ewah: fix building with gcc < 3.4.0

tgc · gitster · commit bd4e8822da3b · 2015-02-04T10:45:31.000-08:00
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 &gt;= 3.4.0.

Signed-off-by: Tom G. Christensen &lt;tgc@statsbiblioteket.dk&gt;
Reviewed-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git 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)

Original file line number	Diff line number	Diff line change
`@@ -47,7 +47,8 @@ static inline uint32_t ewah_bit_popcount64(uint64_t x)`
`47`	`47`	`return (x * 0x0101010101010101ULL) >> 56;`
`48`	`48`	`}`
`49`	`49`
`50`		`-#ifdef __GNUC__`
	`50`	`+/* __builtin_ctzll was not available until 3.4.0 */`
	`51`	`+#if defined(__GNUC__) && (__GNUC__ > 3 \|\| (__GNUC__ == 3 && __GNUC_MINOR > 3))`
`51`	`52`	`#define ewah_bit_ctz64(x) __builtin_ctzll(x)`
`52`	`53`	`#else`
`53`	`54`	`static inline int ewah_bit_ctz64(uint64_t x)`