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c++c++11allegroallegro5

How to link allegro5 library to C++ project

I have got a C++ project written in CodeBlocks but I do not know how to link it with allegro5. I want to make people able to compile my project without installing any libraries or packages. So I put allegro directory downloaded from their webpage into project folder. Next I included library

    #include "allegro/include/allegro5/allegro5.h"

But when I try to compile I have got an error

/home/stanek/ClionProjects/proj/guiMain.cpp:17: undefined reference to `al_install_system'
/home/stanek/ClionProjects/proj/guiMain.cpp:22: undefined reference to `al_create_display'
/home/stanek/ClionProjects/proj/guiMain.cpp:28: undefined reference to `al_map_rgb'
/home/stanek/ClionProjects/proj/guiMain.cpp:28: undefined reference to `al_clear_to_color'
/home/stanek/ClionProjects/proj/guiMain.cpp:30: undefined reference to `al_flip_display'
/home/stanek/ClionProjects/proj/guiMain.cpp:32: undefined reference to `al_rest'
/home/stanek/ClionProjects/proj/guiMain.cpp:34: undefined reference to `al_destroy_display'

This is my guiMain.cpp:

#include <iostream>
#include "allegro/include/allegro5/allegro5.h"


using namespace std;

int main(int argc, char **argv){

    ALLEGRO_DISPLAY *display = NULL;

    if(!al_init()) {
        fprintf(stderr, "failed to initialize allegro!\n");
        return -1;
    }

    display = al_create_display(640, 480);
    if(!display) {
        fprintf(stderr, "failed to create display!\n");
        return -1;
    }

    al_clear_to_color(al_map_rgb(0,0,0));

    al_flip_display();

    al_rest(10.0);

    al_destroy_display(display);

    return 0;
}

And this is my CMakeList.txt

cmake_minimum_required(VERSION 3.3)
project(proj)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -Wall -std=c++11")

set(SOURCE_FILES guiMain.cpp)
add_executable(projids ${SOURCE_FILES})

UPDATE: I have changed set in my CMakeList

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -Wall -std=c++11 'pkg-config --cflags --libs allegro-5.0 '")

but I have got an error:

    Error:Configuration proj [Debug]
Compiler exited with error code 1: /usr/bin/c++ -xc++ -g -Wall -std=c++11 'pkg-config --cflags --libs allegro-5.0 ' -g -v -dD -E
c++: error: pkg-config --cflags --libs allegro-5.0 : No such file or directory
Using built-in specs.
COLLECT_GCC=/usr/bin/c++
Target: x86_64-unknown-linux-gnu
Configured with: /build/gcc/src/gcc-5-20160209/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared --enable-threads=posix --enable-libmpx --with-system-zlib --with-isl --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --disable-multilib --disable-werror --enable-checking=release
Thread model: posix
gcc version 5.3.0 (GCC)

and 

Error:Configuration proj [Release]
Compiler exited with error code 1: /usr/bin/c++ -xc++ -g -Wall -std=c++11 'pkg-config --cflags --libs allegro-5.0 ' -O3 -DNDEBUG -v -dD -E
c++: error: pkg-config --cflags --libs allegro-5.0 : No such file or directory
Using built-in specs.
COLLECT_GCC=/usr/bin/c++
Target: x86_64-unknown-linux-gnu
Configured with: /build/gcc/src/gcc-5-20160209/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared --enable-threads=posix --enable-libmpx --with-system-zlib --with-isl --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --disable-multilib --disable-werror --enable-checking=release
Thread model: posix
gcc version 5.3.0 (GCC)
Solution

  • Actually, it is possible to allow others to play your game without intalling the allegro libraries on their system.

    One approach is to statically link your executable to static versions of the allegro libraries. The allegro wiki actually has a tutorial on how to do this with Code::Blocks.

    In short, static linkage includes the necessary parts of Allegro directly in your executable so the user doesn't have to worry about linking when they run it.

    Another option is to use dynamic linkage, but package the needed dynamic libraries along with your game. For example, your game folder might look like:

    bin/
    my_game.exe
    liballegro.dll
    liballegro_color.dll
    ...

    Then the user can link to the libraries you have provided without worrying about what is installed on their system.

    Note that dynamic libraries typically end with .so (Linux) or .dll (Windows) while static libraries end with .a.

    Edit:

    Just read you said compile and not run. If you want them to compile it themselves, you will need to include the libraries or instruct them on how to get the libraries themselves.