未解决的外部符号,即使我认为我正确链接(MSVC)

Question

我有一个使用SDL作为外部库的项目.该项目使用_SDL_WM_SetCaption,_SDL_FillRect或_SDL_MapRGBA等函数.我已告诉链接器包含两个库SDL.lib和SDLmain.lib并告诉它查看放置这些库的文件夹.我还用dumpbin.exe检查了库文件,函数就在那里.但它仍然无法编译/链接？为什么？有人有主意吗？

编辑:这是链接器/编译器错误的示例输出:

14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_WM_SetCaption referenced in function "public: void __thiscall SDLGLEngine::SetTitle(char *)" (?SetTitle@SDLGLEngine@@QAEXPAD@Z)
14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_FillRect referenced in function "public: bool __thiscall SDLGLEngine::Init(int,int,int,bool)" (?Init@SDLGLEngine@@QAE_NHHH_N@Z)
14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_MapRGBA referenced in function "public: bool __thiscall SDLGLEngine::Init(int,int,int,bool)" (?Init@SDLGLEngine@@QAE_NHHH_N@Z)
14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_SetVideoMode referenced in function "public: bool __thiscall SDLGLEngine::Init(int,int,int,bool)" (?Init@SDLGLEngine@@QAE_NHHH_N@Z)
14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_GL_SetAttribute referenced in function "public: bool __thiscall SDLGLEngine::Init(int,int,int,bool)" (?Init@SDLGLEngine@@QAE_NHHH_N@Z)
14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_Quit referenced in function "public: bool __thiscall SDLGLEngine::Init(int,int,int,bool)" (?Init@SDLGLEngine@@QAE_NHHH_N@Z)
14>libtestd.lib(sdlgl.obj) : error LNK2019: unresolved external symbol _SDL_Init referenced in function "public: bool __thiscall SDLGLEngine::Init(int,int,int,bool)" (?Init@SDLGLEngine@@QAE_NHHH_N@Z)

Answer 1

可能的原因:

• sdl.lib和sdlmain.lib设置未添加到依赖项列表中
• 它们的位置未添加到链接器所在的目录列表中
• 你有不匹配的32和64位版本的库.