show_worktree(): plug memory leak

The buffer allocated by shorten_unambiguous_ref() needs to be released.

Discovered by Coverity.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: dscho

builtin/worktree.c

@@ -414,9 +414,11 @@ static void show_worktree(struct worktree *wt, int path_maxlen, int abbrev_len)
 				find_unique_abbrev(wt->head_sha1, DEFAULT_ABBREV));
 		if (wt->is_detached)
 			strbuf_addstr(&sb, "(detached HEAD)");
-		else if (wt->head_ref)
-			strbuf_addf(&sb, "[%s]", shorten_unambiguous_ref(wt->head_ref, 0));
-		else
+		else if (wt->head_ref) {
+			char *ref = shorten_unambiguous_ref(wt->head_ref, 0);
+			strbuf_addf(&sb, "[%s]", ref);
+			free(ref);
+		} else
 			strbuf_addstr(&sb, "(error)");
 	}
 	printf("%s\n", sb.buf);