buildroot/package/btrfs-progs/0002-configure-refactor-always_inline-detection.patch

From 1d99ae25bb1bd4879c6f20f607faf3040018ee84 Mon Sep 17 00:00:00 2001
From: Brendan Heading <brendanheading@gmail.com>
Date: Thu, 30 Jul 2015 15:44:52 +0100
Subject: [PATCH 2/3] configure: refactor always_inline detection

Use configure.ac to detect the availability of the always_inline glibc
macro, and define it only if it does not exist.

Signed-off-by: Brendan Heading <brendanheading@gmail.com>
---
 configure.ac | 1 +
 kerncompat.h | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index e936a10..d3d81a1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -41,6 +41,7 @@ AC_PATH_PROG([RMDIR], [rmdir], [rmdir])
 
 AC_CHECK_FUNCS([openat], [],
 	[AC_MSG_ERROR([cannot find openat() function])])
+AC_CHECK_DECLS([__always_inline])
 
 m4_ifndef([PKG_PROG_PKG_CONFIG],
   [m4_fatal([Could not locate the pkg-config autoconf
diff --git a/kerncompat.h b/kerncompat.h
index 8318665..757b9b4 100644
--- a/kerncompat.h
+++ b/kerncompat.h
@@ -32,7 +32,7 @@
 
 #include <features.h>
 
-#ifndef __GLIBC__
+#ifndef HAVE_DECL___ALWAYS_INLINE
 #define __always_inline __inline __attribute__ ((__always_inline__))
 #endif
 
-- 
2.4.3