rust builds for qoriq do not work anymore

[hgy59]

Since some days the build of qoriq with (our own built) rust toolchain does not work anymore

There are errors like this:

2024-10-19T08:13:37.9481043Z    Compiling libc v0.2.161
2024-10-19T08:13:37.9481692Z    Compiling shlex v1.3.0
2024-10-19T08:13:37.9482436Z    Compiling proc-macro2 v1.0.88
2024-10-19T08:13:37.9496362Z    Compiling unicode-ident v1.0.13
2024-10-19T08:13:37.9650369Z error: the `-Z unstable-options` flag must also be passed to enable the flag `check-cfg`
2024-10-19T08:13:37.9651859Z error: the `-Z unstable-options` flag must also be passed to enable the flag `check-cfg`
2024-10-19T08:13:37.9653251Z error: the `-Z unstable-options` flag must also be passed to enable the flag `check-cfg`
2024-10-19T08:13:37.9654018Z 
2024-10-19T08:13:37.9654025Z 
2024-10-19T08:13:37.9655932Z 
2024-10-19T08:13:37.9662166Z error: the `-Z unstable-options` flag must also be passed to enable the flag `check-cfg`
2024-10-19T08:13:37.9663504Z 
2024-10-19T08:13:37.9672032Z error: could not compile `libc` (build script)
2024-10-19T08:13:37.9672877Z warning: build failed, waiting for other jobs to finish...
2024-10-19T08:13:37.9683523Z error: could not compile `proc-macro2` (build script)
2024-10-19T08:13:37.9685652Z error: could not compile `shlex` (lib)
2024-10-19T08:13:37.9687186Z error: could not compile `unicode-ident` (lib)
2024-10-19T08:13:37.9965512Z error: failed to compile `bat v0.24.0 (/github/workspace/spk/synocli-file/work-qoriq-6.2.4/bat-0.24.0)`, intermediate artifacts can be found at `/github/workspace/spk/synocli-file/work-qoriq-6.2.4/bat-0.24.0/target`.
2024-10-19T08:13:37.9967368Z To reuse those artifacts with a future compilation, set the environment variable `CARGO_TARGET_DIR` to that path.

[hgy59]

@th0ma7 is there any chance we get this fixed - or shall we drop all packages/tools depending on rust for qoriq models?

[hgy59]

This popped up in #6288 and #6007 (comment)

[th0ma7]

Well that's interesting... maybe a question of building an updated rust qoriq toolchain once again? Hopefuly the "howto" still is in our code in theory, but not ran since months.

I'll try to recall how to rebuild it, should be in theory relatively trivial... and probably a good time to further document as well. Let me see what I can do while I'm back home for the next few days.

[hgy59]

@th0ma7 do we still need #6137

[th0ma7]

I don't believe so, feel free to close.

[th0ma7]

So initiating a qoriq rust toolchain build is indeed quite simple: setting RUST_BUILD_TOOLCHAIN = 1 into spksrc.cross-rust-env.mk does all the magic!

But, as there needs to be a but... build fails at the end of the last stage, compiler error. I'll see if I'm able to build a specific version rather than latest stable and go from there (fingers crossed). But I fear we are, again, reaching the end of the line for qoriq ...

EDIT: this really revive bad memory / nightmares from trying to get a rust compiler for qoriq ... sigh.

[th0ma7]

@hgy59 ok, good news, got code locally that builds a 1.80.1 rust toolchain sucessfully and then builds bat with no errors as well... will upload that tomorrow.