From 57abd19f9dec553a2f6ad133076a364ab1ec1c2a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafael=20=C3=81vila=20de=20Esp=C3=ADndola?=
 <respindola@mozilla.com>
Date: Wed, 28 Sep 2011 17:49:18 -0400
Subject: [PATCH] Bug 689609 - Move the changes back in. Needs a clobber.
 r=re-revert.

---
 configure.in | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/configure.in b/configure.in
index 49046aa572e..ba5b608975d 100644
--- a/configure.in
+++ b/configure.in
@@ -2824,24 +2824,28 @@ fi
 
 AC_SUBST(_MOZ_RTTI_FLAGS_ON)
 
-dnl Check whether we can use gcc's c++0x mode
+dnl Check whether we can use gcc's c++0x mode. We check for some basic
+dnl features that we need.
 AC_LANG_CPLUSPLUS
 
 if test "$GNU_CXX"; then
     _SAVE_CXXFLAGS=$CXXFLAGS
     CXXFLAGS="$CXXFLAGS -std=gnu++0x"
 
-    if test -z "$_MOZ_USE_RTTI"; then
-        CXXFLAGS="$CXXFLAGS $_MOZ_RTTI_FLAGS"
-        AC_CACHE_CHECK(for gcc c++0x headers bug without rtti,
-            ac_cv_cxx0x_headers_bug,
-            [AC_TRY_COMPILE([#include <memory>], [],
-                            ac_cv_cxx0x_headers_bug="no",
-                            ac_cv_cxx0x_headers_bug="yes")])
-        CXXFLAGS="$_SAVE_CXXFLAGS"
-        if test "$ac_cv_cxx0x_headers_bug" = "no"; then
-            CXXFLAGS="$CXXFLAGS -std=gnu++0x"
-        fi
+    CXXFLAGS="$CXXFLAGS $_MOZ_RTTI_FLAGS"
+    AC_CACHE_CHECK(for c++0x support,
+        ac_cv_cxx0x_support,
+        [AC_TRY_COMPILE([#include <memory>
+                         #include <utility>
+                         void f(int&&);], [
+                           int a;
+                           f(std::move(a));
+                        ],
+                        ac_cv_cxx0x_support="yes",
+                        ac_cv_cxx0x_support="no")])
+    CXXFLAGS="$_SAVE_CXXFLAGS"
+    if test "$ac_cv_cxx0x_support" = "yes"; then
+        CXXFLAGS="$CXXFLAGS -std=gnu++0x"
     fi
 fi