I have built the rust-polling successfully in my local loong64 environment, without modifications required.
Make sure you are not using DEB_BUILD_OPTIONS=nocheck
since rust crates don't have stable ABIs and cargo doesn't support pre-built rust crates, librust* packages contain source code rather than binaries of any sort. The package build process does a test build to check that the code is actually buildable before packaging but this is skipped if DEB_BUILD_OPTIONS=nocheck is set.
Please try to rebuild rust-polling for loong64 in the Debian Package Auto-Building environment.
It failed again. I've taken a quick look at the code, but I'm not seeing anything obvious. The definitions in linux-raw-sys seem to exist, at least accoding to the error messages. I notice that the reexports of those definitions are gaurded behind a target_pointer_bits guard, it may be worth checking if rustc is setting that correctly on your architecture (though if it isn't, I'd expect that to cause a lot of problems)
