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CMake does not properly bind files after successful build

I have a simple project that I am trying to automate the build with cmake. Everything went fine until I ran into a brick wall with the cmake build process. I think it’s best if I show you the whole project.

project/
    CMakeLists.txt **[1]**
    build/
    source/
        CMakeLists.txt **[2]**
        main.c
        game/
        CMakeLists.txt **[3]**
        game.c
        game.h

main.c

#include <stdio.h>
#include "game/game.h"

int main(int argc, char const *argv[]) {

  initSdlAccel(480, 320, "this is a test");

  return 0;
}

game.h

#include <stdlib.h>
#include <string.h>
#include <SDL.h>
#include <SDL_image.h>
#include <SDL_ttf.h>
#include <SDL_mixer.h>

void initSdlAccel(int width, int height, const char *title);

game.c

#include "game.h"

SDL_Window *window;
SDL_Renderer *renderer;

void initSdlAccel(int width, int height, const char *title)
{
  if (SDL_Init(SDL_INIT_EVERYTHING) != 0)
  {
    SDL_Log("sdl failed to init");
    SDL_Quit();
  }

  window = SDL_CreateWindow(title, 100, 100, width, height, SDL_WINDOW_SHOWN);
  if(window == NULL)
  {
    SDL_Log("sdl failed to create window");
    SDL_Quit();
  }

  renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
  if(window == NULL)
  {
    SDL_Log("sdl failed to create renderer");
    SDL_Quit();
  }
}

CMakeLists.txt [1]

CMAKE_MINIMUM_REQUIRED(VERSION 2.8)

PROJECT(game)

set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)

IF(APPLE)
   #SET(GUI_TYPE MACOSX_BUNDLE)
   SET(INCLUDE_DIRS /Library/Frameworks/SDL2.framework/Headers
                    /Library/Frameworks/SDL2_ttf.framework/Headers
                    /Library/Frameworks/SDL2_mixer.framework/Headers
                    /Library/Frameworks/SDL2_image.framework/Headers)
   INCLUDE_DIRECTORIES ( "${INCLUDE_DIRS}" )
   FIND_LIBRARY(SDL2_LIBRARY Sdl2)

   SET(EXTRA_LIBS ${Sdl2} )
   INCLUDE_DIRECTORIES("${INCLUDE_DIRS}")
ENDIF (APPLE)

ADD_SUBDIRECTORY(source)
ADD_SUBDIRECTORY(source/game)

CMakeLists.txt [2]

PROJECT(launcher)

SET(SRC_FILES main.c)

INCLUDE_DIRECTORIES("${PROJECT_BINARY_DIR}")

ADD_EXECUTABLE(launcher "${SRC_FILES}")
TARGET_LINK_LIBRARIES(launcher game)

CMakeLists.txt [3]

PROJECT(game)

SET(SRC_FILES game.c)

ADD_LIBRARY(game "${SRC_FILES}")
#
Undefined symbols for architecture x86_64:
  "_SDL_Log", referenced from:
      _initSdlAccel in libgame.a(game.c.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [bin/launcher] Error 1
make[1]: *** [source/CMakeFiles/launcher.dir/all] Error 2
make: *** [all] Error 2

This is pretty simple, or at least it should be a pretty simple installation setup, but I just can't get the game.c file to actually use the included SDL files. They were found correctly, because if I delete the specific Apple code from the main CMakeLists file, it will not even be created.

How can I sort this?

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3 answers

CMakeLists.txt [3] :

TARGET_LINK_LIBRARIES(game ${SDL2_LIBRARY})

${SDL2_LIBRARY} TARGET_LINK_LIBRARIES, CMakeLists.txt [2]...

+5

SDL, . Find* - , include library.

, SDL, Find_Library.

, , FindSDL, , .

+3

To reinforce the previous answer, EXTRA_LIBS is set, but never mentioned. This is not a magic variable, you should use it.

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