Make appimagetool run on Alpine/musl about go-appimage

[probonopd]

So appimagetool itself is running on musl based systems like Alpine, and the resulting AppImages (that bundle everything) can run on glibc-based systems.

We are now blocked by AppImage/AppImageKit#1015.

[probonopd]

@s-zeid just confirmed that the appimagetool AppImage using the experimental static AppImage runtime works on Alpine Linux.

But appimaged is dynamically linked. Why? Can we make it static?

[probonopd]

Well, appimagetool runs on Alpine but not in -s deploy mode yet, because it assumes to be working on glibc. For musl, it's probably a matter of leaving a few things away?

VERSION=1 ./appimagetool-730-x86_64.AppImage -s deploy ./xterm.AppDir/usr/share/applications/
xterm.desktop 
AppDir path: xterm.AppDir
Exec= key contains: xterm
Icon= key contains: xterm-color_48x48
2022/11/06 20:14:46 Gathering all required libraries for the AppDir...
2022/11/06 20:14:46 len(allELFsUnderPath): 1
2022/11/06 20:14:46 libraryLocations: [xterm.AppDir/usr/bin /usr/lib64 /lib64 /usr/lib /lib /usr/lib/x86_64-linux-gnu/libfakeroot /usr/local/lib /usr/local/lib/x86_64-linux-gnu /lib/x86_64-linux-gnu /usr/lib/x86_64-linux-gnu /lib32 /usr/lib32]
2022/11/06 20:14:46 len(allELFs): 25
2022/11/06 20:14:46 Deploying /lib/ld-musl-x86_64.so.1...
2022/11/06 20:14:46 Patching ld-linux...
2022/11/06 20:14:46 Determining gconv (for GCONV_PATH)...
ERROR Could not deploy the interpreter: did not find gconv
/ # 

[probonopd]

Disabled the fatal error on that check for now, and as a result I am able to deploy applications from Alpine Linux with ``-s deploy`.

Hence closing. Further improvements can be addressed in separate tickets.

References:

• dosemu2/dosemu2#2133
• https://github.com/probonopd/doesemu2-factory/blob/c34ada32831f8f5ff6acfab87b4821825d58f99b/build.sh