xattr: guard against simultaneous glibc header inclusion
If the glibc xattr.h header is included after the uapi header,
compilation fails due to an enum re-using a #define from the uapi
header.
Protect against this by guarding the define and enum inclusions against
each other.
(See https://lists.debian.org/debian-glibc/2014/03/msg00029.html
and https://sourceware.org/glibc/wiki/Synchronizing_Headers
for more information.)
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Allan McRae <allan@archlinux.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/uapi/linux/libc-compat.h b/include/uapi/linux/libc-compat.h
index 335e8a7..c140620 100644
--- a/include/uapi/linux/libc-compat.h
+++ b/include/uapi/linux/libc-compat.h
@@ -85,6 +85,12 @@
#endif /* _NETINET_IN_H */
+/* Definitions for xattr.h */
+#if defined(_SYS_XATTR_H)
+#define __UAPI_DEF_XATTR 0
+#else
+#define __UAPI_DEF_XATTR 1
+#endif
/* If we did not see any headers from any supported C libraries,
* or we are being included in the kernel, then define everything
@@ -98,6 +104,9 @@
#define __UAPI_DEF_IPV6_MREQ 1
#define __UAPI_DEF_IPPROTO_V6 1
+/* Definitions for xattr.h */
+#define __UAPI_DEF_XATTR 1
+
#endif /* __GLIBC__ */
#endif /* _UAPI_LIBC_COMPAT_H */