1 files changed, 3 insertions, 0 deletions
diff --git a/hash.c b/hash.c
index 0e5abb78ef..31f22e74d6 100644
--- a/hash.c
+++ b/hash.c
@@ -1172,4 +1172,7 @@ Init_Hash()
     rb_define_singleton_method(envtbl,"value?", env_has_value, 1);
 
     rb_define_global_const("ENV", envtbl);
+
+    /* turn on premitive flag for the class */
+    FL_SET(cHash, FL_PRIMITIVE);
 }