Fixed GCC version for bswap intrinsics (#385)

Use gcc 4.8 for __builtin_bswap16

diff --git a/zutil.h b/zutil.h
index e34caddeaba7b65bab249e51147ac07cb9e4c8fa..5471d0719329bd45345e1ae4a4018ea77d7ee5c3 100644 (file)
--- a/zutil.h
+++ b/zutil.h
@@ -175,7 +175,7 @@ void ZLIB_INTERNAL   zng_cfree(void *opaque, void *ptr);
 #  define ZSWAP64(q) _byteswap_uint64(q)
 
 #elif defined(__Clang__) || (defined(__GNUC__) && \
-        (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 2)))
+        (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))
 #  define ZSWAP16(q) __builtin_bswap16(q)
 #  define ZSWAP32(q) __builtin_bswap32(q)
 #  define ZSWAP64(q) __builtin_bswap64(q)