ewah: fix building with gcc < 3.4.0

The __builtin_ctzll function was added in gcc 3.4.0.
This extends the check for gcc so that use of __builtin_ctzll is only
enabled if gcc >= 3.4.0.

Signed-off-by: Tom G. Christensen <tgc@statsbiblioteket.dk>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/ewah/ewok.h b/ewah/ewok.h
index 43adeb5c6893381918ea948efa70b4756f831583..4b95847680fed3d534309b100fe00e3cdca5cb21 100644 (file)
--- a/ewah/ewok.h
+++ b/ewah/ewok.h
@@ -47,7 +47,8 @@ static inline uint32_t ewah_bit_popcount64(uint64_t x)
        return (x * 0x0101010101010101ULL) >> 56;
 }
 
-#ifdef __GNUC__
+/* __builtin_ctzll was not available until 3.4.0 */
+#if defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3  && __GNUC_MINOR > 3))
 #define ewah_bit_ctz64(x) __builtin_ctzll(x)
 #else
 static inline int ewah_bit_ctz64(uint64_t x)