diff --git a/commit.c b/commit.c
index 97205bfb2c..67e11d7a4f 100644
--- a/commit.c
+++ b/commit.c
@@ -438,13 +438,13 @@ static int add_merge_info(enum cmit_fmt fmt, char *buf, const struct commit *com
 
 	while (parent) {
 		struct commit *p = parent->item;
+		const char *hex = abbrev
+			? find_unique_abbrev(p->object.sha1, abbrev)
+			: sha1_to_hex(p->object.sha1);
+		char *dots = (abbrev && strlen(hex) != 40) ? "..." : "";
 		parent = parent->next;
 
-		offset += sprintf(buf + offset,
-				  abbrev ? " %s..." : " %s",
-				  abbrev
-				  ? find_unique_abbrev(p->object.sha1, abbrev)
-				  : sha1_to_hex(p->object.sha1));
+		offset += sprintf(buf + offset, " %s%s", hex, dots);
 	}
 	buf[offset++] = '\n';
 	return offset;