Doesn't work on arm64 despite having package for it

[micr0-dev]

~ ❯ flatpak run com.github.Anuken.Mindustry
[E] arc.util.ArcRuntimeException: Couldn't load shared library 'libarcarm64.so' for target: Linux, 64-bit
	at arc.util.SharedLibraryLoader.load(SharedLibraryLoader.java:84)
	at arc.util.ArcNativesLoader.load(ArcNativesLoader.java:14)
	at arc.backend.sdl.SdlApplication.init(SdlApplication.java:107)
	at arc.backend.sdl.SdlApplication.<init>(SdlApplication.java:35)
	at mindustry.desktop.DesktopLauncher.main(DesktopLauncher.java:39)
Caused by: arc.util.ArcRuntimeException: Unable to read file for extraction: libarcarm64.so
	at arc.util.SharedLibraryLoader.readFile(SharedLibraryLoader.java:93)
	at arc.util.SharedLibraryLoader.loadFile(SharedLibraryLoader.java:253)
	at arc.util.SharedLibraryLoader.load(SharedLibraryLoader.java:81)
	... 4 more

OS: Fedora Linux Asahi Remix 40 (Workstation Edition) aarch64 
Host: Apple MacBook Air (13-inch, M2, 2022) 
Kernel: 6.8.10-400.asahi.fc40.aarch64+16k 

Packages: 2074 (rpm), 19 (flatpak) 
DE: GNOME 46.2 

Arm package should probably be removed until the project actually supports it

[TobTobXX]

Huh, I'm not too sure, but I thought it was java / libGDX and thus crossplatform. Is libGDX not on arm...?

[k8ieone]

It is unfortunate, but the developer is completely uninterested in bringing ARM support. There were a lot of issues open in the upstream repo about ARM support. All of them end like this one Anuken/Mindustry#4854

[k8ieone]

The game uses a game framework based on libGDX called arc. Anuken/Arc#167 This is the real blocker.

[TobTobXX]

Ok, thanks for collecting the links/infos. Submitted a PR to fix this. If aarch64 will be supported in the future, a new issue can be opened.

(btw, the issue may just go away if we can someday build it from source. It is not clear whether there are actual build issues when building for aarch64, there was an attempt, but I abandoned it because gradle is a PITA to generate flatpak modules from.)

[k8ieone]

Building from source is preferred for Flatpak afaik, but I get it. IIRC I tried building the game on bare metal on x86_64 at some point but eventually gave up as well.

[k8ieone]

I couldn't let this go so I tried getting an ARM build going today. My Arc fork with the necessary changes is here: https://github.com/k8ieone/Arc

I also found https://github.com/flatpak/flatpak-builder-tools/tree/master/gradle which means we should be able to build the Flatpak from source.

So far I was able to generate resources for both Arc and Mindustry. Unfortunately I wasn't able to generate it from the last release tag, only from the master branch. But at least it's a start. I'll try to move this along and modify the Flatpak manifest to build from source hopefully later this week.

You can find the generated resources in my fork: https://github.com/k8ieone/com.github.Anuken.Mindustry

Unfortunately I wasn't able to test the built jar file on my hardware. All my ARM systems run Alpine which is not supported so I won't be able to try this until I'm able to run it in Flatpak to avoid the musl incompatibility.

[TobTobXX]

Wow, nice job getting Arc to compile on aarch64 too! Did you get it to work outside of Flatpak? If yes, then it would be nice if you submitted the PR to Arc.

A few while ago I already tried building the Flatpak from source (#39). The gradle module from flatpak-builder-tools was still a PR then and I used a modified script instead (instead of parsing the gradle stdio output, I tried listing the gradle cache after a build). However Mindustry uses (used?) some weird dynamic dependency injection and the build tool didn't catch on. I'd recommend to not get your hopes high before you can test the flatpak.

[k8ieone]

Damn, thanks for letting me know. I'll still probably try it put while keeping in mind that it could end up not working.

About Arc, I did some more thinking on this and in its current state it needs to be built on ARM because I had issues getting SDL2 cross-compiled.

If we're able to solve this one little problem, I can see this getting accepted as a PR.

[TobTobXX]

I had issues getting SDL2 cross-compiled.

I've never not had isssues with cross-compiling :).

it needs to be built on ARM
[...]
If we're able to solve this one little problem, I can see this getting accepted as a PR.

Hmm... Well GitHub has ARM-runners, so the CI would (should) actually work if it works on your machine. Maybe try running the GitHub actions on your own account and check if the generated jar is working on arm. If this works, it is possible that the PR can still be accepted, even though x-compiling doesn't work.

[k8ieone]

Good point, I'll try that out.

[k8ieone]

@TobTobXX I managed to work around the SDL cross-compile by using an ARM Docker container for the SDL build. The rest of the libraries cross-compile nicely.

I left a comment in the Arc repo.

[k8ieone]

@TobTobXX Do you have a device that is a bit more modern where you could test it? The only device where I can easily try this is a Pinephone. I got GLXBadFBConfig which could be caused by the Pinephone's outdated hardware.

I had to set SDL_VIDEODRIVER=x11, otherwise I'd get Wayland unavailable.

GitHub didn't allow uploading it here, so here's a link to a file share.

https://cloud.mcld.eu/s/zwAgBwL7fEQjSAs

[k8ieone]

Alright, I did some more digging and found LIBGL_ALWAYS_SOFTWARE=true, using this I was able to force software rendering and it works! This leads me to believe that the issues I encountered above were indeed caused by ancient hardware.