[PATCH] ewah/bitmap: silence warning about MASK macro redefinition

From: Eric Sunshine <sunshine@sunshineco.com>
Date: Jun 2, 2015, 21:47 UTC
Message-ID: <1433281675-24893-1-git-send-email-sunshine@sunshineco.com>

On PowerPC Mac OS X (10.5.8 "Leopard" with Xcode 3.1), system header /usr/include/ppc/param.h[1] pollutes the preprocessor namespace with a macro generically named MASK. This conflicts with the same-named macro in ewah/bitmap.c.

[1]: Included indirectly via:
     git-compat-util.h ->
     sys/sysctl.h ->
     sys/ucred.h ->
     sys/param.h ->
     machine/param.h ->
     ppc/param.h

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
---

The alternative is to rename MASK in ewah/bitmap.c to something less generic, resulting in a slightly more noisy patch. I chose the #undef approach since it's a relatively common idiom to #undef a macro before #defining it in order to avoid exactly this sort of redefinition problem.

 ewah/bitmap.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/ewah/bitmap.c b/ewah/bitmap.c
index 710e58c..b31cf75 100644
--- a/ewah/bitmap.c
+++ b/ewah/bitmap.c
@@ -20,6 +20,8 @@
 #include "git-compat-util.h"
 #include "ewok.h"
 
+#undef MASK
+#undef BLOCK
 #define MASK(x) ((eword_t)1 << (x % BITS_IN_WORD))
 #define BLOCK(x) (x / BITS_IN_WORD)

-- 
2.4.2.598.gb4379f4