diff --git a/cont.c b/cont.c
index 95f2de9b87..7a24ec5e53 100644
--- a/cont.c
+++ b/cont.c
@@ -1833,10 +1833,8 @@ rb_fiber_yield(int argc, const VALUE *argv)
 }
 
 void
-rb_fiber_reset_root_local_storage(VALUE thval)
+rb_fiber_reset_root_local_storage(rb_thread_t *th)
 {
-    rb_thread_t *th = rb_thread_ptr(thval);
-
     if (th->root_fiber && th->root_fiber != th->ec->fiber_ptr) {
 	th->ec->local_storage = th->root_fiber->cont.saved_ec.local_storage;
     }
diff --git a/internal.h b/internal.h
index e10fe670d7..8510ed2d1e 100644
--- a/internal.h
+++ b/internal.h
@@ -1374,9 +1374,10 @@ VALUE rb_complex_sqrt(VALUE x);
 VALUE rb_dbl_complex_polar_pi(double abs, double ang);
 VALUE rb_complex_pow(VALUE self, VALUE other);
 
+struct rb_thread_struct;
 /* cont.c */
 VALUE rb_obj_is_fiber(VALUE);
-void rb_fiber_reset_root_local_storage(VALUE);
+void rb_fiber_reset_root_local_storage(struct rb_thread_struct *);
 void ruby_register_rollback_func_for_ensure(VALUE (*ensure_func)(ANYARGS), VALUE (*rollback_func)(ANYARGS));
 
 /* debug.c */
diff --git a/vm.c b/vm.c
index f7d4b65f67..f487bd881a 100644
--- a/vm.c
+++ b/vm.c
@@ -2201,7 +2201,7 @@ ruby_vm_destruct(rb_vm_t *vm)
 	struct rb_objspace *objspace = vm->objspace;
 	vm->main_thread = 0;
 	if (th) {
-	    rb_fiber_reset_root_local_storage(th->self);
+	    rb_fiber_reset_root_local_storage(th);
 	    thread_free(th);
 	}
 	rb_vm_living_threads_init(vm);