Old SDL window should not be used after SDL_Quit

#include <SDL.h>

int main()
{
	int ret;
	SDL_Window *w1, *w2;
	Uint32 flags = SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN;
	int i, j;

	ret = SDL_Init(SDL_INIT_VIDEO);
	w1 = SDL_CreateWindow("my title", 100, 200, 100, 100, flags);
	i = SDL_GetWindowDisplayIndex(w1);
	SDL_Log("index: %d\n", i);
	SDL_Quit();
	ret = SDL_Init(SDL_INIT_VIDEO);
	w2 = SDL_CreateWindow("my title2", 100, 200, 100, 100, flags);

	j = SDL_GetWindowDisplayIndex(w2);
	SDL_Log("w2 index: %d\n", j);

	i = SDL_GetWindowDisplayIndex(w1);
	SDL_Log("w1 index: %d\n", i);
	SDL_Quit();


	return ret;
}