Use crosstool-ng for dist-arm-linux-musl

[Gelbpunkt]

Almost all of the musl dist jobs use crosstool-ng, only the aarch64 and x86_64 jobs use musl-cross-make. Let's start transitioning the remaining jobs over to crosstool-ng and start dropping musl-cross-make.

I noticed that this job is called dist-arm-linux-musl, but the GNU pendant is called dist-aarch64-linux. How would I go about renaming dist-arm-linux-musl to dist-aarch64-linux-musl? Is there any external effort required or can I just rename it in the repo?

try-job: dist-arm-linux-musl

[rustbot]

r? @marcoieni

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[marcoieni]

I think you can just rename it (together with the corresponding docker image). You can do it in another PR, too.

FYI rust-lang/infra-team#190

I'm reviewing the PR 👀

[marcoieni]

should we explain why this is not set? 🤔

[marcoieni]

why we increased this version?

[Gelbpunkt]

This crosstool-ng config was unused before and for ARMv7. The musl-cross-make toolchain used before had 4.19 headers

[Gelbpunkt]

And no, I don't know why it was here or why it was for a 32-bit glibc toolchain :) Some of these dist jobs are a mess, which is why I'm trying to clean them up a bit

[marcoieni]

@bors try

[bors]

⌛ Trying commit a4813e0 with merge 3a16f98...

[bors]

☀️ Try build successful - checks-actions
Build commit: 3a16f98 (3a16f9895e7524cede8ae9b28d03a2563348525d)

[marcoieni]

I downloaded the try build artifacts and compared them with the auto build artifacts from the last commit on master.

rustc-nightly-aarch64-unknown-linux-musl/rustc/bin/rustc is 71KB here, while in the latest autobuild is 11KB.

Is this size increase expected?

[Gelbpunkt]

Seems a bit weird. I downloaded them and at first glance, only the rustc binary is a tiny bit larger indeed.

autobuild:

ELF 64-bit LSB pie executable, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-musl-aarch64.so.1, with debug_info, not stripped

try-build:

ELF 64-bit LSB pie executable, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-musl-aarch64.so.1, not stripped

llvm-readelf also confirms that the debuginfo sections are missing in the new one. Not sure why that'd increase the binary size though, I'll investigate a bit more.

I have a feeling that this is related to the changed CFLAGS.