cargo-clippy | cargo clippy | DevOps library

So, here is the summary of our investigations.

The base image used for build is i386/ubuntu with 32-bit environment inside, however, this image does nothing to appropriately mask the results of uname(2) calls (by having something like setarch linux32 as entrypoint), so, when running on 64-bit system (your case), any process inside the build container calling uname(2) or uname(1) sees x86_64 instead of i686. This is the root of the problem.

When you install cargo, you download and run the installation script, which detects the platform it runs on and downloads the appropriate version of rustup-init. The platform detection in this script recognizes correctly that it runs in 32-bit environment but on 64-bit kernel, so the script downloads 32-bit version of rustup-init. However, rustup-init decides that it runs on x86_64 (probably it sees x86_64 returned by uname(2), but does not perform the check for "32-bit environment on 64-bit kernel" case, like the installer script does). You can see it during the installation without -y: