鏈接庫中對SDL2函數的未定義引用（代碼：: Blocks）

Question

我已經創建了一個使用SDL2的靜態庫，但是在另一個項目中使用它時遇到了麻煩。 庫中引用的所有SDL2函數都會引發未定義的引用錯誤。 我可以在靜態庫項目的單元測試中使用SDL2，因此必須正確設置它...對嗎？ 我將-lSDL2等鏈接到與它正在工作的其他項目（包括單元測試）相同的鏈接。 這還不夠嗎？

我的鏈接器設置如下所示： Code :: Blocks中的鏈接器設置

這是構建日志：

    -------------- Build: Debug in sdl_frame_sample (compiler: GNU GCC Compiler)---------------

g++ -Wall -fexceptions -g -std=c++11 -Wextra -Wall -I../../sdl-frame/sdl_frame/include -I../../sdl-frame/sdl_frame/include/box2d -Iinclude -I/home/yeti/Programs/gtest-1.7.0/include -c /home/yeti/Documents/codes/sdl_frame_samples/sdl_frame_sample/main.cpp -o obj/Debug/main.o
g++ -Wall -fexceptions -g -std=c++11 -Wextra -Wall -I../../sdl-frame/sdl_frame/include -I../../sdl-frame/sdl_frame/include/box2d -Iinclude -I/home/yeti/Programs/gtest-1.7.0/include -c /home/yeti/Documents/codes/sdl_frame_samples/sdl_frame_sample/src/sample_game_t.cpp -o obj/Debug/src/sample_game_t.o
g++ -Wall -fexceptions -g -std=c++11 -Wextra -Wall -I../../sdl-frame/sdl_frame/include -I../../sdl-frame/sdl_frame/include/box2d -Iinclude -I/home/yeti/Programs/gtest-1.7.0/include -c /home/yeti/Documents/codes/sdl_frame_samples/sdl_frame_sample/src/sample_world_t.cpp -o obj/Debug/src/sample_world_t.o
g++ -L../sdl-frame/sdl_frame/bin/Debug -L/home/yeti/Programs/gtest-1.7.0 -o bin/Debug/sdl_frame_sample obj/Debug/main.o obj/Debug/src/sample_game_t.o obj/Debug/src/sample_world_t.o  -lSDL2main -lSDL2 -lSDL2_image -lSDL2_ttf  ../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a /home/yeti/Programs/gtest-1.7.0/libgtest.a
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_t.o): In function `game_t::~game_t()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:31: undefined reference to `SDL_Quit'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:32: undefined reference to `TTF_Quit'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_t.o): In function `game_t::init()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:40: undefined reference to `SDL_Init'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:42: undefined reference to `SDL_GetError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:48: undefined reference to `TTF_Init'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:50: undefined reference to `SDL_GetError'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_t.o): In function `game_t::start()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:87: undefined reference to `SDL_LogError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:93: undefined reference to `SDL_LogError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:121: undefined reference to `SDL_LogError'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_t.o): In function `game_t::add_world(game_world_t*)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:155: undefined reference to `SDL_LogError'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_t.o): In function `game_t::add_hud(hud_t*)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_t.cpp:166: undefined reference to `SDL_LogError'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_timer_t.o): In function `game_timer_t::start()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_timer_t.cpp:23: undefined reference to `SDL_GetTicks'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_timer_t.o): In function `game_timer_t::resume()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_timer_t.cpp:45: undefined reference to `SDL_GetTicks'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_timer_t.o): In function `game_timer_t::pause()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_timer_t.cpp:58: undefined reference to `SDL_GetTicks'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_timer_t.o): In function `game_timer_t::get_ticks()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_timer_t.cpp:77: undefined reference to `SDL_GetTicks'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_window_t.o): In function `game_window_t::init(std::string, int, int, unsigned int)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:34: undefined reference to `SDL_CreateWindow'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:37: undefined reference to `SDL_GetError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:42: undefined reference to `SDL_CreateRenderer'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:45: undefined reference to `SDL_GetError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:46: undefined reference to `SDL_DestroyWindow'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_window_t.o): In function `game_window_t::render()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:62: undefined reference to `SDL_SetRenderDrawColor'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:63: undefined reference to `SDL_RenderClear'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:87: undefined reference to `SDL_RenderPresent'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_window_t.o): In function `game_window_t::set_position(int, int)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:143: undefined reference to `SDL_SetWindowPosition'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_window_t.o): In function `game_window_t::free()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:148: undefined reference to `SDL_DestroyRenderer'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/game_window_t.cpp:150: undefined reference to `SDL_DestroyWindow'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_world_t.o): In function `game_world_t::update_game_objects(unsigned int)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/world/game_world_t.cpp:93: undefined reference to `SDL_LogError'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(world_image_t.o): In function `world_image_t::init(std::string)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/world/world_image_t.cpp:23: undefined reference to `SDL_LogError'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(asset_manager_t.o): In function `asset_manager_t::~asset_manager_t()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:16: undefined reference to `TTF_CloseFont'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(asset_manager_t.o): In function `asset_manager_t::load_text_texture(std::string, std::string, int, SDL_Color)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:42: undefined reference to `TTF_OpenFont'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(asset_manager_t.o): In function `asset_manager_t::load_texture_from_surface(SDL_Surface*, SDL_Renderer*)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:143: undefined reference to `SDL_GetError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:148: undefined reference to `SDL_CreateTextureFromSurface'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:151: undefined reference to `SDL_GetError'
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:155: undefined reference to `SDL_FreeSurface'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(asset_manager_t.o): In function `asset_manager_t::load_texture_from_text(_TTF_Font*, std::string, SDL_Color)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:164: undefined reference to `TTF_RenderText_Solid'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(asset_manager_t.o): In function `asset_manager_t::load_texture_from_image(std::string)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/asset_manager_t.cpp:177: undefined reference to `IMG_Load'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_texture_t.o): In function `game_texture_t::render(float, float, float, float)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/game_texture_t.cpp:27: undefined reference to `SDL_RenderCopy'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_texture_t.o): In function `game_texture_t::render(SDL_Rect*, SDL_Rect*)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/game_texture_t.cpp:37: undefined reference to `SDL_RenderCopy'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_texture_t.o): In function `game_texture_t::render(SDL_Rect*, double, SDL_Point*, SDL_Rect*)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/game_texture_t.cpp:58: undefined reference to `SDL_RenderCopyEx'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(game_texture_t.o): In function `game_texture_t::get_texture_dimensions(texture_dimensions_t&)':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/game_texture_t.cpp:68: undefined reference to `SDL_QueryTexture'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(tracked_SDL_Texture.o): In function `tracked_SDL_Texture::~tracked_SDL_Texture()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/asset_management/tracked_SDL_Texture.cpp:10: undefined reference to `SDL_DestroyTexture'
../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a(controller_t.o): In function `controller_t::refresh()':
/home/yeti/Documents/codes/sdl-frame/sdl_frame/src/controller_t.cpp:20: undefined reference to `SDL_PollEvent'
collect2: error: ld returned 1 exit status
Process terminated with status 1 (0 minute(s), 0 second(s))
42 error(s), 0 warning(s) (0 minute(s), 0 second(s))

