diff --git a/include/mruby/class.h b/include/mruby/class.h
index 0afd331b0..58b648579 100644
--- a/include/mruby/class.h
+++ b/include/mruby/class.h
@@ -28,7 +28,7 @@ mrb_class(mrb_state *mrb, mrb_value v)
 {
   switch (mrb_type(v)) {
   case MRB_TT_FALSE:
-    if (v.value.p)
+    if (v.value.i)
       return mrb->false_class;
     return mrb->nil_class;
   case MRB_TT_TRUE: