segfault with SDL2.0

pix.c

#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <inttypes.h>
#include <time.h>

#include <SDL.h>

int main(int argc, char* argv[]) {
	(void)(argc);
	(void)(argv);

	srand(time(NULL));

	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
		fprintf(stderr, "Cannot init SDL: %s\n", SDL_GetError());
		exit(1);
	}

	SDL_Window* window = SDL_CreateWindow(
		"Pixel renderer",
		SDL_WINDOWPOS_UNDEFINED,
		SDL_WINDOWPOS_UNDEFINED,
		800, 600,
		SDL_WINDOW_SHOWN);

	if (window == NULL) {
		fprintf(stderr, "Cannot open window: %s\n", SDL_GetError());
		exit(1);
	}

	SDL_Surface* surface = SDL_GetWindowSurface(window);
	SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);

	SDL_Event e;
	bool quit = false;
	bool pause = false;
	while (!quit) {
		while (SDL_PollEvent(&e) != 0) {
			if (e.type == SDL_QUIT) {
				quit = true;
			}

			switch (e.key.keysym.sym) {
			case SDLK_ESCAPE: quit = true;    break;
			case SDLK_SPACE:
				if (e.key.type == SDL_KEYDOWN) {
					pause = !pause;
					printf("pausing: %d\n", pause);
				}
				break;
			}
		}

		if (pause) {
			continue;
		}

		SDL_Delay(20);
		// uncomment this next line to prevent segfault.
		// Has something to do with the creation of the renderer on #35
		SDL_UpdateWindowSurface(window);
	}


	SDL_FreeSurface(surface);
	SDL_DestroyWindow(window);
	SDL_DestroyRenderer(renderer);
	SDL_Quit();
	return 0;
}