diff --git a/include/xemmai/fiber.h b/include/xemmai/fiber.h
index 2641ff8..cbe6277 100644
--- a/include/xemmai/fiber.h
+++ b/include/xemmai/fiber.h
@@ -18,15 +18,6 @@ struct t_fiber
 {
 	struct t_internal
 	{
-#ifdef _WIN32
-		static void CALLBACK f_start(PVOID a_f)
-		{
-			t_object* bottom = nullptr;
-			v_current->v_stack_bottom = ⊥
-			reinterpret_cast<void(*)()>(a_f)();
-		}
-#endif
-
 		t_internal* v_next;
 		void* v_thread;
 		t_fiber* v_fiber;
diff --git a/src/fiber.cc b/src/fiber.cc
index 78780be..404a126 100644
--- a/src/fiber.cc
+++ b/src/fiber.cc
@@ -77,7 +77,12 @@ t_fiber::t_internal::t_internal(t_fiber* a_fiber, void(*a_f)()) : t_internal(a_f
 t_fiber::t_internal::t_internal(t_fiber* a_fiber, void(*a_f)()) : t_internal(a_fiber->v_stack, 2)
 {
 	v_fiber = a_fiber;
-	v_handle = CreateFiber(0, f_start, a_f);
+	v_handle = CreateFiber(0, [](PVOID a_f)
+	{
+		t_object* bottom = nullptr;
+		v_current->v_stack_bottom = &bottom;
+		reinterpret_cast<void(*)()>(a_f)();
+	}, a_f);
 }
 #endif