1 files changed, 1 insertions, 1 deletions
diff --git a/hash.c b/hash.c
index db70939505..004ee920e3 100644
--- a/hash.c
+++ b/hash.c
@@ -31,7 +31,7 @@
     ((klass = has_extra_methods(rb_obj_class(hash))) != 0) || \
     FL_TEST((hash), FL_EXIVAR|FL_TAINT|HASH_PROC_DEFAULT) || \
     !NIL_P(RHASH_IFNONE(hash)))
-#define HASH_REJECT_COPY_EXTRA_STATES 1
+#define HASH_REJECT_COPY_EXTRA_STATES 0
 
 static VALUE
 has_extra_methods(VALUE klass)