1 files changed, 6 insertions, 6 deletions

diff --git a/src/gc.c b/src/gc.c
index d84f44377..69e36640d 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -983,7 +983,7 @@ mrb_field_write_barrier(mrb_state *mrb, struct RBasic *obj, struct RBasic *value
   gc_assert(!is_dead(mrb, value) && !is_dead(mrb, obj));
   gc_assert(is_generational(mrb) || mrb->gc_state != GC_STATE_NONE);
 
-  if (is_minor_gc(mrb) || mrb->gc_state == GC_STATE_MARK) {
+  if (is_generational(mrb) || mrb->gc_state == GC_STATE_MARK) {
     add_gray_list(mrb, value);
   }
   else {
@@ -1188,13 +1188,13 @@ gc_generational_mode_get(mrb_state *mrb, mrb_value self)
 static mrb_value
 gc_generational_mode_set(mrb_state *mrb, mrb_value self)
 {
-  mrb_value enable;
+  int enable;
 
-  mrb_get_args(mrb, "o", &enable);
-  if (mrb->is_generational_gc_mode != mrb_test(enable))
-    change_gen_gc_mode(mrb, mrb_test(enable));
+  mrb_get_args(mrb, "b", &enable);
+  if (mrb->is_generational_gc_mode != enable)
+    change_gen_gc_mode(mrb, enable);
 
-  if (mrb_test(enable))
+  if (enable)
     return mrb_true_value();
   else
     return mrb_false_value();