();
+  test<void(&&)(), void()>();
+  // This call should choose the lvalue reference overload.
+  // { dg-final { scan-assembler-not "_Z1fOFvvE" } }
+  f(create<void()>());
+}
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index c4ed61f5376..5768ea60708 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,7 @@
+2011-04-08  Jason Merrill  <jason@redhat.com>
+
+	* testsuite/20_util/is_convertible/value.cc: Adjust.
+
 2011-04-11  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	* testsuite/25_algorithms/inplace_merge/moveable.cc: Actually run
diff --git a/libstdc++-v3/testsuite/20_util/is_convertible/value.cc b/libstdc++-v3/testsuite/20_util/is_convertible/value.cc
index f6282a90196..fc6007ac555 100644
--- a/libstdc++-v3/testsuite/20_util/is_convertible/value.cc
+++ b/libstdc++-v3/testsuite/20_util/is_convertible/value.cc
@@ -93,7 +93,7 @@ void test01()
 	                                     const volatile int&>(false)) );
   VERIFY( (test_relationship<is_convertible, volatile int,
 	                                     volatile int&>(false)) );
-  VERIFY( (test_relationship<is_convertible, int(int), int(&)(int)>(false)) );
+  VERIFY( (test_relationship<is_convertible, int(int), int(&)(int)>(true)) );
 
   VERIFY( (test_relationship<is_convertible, int&, ExplicitClass>(false)) );
   VERIFY( (test_relationship<is_convertible, void*, ExplicitClass>(false)) );
-- 
2.30.2