3 files changed, 15 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index 3bacde4257..a4b08b8d25 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Sat Sep 28 10:40:44 2002  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* 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.
+
 Sat Sep 28 09:50:03 2002  KONISHI Hiromasa <konishih@fd6.so-net.ne.jp>
 
 	* ext/extmk.rb: The condition judgment without necessity was deleted.
diff --git a/class.c b/class.c
index d55c37e991..316118bfe3 100644
--- a/class.c
+++ b/class.c
@@ -152,7 +152,12 @@ rb_make_metaclass(obj, super)
 	RCLASS(klass)->super = RBASIC(rb_class_real(RCLASS(obj)->super))->klass;
     }
     else {
-	RBASIC(klass)->klass = RBASIC(rb_class_real(super))->klass;
+	VALUE metasuper = RBASIC(rb_class_real(super))->klass;
+
+	/* metaclass of a superclass may be NULL at boot time */
+	if (metasuper) {
+	    RBASIC(klass)->klass;
+	}
     }
 
     return klass;
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);