MacOS: Undefined symbols for architecture x86_64

[PsiACE]

   = note: Undefined symbols for architecture x86_64:
            "_preadv", referenced from:
                nix::sys::uio::preadv::h8c66d9fb8b619a73 in libnix-1b7d7137231b30ff.rlib(nix-1b7d7137231b30ff.nix.1b5c8824-cgu.0.rcgu.o)
            "_pwritev", referenced from:
                nix::sys::uio::pwritev::hb39f620af1eb34cc in libnix-1b7d7137231b30ff.rlib(nix-1b7d7137231b30ff.nix.1b5c8824-cgu.0.rcgu.o)
          ld: symbol(s) not found for architecture x86_64
          clang: error: linker command failed with exit code 1 (use -v to see invocation)

[asomers]

What command results in that error? What version of OSX are you using? And, if you know, why doesn't this happen in CI?

[PsiACE]

What command results in that error?

      - name: Run test
        uses: actions-rs/cargo@v1
        with:
          command: test
          components: rustfmt
          args: --all-features --no-fail-fast
        env:
          RUST_TEST_THREADS: 2
          RUST_LOG: debug
          RUST_BACKTRACE: full
          CARGO_INCREMENTAL: '0'
          RUSTFLAGS: '-Zprofile -Ccodegen-units=1 -Cinline-threshold=0 -Clink-dead-code -Coverflow-checks=off -Zpanic_abort_tests'
          RUSTDOCFLAGS: '-Zprofile -Ccodegen-units=1 -Cinline-threshold=0 -Clink-dead-code -Coverflow-checks=off -Zpanic_abort_tests'

What version of OSX are you using?

macos-latest

And, if you know, why doesn't this happen in CI?

This happen in CI.

[asomers]

I meant Nix's CI, not yours. Nix's CI does not fail with this error. Can you determine what is different about Nix's CI environment and yours? You have a lot of stuff in RUSTFLAGS there. Maybe one of those is responsible? Is there anything unusual about the toolchain you're using? And what command causes the error? What you pasted above is not a command, it's a github actions definition. I need to know exactly what command is failing.

[PsiACE]

Looks like #1590 fixes the issue, I'll check it out.

Can you determine what is different about Nix's CI environment and yours?

I can't.

Maybe one of those is responsible?

I don't have a macos environment, but all this will not fail under linux.

Is there anything unusual about the toolchain you're using?

nightly-2021-09-11 with pprof, our project is https://github.com/datafuselabs/databend

And what command causes the error?

cargo test --all-features --no-fail-fast

[asomers]

What version of OSX are you using? I can reproduce your problem on Catalina, but not Monterey or Big Sur. I don't know what you mean by "latest".

[rivy]

For the Github Actions CI, 'macos-latest' is currently OSX v10.15 (or "Catalina" in your parlance).

[asomers]

In that case the problem is either that one of your dependencies is actually trying to use preadv/pwritev, or it's the -Clink-dead-code. Normally unlinkable symbols shouldn't be a problem if they aren't actually used.

[rivy]

It would have to be the -Clink-dead-code option as the code compiles and tests normally until testing code coverage (for our repo, 'uutils/coreutils'). Unfortunately, the -Clink-dead-code is required for code coverage by grcov.

Hmm... could it be feature-gated? Or, I guess, feature-blocked?