Add endianness configuration block for GCC.
Previously GCC using libc++ would just leak endian.h for every
include.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@247827 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/__config b/include/__config
index 7667500..e951f9b 100644
--- a/include/__config
+++ b/include/__config
@@ -64,6 +64,16 @@
#endif // __BIG_ENDIAN__
#endif // __BIG_ENDIAN__
+#ifdef __BYTE_ORDER__
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define _LIBCPP_LITTLE_ENDIAN 1
+#define _LIBCPP_BIG_ENDIAN 0
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#define _LIBCPP_LITTLE_ENDIAN 0
+#define _LIBCPP_BIG_ENDIAN 1
+#endif // __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#endif // __BYTE_ORDER__
+
#ifdef __FreeBSD__
# include <sys/endian.h>
# if _BYTE_ORDER == _LITTLE_ENDIAN
