diff --git a/src/vm.c b/src/vm.c
index 0a6d4af8d..86262650e 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -2834,6 +2834,7 @@ mrb_top_run(mrb_state *mrb, struct RProc *proc, mrb_value self, unsigned int sta
     return mrb_vm_run(mrb, proc, self, stack_keep);
   }
   if (mrb->c->ci == mrb->c->cibase) {
+    mrb->c->ci->env = NULL;
     return mrb_vm_run(mrb, proc, self, stack_keep);
   }
   ci = cipush(mrb);