Hello again, I've refreshed the branch again, and now there are no performance problems with the cross-built rustc.
But Ludovic mentioned that the binary would need to be statically linked rather than dynamically linked, and in the case of rustc that complicates things because it relies on dynamic linkage for its procedural macros, a feature it uses and thus requires to build itself. It could perhaps work to 'guix pack' it into a relocatable pack, but that'd be fragile and not very clean, compared to a statically link archive. The road ahead is 1. Try to 'cargo expand' the crates that use other proc macros crates, and de-register the proc-macros crates from the rust sources. Rust bundles about 40 proc-macros crates. That's not guaranteed to work easily, unfortunately, as 'cargo expand' is a lossy process and not guaranteed to be correct. 2. Supposing 1 works, it should be possible to build a statically linked rust/cargo. If the above fail or is too difficult to achieve, we could explore a 'guix pack'-based solution. Thanks, Maxim
