--- a/aclocal.m4
+++ b/aclocal.m4
@@ -7,16 +7,17 @@ builtin(include, build/autoconf/glib.m4)
 builtin(include, build/autoconf/nspr.m4)dnl
 builtin(include, build/autoconf/nss.m4)dnl
 builtin(include, build/autoconf/pkg.m4)dnl
 builtin(include, build/autoconf/freetype2.m4)dnl
 builtin(include, build/autoconf/codeset.m4)dnl
 builtin(include, build/autoconf/altoptions.m4)dnl
 builtin(include, build/autoconf/mozprog.m4)dnl
 builtin(include, build/autoconf/mozheader.m4)dnl
+builtin(include, build/autoconf/mozcommonheader.m4)dnl
 builtin(include, build/autoconf/acwinpaths.m4)dnl
 builtin(include, build/autoconf/lto.m4)dnl
 builtin(include, build/autoconf/gcc-pr49911.m4)dnl
 builtin(include, build/autoconf/frameptr.m4)dnl
 
 MOZ_PROG_CHECKMSYS()
 
 # Read the user's .mozconfig script.  We can't do this in

new file mode 100644
--- /dev/null
+++ b/build/autoconf/mozcommonheader.m4
@@ -0,0 +1,41 @@
+dnl ***** BEGIN LICENSE BLOCK *****
+dnl Version: MPL 1.1/GPL 2.0/LGPL 2.1
+dnl
+dnl The contents of this file are subject to the Mozilla Public License Version
+dnl 1.1 (the "License"); you may not use this file except in compliance with
+dnl the License. You may obtain a copy of the License at
+dnl http://www.mozilla.org/MPL/
+dnl
+dnl Software distributed under the License is distributed on an "AS IS" basis,
+dnl WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+dnl for the specific language governing rights and limitations under the
+dnl License.
+dnl
+dnl The Original Code is mozilla.org code.
+dnl
+dnl The Initial Developer of the Original Code is the
+dnl Mozilla Foundation <http://www.mozilla.org>
+dnl
+dnl Portions created by the Initial Developer are Copyright (C) 2009
+dnl the Initial Developer. All Rights Reserved.
+dnl
+dnl
+dnl Alternatively, the contents of this file may be used under the terms of
+dnl either of the GNU General Public License Version 2 or later (the "GPL"),
+dnl or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+dnl in which case the provisions of the GPL or the LGPL are applicable instead
+dnl of those above. If you wish to allow use of your version of this file only
+dnl under the terms of either the GPL or the LGPL, and not to allow others to
+dnl use your version of this file under the terms of the MPL, indicate your
+dnl decision by deleting the provisions above and replace them with the notice
+dnl and other provisions required by the GPL or the LGPL. If you do not delete
+dnl the provisions above, a recipient may use your version of this file under
+dnl the terms of any one of the MPL, the GPL or the LGPL.
+dnl
+dnl ***** END LICENSE BLOCK *****
+
+AC_DEFUN(MOZ_CHECK_COMMON_HEADERS,
+	MOZ_CHECK_HEADERS(sys/byteorder.h compat.h getopt.h sys/bitypes.h \
+        memory.h unistd.h gnu/libc-version.h nl_types.h malloc.h \
+        X11/XKBlib.h io.h cpuid.h)
+)

--- a/configure.in
+++ b/configure.in
@@ -3404,22 +3404,17 @@ dnl Checks for header files.
 dnl ========================================================
 AC_HEADER_DIRENT
 case "$target_os" in
 freebsd*|openbsd*)
 # for stuff like -lXshm
     CPPFLAGS="${CPPFLAGS} ${X_CFLAGS}"
     ;;
 esac
-MOZ_CHECK_HEADERS(sys/byteorder.h compat.h getopt.h)
-MOZ_CHECK_HEADERS(sys/bitypes.h memory.h unistd.h)
-MOZ_CHECK_HEADERS(gnu/libc-version.h nl_types.h)
-MOZ_CHECK_HEADERS(malloc.h)
-MOZ_CHECK_HEADERS(X11/XKBlib.h)
-MOZ_CHECK_HEADERS(io.h)
+MOZ_CHECK_COMMON_HEADERS
 
 dnl These are all the places some variant of statfs can be hiding.
 MOZ_CHECK_HEADERS(sys/statvfs.h sys/statfs.h sys/vfs.h sys/mount.h)
 
 dnl Quota support
 MOZ_CHECK_HEADERS(sys/quota.h sys/sysmacros.h)
 MOZ_CHECK_HEADERS(linux/quota.h)
 

--- a/js/src/aclocal.m4
+++ b/js/src/aclocal.m4
@@ -4,14 +4,15 @@ dnl The contents of this file are under 
 dnl 
 
 builtin(include, build/autoconf/pkg.m4)dnl
 builtin(include, build/autoconf/nspr.m4)dnl
 builtin(include, build/autoconf/altoptions.m4)dnl
 builtin(include, build/autoconf/moznbytetype.m4)dnl
 builtin(include, build/autoconf/mozprog.m4)dnl
 builtin(include, build/autoconf/mozheader.m4)dnl
+builtin(include, build/autoconf/mozcommonheader.m4)dnl
 builtin(include, build/autoconf/acwinpaths.m4)dnl
 builtin(include, build/autoconf/lto.m4)dnl
 builtin(include, build/autoconf/gcc-pr49911.m4)dnl
 builtin(include, build/autoconf/frameptr.m4)dnl
 
