Passing quote escaped options to rustc doesn't work

[mvtec-bergdolll]

Problem

I'm trying to build a project with mcount instrumentation, however due to rust-lang/rust#92109 I have to specify a custom set of passes. I tried RUSTFLAGS="-Z instrument-mcount -C passes=\"ee-instrument post-inline-ee-instrument\"" cargo +nightly build --release and RUSTFLAGS="-Z instrument-mcount -C passes=ee-instrument post-inline-ee-instrument" cargo +nightly build --release and some other combinations and I always get errors that look something like this:

process didn't exit successfully: rustc - --crate-name ___ --print=file-names -Z instrument-mcount -C 'passes="ee-instrument' 'post-inline-ee-instrument"' --crate-type bin --crate-type rlib --crate-type dylib --crate-type cdylib --crate-type staticlib --crate-type proc-macro --print=sysroot --print=cfg (exit status: 1)

To me it seems it doesn't forward the escaped string in an intuitive way to rustc.

Steps

1. Build project with RUSTFLAGS="-Z instrument-mcount -C passes=\"ee-instrument post-inline-ee-instrument\"" cargo +nightly build --release
2. Error

Possible Solution(s)

No response

Notes

Happens on Linux with zsh and bash.

Version

cargo 1.67.0-nightly (9286a1beb 2022-11-04)

[ehuss]

Indeed RUSTFLAGS does not support spaces. I think it is unlikely we will add any sort of shell-parsing for that. There are some alternatives now:

• use CARGO_ENCODED_RUSTFLAGS which allows spaces
• use --config 'build.rustflags=["arg1", "arg2"]'
• Set build.rustflags in config.toml

I'm going to close as a duplicate of #3686.

[mvtec-bergdolll]

@ehuss could you please give an example how to achieve the cargo equivalent rustc -C passes="ee-instrument post-inline-ee-instrument" .... I failed to achieve this with any of your provided alternatives. Note that some versions such as --config 'build.rustflags=["-C", "passes=ee-instrument post-inline-ee-instrument"]' build but don't actually achieve the desired effect, as checked with nm <binary> | rg mcount

[ehuss]

If you are using a bash-like shell, something like this should work:

CARGO_ENCODED_RUSTFLAGS=$'-Zinstrument-mcount\u001f-Cpasses=ee-instrument aa-eval' cargo b -v

With -v you should be able to inspect that flags being passed to rustc. If your desired passes/instrumentation aren't showing up, I would suspect its an issue with rustc or the passes being used.