xdiff: avoid more compiler warnings with XDL_FAST_HASH on 32-bit machines
Hide literals that can cause compiler warnings for 32-bit architectures in expressions that evaluate to small numbers there. Some compilers warn that 0x0001020304050608 won't fit into a 32-bit long, others that shifting right by 56 bits clears a 32-bit value completely. The correct values are calculated in the 64-bit case, which is all that matters in this if-branch. Reported-by: Øyvind A. Holm <sunny@sunbase.org> Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Acked-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe committed
May 22, 2012 at 22:36 UTC
7e356a979459092d10450e66d8512381e89c2570
1 file changed
+7
-1
xdiff/xutils.c
+7
-1
@@ -301,7 +301,13 @@ static inline long count_masked_bytes(unsigned long mask)
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* that works for the bytemasks without having to
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* mask them first.
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*/
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- return mask * 0x0001020304050608 >> 56;
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+ /*
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+ * return mask * 0x0001020304050608 >> 56;
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+ *
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+ * Doing it like this avoids warnings on 32-bit machines.
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+ */
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+ long a = (REPEAT_BYTE(0x01) / 0xff + 1);
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+ return mask * a >> (sizeof(long) * 7);
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} else {
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/*
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* Modified Carl Chatfield G+ version for 32-bit *