 MOZ_PROG_CHECKMSYS()

new file mode 100644
--- /dev/null
+++ b/js/src/build/autoconf/mozcommonheader.m4
@@ -0,0 +1,41 @@
+dnl ***** BEGIN LICENSE BLOCK *****
+dnl Version: MPL 1.1/GPL 2.0/LGPL 2.1
+dnl
+dnl The contents of this file are subject to the Mozilla Public License Version
+dnl 1.1 (the "License"); you may not use this file except in compliance with
+dnl the License. You may obtain a copy of the License at
+dnl http://www.mozilla.org/MPL/
+dnl
+dnl Software distributed under the License is distributed on an "AS IS" basis,
+dnl WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+dnl for the specific language governing rights and limitations under the
+dnl License.
+dnl
+dnl The Original Code is mozilla.org code.
+dnl
+dnl The Initial Developer of the Original Code is the
+dnl Mozilla Foundation <http://www.mozilla.org>
+dnl
+dnl Portions created by the Initial Developer are Copyright (C) 2009
+dnl the Initial Developer. All Rights Reserved.
+dnl
+dnl
+dnl Alternatively, the contents of this file may be used under the terms of
+dnl either of the GNU General Public License Version 2 or later (the "GPL"),
+dnl or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+dnl in which case the provisions of the GPL or the LGPL are applicable instead
+dnl of those above. If you wish to allow use of your version of this file only
+dnl under the terms of either the GPL or the LGPL, and not to allow others to
+dnl use your version of this file under the terms of the MPL, indicate your
+dnl decision by deleting the provisions above and replace them with the notice
+dnl and other provisions required by the GPL or the LGPL. If you do not delete
+dnl the provisions above, a recipient may use your version of this file under
+dnl the terms of any one of the MPL, the GPL or the LGPL.
+dnl
+dnl ***** END LICENSE BLOCK *****
+
+AC_DEFUN(MOZ_CHECK_COMMON_HEADERS,
+	MOZ_CHECK_HEADERS(sys/byteorder.h compat.h getopt.h sys/bitypes.h \
+        memory.h unistd.h gnu/libc-version.h nl_types.h malloc.h \
+        X11/XKBlib.h io.h cpuid.h)
+)

--- a/js/src/configure.in
+++ b/js/src/configure.in
@@ -3243,22 +3243,17 @@ dnl Checks for header files.
 dnl ========================================================
 AC_HEADER_DIRENT
 case "$target_os" in
 freebsd*)
 # for stuff like -lXshm
     CPPFLAGS="${CPPFLAGS} ${X_CFLAGS}"
     ;;
 esac
-MOZ_CHECK_HEADERS(sys/byteorder.h compat.h getopt.h)
-MOZ_CHECK_HEADERS(sys/bitypes.h memory.h unistd.h)
-MOZ_CHECK_HEADERS(gnu/libc-version.h nl_types.h)
-MOZ_CHECK_HEADERS(malloc.h)
-MOZ_CHECK_HEADERS(X11/XKBlib.h)
-MOZ_CHECK_HEADERS(io.h)
+MOZ_CHECK_COMMON_HEADERS
 
 dnl These are all the places some variant of statfs can be hiding.
 MOZ_CHECK_HEADERS(sys/statvfs.h sys/statfs.h sys/vfs.h sys/mount.h)
 
 dnl Quota support
 MOZ_CHECK_HEADERS(sys/quota.h)
 MOZ_CHECK_HEADERS(linux/quota.h)
 

--- a/xpcom/glue/SSE.cpp
+++ b/xpcom/glue/SSE.cpp
@@ -41,17 +41,17 @@
 
 namespace {
 
 // SSE.h has parallel #ifs which declare MOZILLA_SSE_HAVE_CPUID_DETECTION.
 // We can't declare these functions in the header file, however, because
 // <intrin.h> conflicts with <windows.h> on MSVC 2005, and some files want to
 // include both SSE.h and <windows.h>.
 
-#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)) && (defined(__i386__) || defined(__x86_64__))
+#ifdef HAVE_CPUID_H
 
 // cpuid.h is available on gcc 4.3 and higher on i386 and x86_64
 #include <cpuid.h>
 
 enum CPUIDRegister { eax = 0, ebx = 1, ecx = 2, edx = 3 };
 
 static bool
 has_cpuid_bit(unsigned int level, CPUIDRegister reg, unsigned int bit)

--- a/xpcom/glue/SSE.h
+++ b/xpcom/glue/SSE.h
@@ -155,17 +155,17 @@
   // It's ok to use SSE4.1 instructions based on the -march option.
   #define MOZILLA_PRESUME_SSE4_1 1
 #endif
 #ifdef __SSE4_2__
   // It's ok to use SSE4.2 instructions based on the -march option.
   #define MOZILLA_PRESUME_SSE4_2 1
 #endif
 
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+#ifdef HAVE_CPUID_H
   #define MOZILLA_SSE_HAVE_CPUID_DETECTION
 #endif
 
 #elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_AMD64))
 
 #if _MSC_VER >= 1400
   // MSVC 2005 or newer on x86 or amd64
   #define MOZILLA_SSE_HAVE_CPUID_DETECTION