jlskuz / linuxdeploy-plugin-checkrt

Have your AppImage check libgcc and libstdc++ dependencies at runtime.

linuxdeploy-plugin-checkrt

This linuxdeploy plugin allows you to deploy libstdc++.so.6 and libgcc_s.so.1 without breaking compatibility. The installed AppRun hook script will compare the symbol version numbers between the deployed libraries and those on your system and only add the deployed ones to LD_LIBRARY_PATH if they're newer.

Additionally the library exec.so is deployed and will be preloaded by AppRun if it's found. This library is intended to restore the environment of the AppImage's parent process in order to avoid library clashing of bundled libraries with external processes called from within the AppImage (i.e. when a webbrowser is opened or a terminal emulator is started). If you don't want exec.so then simply delete it before creating your final AppImage.

Requirements

C compiler (GCC or Clang)

Usage

# get linuxdeploy and linuxdeploy-plugin-checkrt and make them executable
wget -c "https://github.com/darealshinji/linuxdeploy-plugin-checkrt/releases/download/continuous/linuxdeploy-plugin-checkrt.sh"
wget -c "https://github.com/linuxdeploy/linuxdeploy/releases/download/continuous/linuxdeploy-x86_64.AppImage"
chmod a+x linuxdeploy-x86_64.AppImage linuxdeploy-plugin-checkrt.sh

# add GCC's libraries to the search path
# and call through linuxdeploy using the `--plugin checkrt` option
LD_LIBRARY_PATH="/path/to/my/gcc-snapshot/lib64" \
  ./linuxdeploy-x86_64.AppImage --appdir AppDir --plugin checkrt --output appimage --icon-file mypackage.png --desktop-file mypackage.desktop

Why?

libstdc++.so.6 and libgcc_s.so.1 are part of GCC and if you compile code it will be linked against these libraries if required. If you use a newer version of GCC than normally available on your system these libraries will also be newer and chances are high that your program - linked against these newer versions - is no longer compatible to those installed by default on your system.

Starting your program would get you an error message like this:

./myApp: /lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.29' not found (required by ./myApp)

However you cannot simply bundle these libraries as usual. If the AppImage is started on a different system and an unbundled system library depends on a newer version than available from the AppImage it won't work either.

This linuxdeploy plugin will install a hook script that quickly checks and compares the internal version number of the libraries and only adds them to the search path if they're newer.

Hacking

The file linuxdeploy-plugin-checkrt.sh is created from generate.sh. To add changes to the plugin you must edit the other files and then run ./generate.sh.