+ /*
+ * If we have an entry in the index cache ("old"), then we want
+ * to make sure that it matches any entries in stage 2 ("first
+ * branch", aka "b").
+ */
+ if (old) {
+ if (!b || !same(old, b))
+ return -1;
+ }
+ merge = merge_entries(a, b, c);
+ if (merge)
+ return merged_entry(merge, old, dst);
+ if (old)
+ verify_uptodate(old);
+ count = 0;
+ if (a) { *dst++ = a; count++; }
+ if (b) { *dst++ = b; count++; }
+ if (c) { *dst++ = c; count++; }
+ return count;
+}