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SDL2 isn't drawing rectangles in Mac environment

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I can't get SDL to make any rectangles on my Mac. The program I wrote worked completely fine on a Windows computer, but whenever I call the SDL_FillRect function on my Mac, nothing appears on the screen. I suspect this may be caused by a compilation issue. I'm using SDL through Frameworks. Inserted below is my terminal command and my code:

g++ example.cpp -I/Library/Frameworks/SDL2.framework/Headers -F/Library/Frameworks -framework SDL2
	#include <SDL2/SDL.h>
#include <iostream>
#include <stdio.h>
	const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;
const int PLAYER_WIDTH = 20;
const int PLAYER_HEIGHT = 20;
SDL_Window* w = NULL;
SDL_Surface* s = NULL;
SDL_Renderer* r = NULL;
SDL_Rect BG = {0,0,SCREEN_WIDTH,SCREEN_HEIGHT};
	 
	bool init() {
	    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        printf("Couldn't initialize. error: %s\n", SDL_GetError() );
        return false;
    } else {
	        w = SDL_CreateWindow("test", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
	
        if(w == NULL) {
            printf("Couldn't make window. error:%s\n", SDL_GetError() );
            return false;
        } else {
            s = SDL_GetWindowSurface(w);
            r = SDL_CreateRenderer(w,-1,SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
            SDL_SetRenderDrawColor(r,0,0,0,0);
            return true;
        }
	    }
	}
	void close() {
    SDL_FreeSurface(s);
    SDL_DestroyWindow(w);
    SDL_DestroyRenderer(r);
    SDL_Quit();
	}
	class Player {
	    private:
        int x;
        int y;
        int xvel;
        int yvel;
        int acceleration;
        SDL_Rect collider;
	
    public:
	        bool landed;
	        Player() {
            x = 0;
            y = SCREEN_HEIGHT - PLAYER_HEIGHT;
            xvel = 0;
            yvel = 0;
            acceleration = -1;
            collider.x = x;
            collider.y = y;
            collider.w = PLAYER_WIDTH;
            collider.h = PLAYER_HEIGHT;            
            landed = true;
        }
	        int getx() {
            return x;
        }
	        int gety() {
            return y;
        }
	        void setx(int num) {
            x = num;
        }
	        void sety(int num) {
            y = num;
        }
	        void setyvel(int num) {
            yvel += num;
        }
	        void setxvel(int num) {
            xvel += num;
        }
	        void move() {
            x += xvel;
	            if( (y + PLAYER_HEIGHT) > SCREEN_HEIGHT) {
                
                y = SCREEN_HEIGHT - PLAYER_HEIGHT;
                yvel = 0;
                landed = true;
	            } else {
                if(landed != true) { //so sorry for the bad code, this was the only idea i had to debug "bouncing" of the player
                    y += yvel;
                    yvel = yvel - acceleration;
                }
                
            }
	            
            collider.x = x;
            collider.y = y;
        }
	        void render() {
            SDL_SetRenderDrawColor(r,255,255,255,255);
            SDL_RenderFillRect(r,&collider);
            SDL_SetRenderDrawColor(r,0,0,0,255);
        }
};
	
int main(int argc, char *argv[]) {
	bool quit = false;
SDL_Event e; //event for event polling
Player p;
int count = 0;
	    if(init() == false) {
	        printf("Init failed: %s\n", SDL_GetError());
	    } else {
        while(quit == false ) {
            while( SDL_PollEvent(&e) != 0) {
	                if(e.type == SDL_QUIT) {
                    quit = true;
                }
	
                
                if(e.type == SDL_KEYDOWN) {
	                    switch(e.key.keysym.sym) {
	                        case SDLK_LEFT: if(e.key.repeat == 0) { p.setxvel(-10); }
                        break;
	                        case SDLK_RIGHT: if(e.key.repeat == 0) { p.setxvel(10); }
                        break;
	                        case SDLK_UP:
	                        if(count < 5) {
                            p.setyvel(-3);
                            ++count;
                            }
                            p.landed = false;
                        
                        break;
	                    }
	                }
	                
	                if(e.type == SDL_KEYUP && e.key.repeat == 0) {
	                    switch(e.key.keysym.sym) {
	                        case SDLK_LEFT: p.setxvel(10);
                        break;
	                        case SDLK_RIGHT: p.setxvel(-10);
                        break;
	                        case SDLK_UP: count = 0;
                        break;
	                    }
	                }
	                
	            }
	            SDL_RenderClear(r);
            SDL_RenderFillRect(r,&BG);
            p.move();
            p.render();
            
	            SDL_RenderPresent(r);
        }
    }
	    close();

Please help me to get it working, I have no idea what's going on. I have SDL 2.0.7 and my Mac is OS X 10.10.3.

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