rust-objcopy is x86-64 executable on aarch64-unknown-linux-gnu

[Stevenjin8]

If I download https://static.rust-lang.org/dist/rust-1.85.1-aarch64-unknown-linux-gnu.tar.xz (link from https://forge.rust-lang.org/infra/other-installation-methods.html#standalone-installers), all the files are ARM executables except for ./rustc/lib/rustlib/aarch64-unknown-linux-gnu/bin/rust-objcopy which is an x86_64 executable.

$ file ./rustc/lib/rustlib/aarch64-unknown-linux-gnu/bin/rust-objcopy
./rustc/lib/rustlib/aarch64-unknown-linux-gnu/bin/rust-objcopy: ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=285124b3756870de665b8585d6c9cb3a72a13eca, for GNU/Linux 3.2.0, not stripped

I expected to see this happen to be a aarch executable

[Stevenjin8]

rust-lang/www.rust-lang.org#2127

[moxian]

@rustbot label: +T-bootstrap +O-aarch64

[Noratrieb]

the relevant logic is here:

rust/src/bootstrap/src/core/build_steps/compile.rs

Line 2193 in 068609c

debug!(

I don't see anything obvious standing out. note that rust-objcopy is only used for MacOS so this shouldn't cause problems in practice.

[Stevenjin8]

Yeah its not a big issue for me. I just came across this and figured I'd make an issue just in case. Thanks for taking the time to look into this!

[alex-berger]

I don't see anything obvious standing out. note that rust-objcopy is only used for MacOS so this shouldn't cause problems in practice.

@Noratrieb Actually, it causes problems in practice. For example in our use case where we are cross-compiling from Linux to macOS.

ab566a1583b4:/workdir# uname -m
aarch64
ab566a1583b4:/workdir# file /root/.rustup/toolchains/stable-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/bin/rust-objcopy
/root/.rustup/toolchains/stable-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/bin/rust-objcopy: ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=314f8cd18e99dc0dd8d0f1cd88dd44291cb566c0, for GNU/Linux 3.2.0, not stripped

Which then leads to build failures/errors like this:

error: unable to run `rust-objcopy`: Exec format error (os error 8)

[tindzk]

I encountered the same issue as @alex-berger when cross-compiling to macOS. This can be used as a workaround on Alpine Linux:

apk add llvm
binary=/usr/local/rustup/toolchains/1.86.0-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/bin/rust-objcopy
rm $binary
ln -s /usr/bin/llvm-objcopy $binary