diff --git a/diff-merges.c b/diff-merges.c
index c48a65f8de..225edd293b 100644
--- a/diff-merges.c
+++ b/diff-merges.c
@@ -41,16 +41,13 @@ int diff_merges_parse_opts(struct rev_info *revs, const char **argv)
 		revs->ignore_merges = 0;
 		revs->match_missing = 1;
 	} else if (!strcmp(arg, "-c")) {
-		revs->diff = 1;
 		revs->dense_combined_merges = 0;
 		revs->combine_merges = 1;
 	} else if (!strcmp(arg, "--cc")) {
-		revs->diff = 1;
 		set_dense_combined(revs);
 	} else if (!strcmp(arg, "--no-diff-merges")) {
 		suppress(revs);
 	} else if (!strcmp(arg, "--combined-all-paths")) {
-		revs->diff = 1;
 		revs->combined_all_paths = 1;
 	} else if ((argcount = parse_long_opt("diff-merges", argv, &optarg))) {
 		if (!strcmp(optarg, "off")) {
@@ -103,6 +100,7 @@ void diff_merges_setup_revs(struct rev_info *revs)
 	if (revs->combined_all_paths && !revs->combine_merges)
 		die("--combined-all-paths makes no sense without -c or --cc");
 	if (revs->combine_merges) {
+		revs->diff = 1;
 		/* Turn --cc/-c into -p --cc/-c when -p was not given */
 		if (!revs->diffopt.output_format)
 			revs->diffopt.output_format = DIFF_FORMAT_PATCH;