Question

我刚刚使用SDL 1.2完成了一个俄罗斯方块克隆，现在我正在尝试使用SDL2制作更好的版本。但我得到了分段错误，我不知道为什么。

这是valgrind报告：

==9471== Memcheck, a memory error detector
==9471== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==9471== Using Valgrind-3.9.0 and LibVEX; rerun with -h for copyright info
==9471== Command: ./tetris
==9471== 
==9471== Thread 2:
==9471== Invalid read of size 8
==9471==    at 0xB4B57A9: ??? (in /usr/lib/x86_64-linux-gnu/nvidia/current/libGL.so.319.82)
==9471==    by 0x4E8094E: ??? (in /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0.1.0)
==9471==    by 0x4E799EA: SDL_CreateTexture (in /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0.1.0)
==9471==    by 0x4E79C6D: SDL_CreateTextureFromSurface (in /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0.1.0)
==9471==    by 0x401176: load_texture.3137.2439 
==9471==    by 0x401194: video_load_image.2436
==9471==    by 0x4011B6: block_image_load_all.2429
==9471==    by 0x4017BD: run_game_logic.2384
==9471==    by 0x541B061: start_thread (pthread_create.c:312)
==9471==    by 0x5715A3C: clone (clone.S:111)
==9471==  Address 0x8c0 is not stack'd, malloc'd or (recently) free'd
==9471== 
==9471== 
==9471== Process terminating with default action of signal 11 (SIGSEGV)
==9471==  Access not within mapped region at address 0x8C0
==9471==    at 0xB4B57A9: ??? (in /usr/lib/x86_64-linux-gnu/nvidia/current/libGL.so.319.82)
==9471==    by 0x4E8094E: ??? (in /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0.1.0)
==9471==    by 0x4E799EA: SDL_CreateTexture (in /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0.1.0)
==9471==    by 0x4E79C6D: SDL_CreateTextureFromSurface  (in /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0.1.0)
==9471==    by 0x401176: load_texture.3137.2439
==9471==    by 0x401194: video_load_image.2436
==9471==    by 0x4011B6: block_image_load_all.2429
==9471==    by 0x4017BD: run_game_logic.2384
==9471==    by 0x541B061: start_thread (pthread_create.c:312)
==9471==    by 0x5715A3C: clone (clone.S:111)
==9471==  If you believe this happened as a result of a stack
==9471==  overflow in your program's main thread (unlikely but
==9471==  possible), you can try to increase the size of the
==9471==  main thread stack using the --main-stacksize= flag.
==9471==  The main thread stack size used in this run was 8388608.

功能：

SDL_Texture *video_load_image(const char *file)
{
    return load_texture(file);
}

static SDL_Texture *load_texture(const char *path)
{
    SDL_Surface *surface;
    SDL_Texture *texture;

    if((surface = SDL_LoadBMP(path)) == NULL){
        puts("invalid path");
        return NULL;
    }

    texture = SDL_CreateTextureFromSurface(renderer, surface);
    SDL_FreeSurface(surface);

    return texture;
}

char *image_path[BLOCK_COUNT] = {
    "img/block_dark_cyan32.bmp", "img/block_dark_red32.bmp",
    "img/block_dark_brown32.bmp", "img/block_dark_magenta32.bmp",
    "img/block_dark_gray32.bmp", "img/block_dark_green32.bmp",
    "img/block_dark_blue32.bmp", 
    "img/block_wall32.bmp", "img/block_empty32.bmp"
};

SDL_Texture *textures[BLOCK_COUNT];

int block_image_load_all(void)
{
    for(int i = 0; i < BLOCK_COUNT; ++i){
        if((textures[i] = video_load_image(image_path[i])) == NULL){
            while(i > 0)
                video_free_image(textures[--i]);

            return ERROR;
        }
    }

    return SUCCESS;
}

这里导致分段错误的原因是什么？

更新：将渲染器切换为SDL_RENDERER_SOFTWARE解决了问题，但我想使用SDL_RENDERER_ACCELERATED

我不认为问题是驱动因素，因为我在其他程序中成功使用SDL_RENDERER_ACCELERATED。

Answer 1

确保使用SDL_CreateRender()将-1作为第二个参数，以便SDL自动选择使用有效的视频卡。

如果问题仍然存在，请更新您的视频卡驱动程序（之后重新启动计算机）。

评论是否仍然存在

Answer 2

看起来您没有释放代码中的字体。尝试：

TTF_CloseFont(TTF_Font *font);

使用完字体后，或者在几百帧后会导致分段错误。

使用SDL2加载纹理的分段错误

2 个答案: