t.Fatal("locked OS thread on exit from TestCallbackPanic")
		}
	}()
	nestedCall(func() { panic("callback panic") })
	panic("nestedCall returned")
}

func testCallbackPanicLoop(t *testing.T) {
	// Make sure we don't blow out m->g0 stack.
	for i := 0; i < 100000; i++ {
		testCallbackPanic(t)
	}
}

func testCallbackPanicLocked(t *testing.T) {
	runtime.LockOSThread()
	defer runtime.UnlockOSThread()