Issue #21929 has been updated by alanwu (Alan Wu). Status changed from Open to Feedback It's hard for me to tell what's desired beyond the already merged PR you proposed. It seems to be about some mechanism for flag overriding for development builds that use `cargo`, but sort of by default definition packaging is not a great fit for development because the code is changing all the time. A debug build that uses only rustc is already possible using the mechanism in the merged PR. ---------------------------------------- Feature #21929: Add configure script options for instrumenting Rust builds https://bugs.ruby-lang.org/issues/21929#change-116723 * Author: jprokop (Jarek Prokop) * Status: Feedback ---------------------------------------- Ruby at this moment optionally includes Rust bits. Right now this touches mostly YJIT and ZJIT. Rust is a compiled language with various compile flags at various stages and approaches. My ask is to provide a way to instrument compilation similarly as with C at the moment so that packagers and distributions can be fully and easily compliant with their guidelines on compilation flags. Currently, for production build of Ruby, `rustc` tool is used, which is instrumented differently from `cargo` in debug builds. In my PR motivated by the described goal: https://github.com/ruby/ruby/pull/15695 I have focused on providing `rustc` with our distribution flags, during the PR it was mentioned that there are flags related to security https://github.com/ruby/ruby/pull/15695#discussion_r2663651764 that should be present even when providing distribution flags. This is not too different from C, as there are also security flags, such as configure script enabling the arm64's BTI and PAC when possible. `rustc` of version 1.92, at the time of the PR uses the last mention of a flag. Ideally `rustc` would know `RUSTFLAGS`, but as far as I can tell, the enviroment variable only affects `cargo`. In Fedora the current guidance recommends using `%build_rustflags` https://docs.fedoraproject.org/en-US/packaging-guidelines/Rust/#_compiler_fl... which expands to `-Copt-level=3 -Cdebuginfo=2 -Ccodegen-units=1 -Cstrip=none -Cforce-frame-pointers=yes --cap-lints=warn` The best result is each part of Rust in Ruby would receive the flags defined during `configure` time. In cases where complication flags should conflict, in Fedora distribution flags take precedence: https://docs.fedoraproject.org/en-US/packaging-guidelines/Rust/#_building_wi... -- https://bugs.ruby-lang.org/