How to compile native C++ using MinGW in/target Windows?

sent44

I want to test compile before I do actual coding and it is fail for me. Example SConstruct and Github readme only mention LLMV for Windows, not MinGW. Here is what I do

gcc -m64 -fPIC -g -c -I"../godot-cpp/godot_headers/" -I"../godot-cpp/include/" -I"../godot-cpp/include/core/" -I"../godot-cpp/include/gen/" Map.cpp -o Map.o
gcc -m64 -fPIC -g -c -I"../godot-cpp/godot_headers/" -I"../godot-cpp/include/" -I"../godot-cpp/include/core/" -I"../godot-cpp/include/gen/" Map/Generator.cpp -o Generator.o

compile is pass but when I link with

gcc -m64 --shared -L"../godot-cpp/bin" -l"godot-cpp.windows.debug.64" Map.o Generator.o -o map.dll

link fail with multiply undefined reference

! I use TMD-GCC 64 to target 64 bits platform ! ! Project Structure ! root ! --- game ! ------ (whatever) ! --- godot-cpp ! ------ (whatever) ! --- src (working dir) ! ------ Map ! --------- Generator.cpp ! --------- Generator.hpp ! ------ Map.cpp ! ! Code ! Map.cpp ! cpp ! #include <Godot.hpp> ! #include "Map/Generator.hpp" ! ! extern "C" void GDN_EXPORT godot_gdnative_init(godot_gdnative_init_options *o) { ! godot::Godot::gdnative_init(o); ! } ! ! extern "C" void GDN_EXPORT godot_gdnative_terminate(godot_gdnative_terminate_options *o) { ! godot::Godot::gdnative_terminate(o); ! } ! ! extern "C" void GDN_EXPORT godot_nativescript_init(void *handle) { ! godot::Godot::nativescript_init(handle); ! ! godot::register_class<Map::Generator>(); ! } ! ! Map/Generator.cpp ! cpp ! #include "Generator.hpp" ! ! Map/Generator.hpp ! hpp ! #pragma once ! #include <Godot.hpp> ! #include <Node.hpp> ! ! namespace Map{ ! class Generator : public godot::Node{ ! GODOT_CLASS(Generator, godot::Node); ! ! private: ! ! public: ! int test = 3; ! ! public: ! Generator(){} ! ~Generator(){} ! void _init(){} ! static void _register_methods(){ ! ! } ! }; ! } !

SIsilicon28

The godot cpp SConstruct has the following code at line 257.

elif env['platform'] == 'windows':
    if host_platform == 'windows' and not env['use_mingw']:
        # MSVC
        env.Append(LINKFLAGS=['/WX'])
        if env['target'] == 'debug':
            env.Append(CCFLAGS=['/Z7', '/Od', '/EHsc', '/D_DEBUG', '/MDd'])
        elif env['target'] == 'release':
            env.Append(CCFLAGS=['/O2', '/EHsc', '/DNDEBUG', '/MD'])

    elif host_platform == 'linux' or host_platform == 'osx':
        # Cross-compilation using MinGW
        if env['bits'] == '64':
            env['CXX'] = 'x86_64-w64-mingw32-g++'
            env['AR'] = "x86_64-w64-mingw32-ar"
            env['RANLIB'] = "x86_64-w64-mingw32-ranlib"
            env['LINK'] = "x86_64-w64-mingw32-g++"
        elif env['bits'] == '32':
            env['CXX'] = 'i686-w64-mingw32-g++'
            env['AR'] = "i686-w64-mingw32-ar"
            env['RANLIB'] = "i686-w64-mingw32-ranlib"
            env['LINK'] = "i686-w64-mingw32-g++"
    elif host_platform == 'windows' and env['use_mingw']:
        env = env.Clone(tools=['mingw'])
        env["SPAWN"] = mySpawn

    # Native or cross-compilation using MinGW
    if host_platform == 'linux' or host_platform == 'osx' or env['use_mingw']:
        # These options are for a release build even using target=debug
        env.Append(CCFLAGS=['-O3', '-std=c++14', '-Wwrite-strings'])
        env.Append(LINKFLAGS=[
            '--static',
            '-Wl,--no-undefined',
            '-static-libgcc',
            '-static-libstdc++',
        ])

If I'm not mistaken, this code gives a hint to how it compiles with Mingw, but it's setup for a building a static library, so a couple of adjustments will be necessary. It also might help to use Scons to build your library, but that's just a suggestion.

sent44

Oh, maybe -Wl,--no-undefined might work. I will try ASAP when I use computer. Thank you @SIsilicon28 . I almost give up on this.

sent44

I gave up. I tried to compile to Linux using WSL host and it was work! Using same WSL but target Windows, failed. Attempt to used MSVC, math.h was not found. Downloaded math.h from internet, other headers were not found instead. -Wl,--no-undefined is to force to error in case of undefined, which is still error so no effect.

sent44

I can now compile using MSVC (don't know if it is usable or not, don't have mood to do that now), still want to use MinGW more.