[PATCH] Cleanly redefine (v)snprintf when needed.

[Benoit Sigoure <tsunanet@gmail.com>]

When we detect that vsnprintf / snprintf are broken, we #define them to
an alternative implementation.  On OS X, stdio.h already #define's them,
which causes a warning to be issued at the point we re-define them in
`git-compat-util.h'.
---
 git-compat-util.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/git-compat-util.h b/git-compat-util.h
index cbd86c3..614a5e9 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -480,9 +480,15 @@ extern FILE *git_fopen(const char*, const char*);
 #endif
 
 #ifdef SNPRINTF_RETURNS_BOGUS
+#ifdef snprintf
+#undef snprintf
+#endif
 #define snprintf git_snprintf
 extern int git_snprintf(char *str, size_t maxsize,
 			const char *format, ...);
+#ifdef vsnprintf
+#undef vsnprintf
+#endif
 #define vsnprintf git_vsnprintf
 extern int git_vsnprintf(char *str, size_t maxsize,
 			 const char *format, va_list ap);
-- 
1.9.rc1.1.g186f0be.dirty