merge-base: teach "--fork-point" mode

diff --git a/git-compat-util.h b/git-compat-util.h
index ff193f4aa236727cc9b87ddbaeac1975b8c40fa7..cc4ba4d18f15f72a7e7d2d12e2fa7b51f6a2a3e1 100644 (file)
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -303,6 +303,13 @@ extern char *gitbasename(char *);
 #endif
 #endif
 
+/* The sentinel attribute is valid from gcc version 4.0 */
+#if defined(__GNUC__) && (__GNUC__ >= 4)
+#define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
+#else
+#define LAST_ARG_MUST_BE_NULL
+#endif
+
 #include "compat/bswap.h"
 
 #ifdef USE_WILDMATCH