Plugin linking order causes errors with clang

[martonperei]

I'm using clang version 3.4-1ubuntu3 and I'm getting undefined references when linking plugins. If i reorder the linked libraries so plugins are listed first, everything works fine. Clang does not seem to support --start-group and --end-group.

We could pass the plugins in the minko.project.application call and enable them before linking the minko framework:

minko.project.application("minko-tutorial-" .. PROJECT_NAME, {"sdl", "lua"})

and

minko.project.application = function(name, plugins)

    minko.project.library(name)

    kind "WindowedApp"

    if plugins ~= nil then
        for _, plugin in pairs(plugins) do
            minko.plugin.enable(plugin)
        end
    end

...

The error:

Linking minko-tutorial-12-working-with-normal-maps
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::Canvas::initializeContext(std::string const&, unsigned int, unsigned int, bool)':
src/minko/Canvas.cpp:(.text+0xc9c): undefined reference to `minko::render::OpenGLES2Context::OpenGLES2Context()'
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::Canvas::initializeInputs()':
src/minko/Canvas.cpp:(.text+0x1181): undefined reference to `minko::input::Keyboard::Keyboard()'
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::Canvas::step()':
src/minko/Canvas.cpp:(.text+0x4c37): undefined reference to `minko::async::Worker::update()'
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::Canvas::SDLKeyboard::SDLKeyboard()':
src/minko/Canvas.cpp:(.text+0x5658): undefined reference to `minko::input::Keyboard::Keyboard()'
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::async::FileLoaderWorker::FileLoaderWorker()':
src/minko/Canvas.cpp:(.text._ZN5minko5async16FileLoaderWorkerC2Ev[_ZN5minko5async16FileLoaderWorkerC2Ev]+0x24): undefined reference to `minko::async::Worker::Worker(std::string const&)'
src/minko/Canvas.cpp:(.text._ZN5minko5async16FileLoaderWorkerC2Ev[_ZN5minko5async16FileLoaderWorkerC2Ev]+0x3e): undefined reference to `vtable for minko::async::FileLoaderWorker'
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::Canvas::SDLJoystick::SDLJoystick(std::shared_ptr<minko::Canvas>, int, _SDL_Joystick*)':
src/minko/Canvas.cpp:(.text._ZN5minko6Canvas11SDLJoystickC2ESt10shared_ptrIS0_EiP13_SDL_Joystick[_ZN5minko6Canvas11SDLJoystickC2ESt10shared_ptrIS0_EiP13_SDL_Joystick]+0x51): undefined reference to `minko::input::Joystick::Joystick(std::shared_ptr<minko::AbstractCanvas>, int)'
../../plugin/sdl/bin/linux64/release/libminko-plugin-sdl.a(Canvas.o): In function `minko::Canvas::SDLMouse::SDLMouse(std::shared_ptr<minko::Canvas>)':
src/minko/Canvas.cpp:(.text._ZN5minko6Canvas8SDLMouseC2ESt10shared_ptrIS0_E[_ZN5minko6Canvas8SDLMouseC2ESt10shared_ptrIS0_E]+0x44): undefined reference to `minko::input::Mouse::Mouse(std::shared_ptr<minko::AbstractCanvas>)'
clang: error: linker command failed with exit code 1 (use -v to see invocation)

[warrenseine]

We've encountered this issue with Emscripten (based on Clang), which is why we have this terrible workaround (passing libraries twice).

Your solution works in some places, but not everywhere, as some projects enable libraries dynamically based on context.

Making a wrapper around Clang injecting libraries twice should be the (ugly) way to go.

[martonperei]

Thanks! Seems to work fine.