在macOS下链接SDL_image失败的技术求助

问题详情 #

我正在用SDL2和CodeLite开发简易2D游戏引擎，执行编译命令：

g++ src/*.cpp -o game -I include -L lib -lSDL2 -lSDL2_image

编译失败。本地已准备include文件夹存放SDL头文件，lib文件夹存放SDL2和SDL_image库文件。切换到CodeLite后，SDL可正常链接，但使用SDL_image时编译失败——已在Project settings -> Linker和Compiler选项卡配置了相同的头文件与库路径，仍报以下错误：

Undefined symbols for architecture arm64:
  "_TIFFClientOpen", referenced from:
      _IMG_LoadTIF_RW in libSDL2_image.a(IMG_tif.o)
  "_TIFFClose", referenced from:
      _IMG_LoadTIF_RW in libSDL2_image.a(IMG_tif.o)
  "_TIFFGetField", referenced from:
      _IMG_LoadTIF_RW in libSDL2_image.a(IMG_tif.o)
  "_TIFFReadRGBAImageOriented", referenced from:
      _IMG_LoadTIF_RW in libSDL2_image.a(IMG_tif.o)
  "_WebPDecodeRGBAInto", referenced from:
      _IMG_LoadWEBP_RW in libSDL2_image.a(IMG_webp.o)
  "_WebPDecodeRGBInto", referenced from:
      _IMG_LoadWEBP_RW in libSDL2_image.a(IMG_webp.o)
  "_WebPGetFeaturesInternal", referenced from:
      _IMG_LoadWEBP_RW in libSDL2_image.a(IMG_webp.o)
  "_jpeg_CreateCompress", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_CreateDecompress", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_calc_output_dimensions", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_destroy_compress", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_destroy_decompress", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_finish_compress", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_finish_decompress", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_read_header", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_read_scanlines", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_resync_to_restart", referenced from:
      _IMG_InitJPG in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_set_defaults", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_set_quality", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_start_compress", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_start_decompress", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_std_error", referenced from:
      _IMG_LoadJPG_RW in libSDL2_image.a(IMG_jpg.o)
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_jpeg_write_scanlines", referenced from:
      _IMG_SaveJPG_RW in libSDL2_image.a(IMG_jpg.o)
  "_png_create_info_struct", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_create_read_struct", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_create_write_struct", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_destroy_read_struct", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_destroy_write_struct", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_get_IHDR", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_get_PLTE", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_get_channels", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_get_io_ptr", referenced from:
      _png_read_data in libSDL2_image.a(IMG_png.o)
      _png_write_data in libSDL2_image.a(IMG_png.o)
  "_png_get_tRNS", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_get_valid", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_read_image", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_read_info", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_read_update_info", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_IHDR", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_set_PLTE", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_set_expand", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_gray_to_rgb", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_interlace_handling", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_longjmp_fn", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_set_packing", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_read_fn", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_rows", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_set_strip_16", referenced from:
      _IMG_LoadPNG_RW in libSDL2_image.a(IMG_png.o)
  "_png_set_tRNS", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_set_write_fn", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
  "_png_write_png", referenced from:
      _IMG_SavePNG_RW_libpng in libSDL2_image.a(IMG_png.o)
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

环境：M1 MacBook Air，macOS Monterey 12.6，CodeLite 16.6.9。

解决方案 #

报错原因是你使用的静态版SDL2_image库（从libSDL2_image.a可判断）没有自动链接它依赖的底层图像格式库（JPEG、PNG、TIFF、WebP），需要手动添加这些依赖：

1. 命令行编译修复 #

修改编译命令，按依赖顺序添加缺失的库（注意库的顺序：被依赖的库要放在后面）：

g++ src/*.cpp -o game -I include -L lib -lSDL2_image -lSDL2 -ljpeg -lpng -ltiff -lwebp

2. CodeLite配置修复 #

• 打开Project settings -> Linker -> Libraries
• 按以下顺序添加库：SDL2_image、SDL2、jpeg、png、tiff、webp
• 确保lib文件夹中存在对应ARM64版本的库文件（如libjpeg.a、libpng.a等），如果缺失，需下载适配M1芯片的版本放入lib目录

额外说明 #

如果使用动态版SDL2_image（.dylib文件），通常会自动处理依赖链，不会出现这类问题。如果静态库仍有问题，可尝试重新编译SDL2_image并确保编译时链接了所有图像格式库。

内容的提问来源于stack exchange，提问作者Antonin