任何幫助表示贊賞。 我已經堅持了一段時間:(

Answer 1

我設法解決了這個問題。 似乎是導致問題的鏈接順序。 sdl_frame.a需要在SDL2等之前鏈接。默認情況下，Code :: blocks在“鏈接庫”之前執行“其他鏈接器選項”，因此順序是錯誤的。

舊訂單：

g++ -L../sdl-frame/sdl_frame/bin/Debug -L/home/yeti/Programs/gtest-1.7.0 -o bin/Debug/sdl_frame_sample obj/Debug/main.o obj/Debug/src/sample_game_t.o obj/Debug/src/sample_world_t.o  -lSDL2main -lSDL2 -lSDL2_image -lSDL2_ttf  ../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a /home/yeti/Programs/gtest-1.7.0/libgtest.a

工作順序：

g++ -L../sdl-frame/sdl_frame/bin/Debug -L/home/yeti/Programs/gtest-1.7.0 -o bin/Debug/sdl_frame_sample obj/Debug/main.o obj/Debug/src/sample_game_t.o obj/Debug/src/sample_world_t.o  ../../sdl-frame/sdl_frame/bin/Debug/libsdl_frame.a -lSDL2 -lSDL2main -lSDL2_ttf -lSDL2_image  /home/yeti/Programs/gtest-1.7.0/libgtest.a

現在在鏈接器設置中是這樣的：

希望有人會發現這很有用。 如果有人知道更好的修復方法，我將非常感興趣。