}
}
-int run_diff_index(struct rev_info *revs, int cached, int match_missing)
+int run_diff_index(struct rev_info *revs, int cached)
{
int ret;
struct object *ent;
struct tree *tree;
const char *tree_name;
+ int match_missing = 0;
+
+ /*
+ * Backward compatibility wart - "diff-index -m" does
+ * not mean "do not ignore merges", but totally different.
+ */
+ if (!revs->ignore_merges)
+ match_missing = 1;
if (read_cache() < 0) {
perror("read_cache");