Allegro draw_sprite（）

#include <allegro.h>

BITMAP *Sprite;

int main(){
    allegro_init();
    install_keyboard();
    set_color_depth(16);
    set_gfx_mode( GFX_AUTODETECT, 640, 480, 0, 0);

    Sprite = load_bitmap( \"x.bmp\", NULL);

    acquire_screen();
    draw_sprite(screen, Sprite, 50, 50);
    release_screen();

    readkey();

    return 0;

}   
END_OF_MAIN();

AllegroTest.exe

al-gfx INFO: The driver will wait for vsync.
al-gfx INFO: set_gfx_card success for 640x480x16.
Assert failed at line 250 of c:\\users\\matthew\\desktop\\allegro\\4.2\\include\\allegro\\inline\\draw.inlThe thread \'Win32 Thread\' (0x137c) has exited with code -805306369 (0xcfffffff).
The thread \'Win32 Thread\' (0x25b8) has exited with code -805306369 (0xcfffffff).