Merge branch 'jc/longer-disambiguation-fix'

"git rev-parse --short" and friends failed to disambiguate two
objects with object names that share common prefix longer than 32
characters, which has been fixed.

* jc/longer-disambiguation-fix:
  abbrev: allow extending beyond 32 chars to disambiguate

Author: gitster

object-name.c

@@ -703,7 +703,7 @@ static int extend_abbrev_len(const struct object_id *oid,
 	while (mad->hex[i] && mad->hex[i] == get_hex_char_from_oid(oid, i))
 		i++;
 
-	if (i < GIT_MAX_RAWSZ && i >= mad->cur_len)
+	if (mad->hex[i] && i >= mad->cur_len)
 		mad->cur_len = i + 1;
 
 	return 0;