* hash.c (rb_hash_become): Hash#become should check added

  self-assignment.

* class.c (rb_make_metaclass): metaclass of a superclass may be
  NULL at boot time.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@2903 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/hash.c b/hash.c
index 3c0aeab2b8..6e1c247ba4 100644
--- a/hash.c
+++ b/hash.c
@@ -575,6 +575,7 @@ static VALUE
 rb_hash_become(hash, hash2)
     VALUE hash, hash2;
 {
+    if (hash == hash2) return hash;
     hash2 = to_hash(hash2);
     rb_hash_clear(hash);
     st_foreach(RHASH(hash2)->tbl, replace_i, hash);