diff --git a/diff-index.c b/diff-index.c
index 86940123b3..8c9f60173b 100644
--- a/diff-index.c
+++ b/diff-index.c
@@ -11,7 +11,6 @@ COMMON_DIFF_OPTIONS_HELP;
 int main(int argc, const char **argv)
 {
 	struct rev_info rev;
-	int match_missing = 0;
 	int cached = 0;
 	int i;