+static int new_parent(int idx)
+{
+ int i;
+ unsigned char *sha1 = parent_sha1[idx];
+ for (i = 0; i < idx; i++) {
+ if (!memcmp(parent_sha1[i], sha1, 20)) {
+ error("duplicate parent %s ignored", sha1_to_hex(sha1));
+ return 0;
+ }
+ }
+ return 1;
+}