[PATCH 3.13 077/103] xattr: fix check for simultaneous glibc header inclusion

[Kamal Mostafa]

3.13.11.8 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Filipe Brandenburger <filbranden at google.com>

commit bfcfd44cce2774f19daeb59fb4e43fc9aa80e7b8 upstream.

The guard was introduced in commit ea1a8217b06b ("xattr: guard against
simultaneous glibc header inclusion") but it is using #ifdef to check
for a define that is either set to 1 or 0.  Fix it to use #if instead.

* Without this patch:

  $ { echo "#include <sys/xattr.h>"; echo "#include <linux/xattr.h>"; } | gcc -E -Iinclude/uapi - >/dev/null
  include/uapi/linux/xattr.h:19:0: warning: "XATTR_CREATE" redefined [enabled by default]
   #define XATTR_CREATE 0x1 /* set value, fail if attr already exists */
   ^
  /usr/include/x86_64-linux-gnu/sys/xattr.h:32:0: note: this is the location of the previous definition
   #define XATTR_CREATE XATTR_CREATE
   ^

* With this patch:

  $ { echo "#include <sys/xattr.h>"; echo "#include <linux/xattr.h>"; } | gcc -E -Iinclude/uapi - >/dev/null
  (no warnings)

Signed-off-by: Filipe Brandenburger <filbranden at google.com>
Acked-by: Serge E. Hallyn <serge.hallyn at ubuntu.com>
Cc: Allan McRae <allan at archlinux.org>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 include/uapi/linux/xattr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/xattr.h b/include/uapi/linux/xattr.h
index a63c146..f2765c1 100644
--- a/include/uapi/linux/xattr.h
+++ b/include/uapi/linux/xattr.h
@@ -13,7 +13,7 @@
 #ifndef _UAPI_LINUX_XATTR_H
 #define _UAPI_LINUX_XATTR_H
 
-#ifdef __UAPI_DEF_XATTR
+#if __UAPI_DEF_XATTR
 #define __USE_KERNEL_XATTR_DEFS
 
 #define XATTR_CREATE	0x1	/* set value, fail if attr already exists */
-- 
1.9.1