[thagsimmons]

This is absolutely a pain point for us, working on a very large Rust project. In particular, incremental compile times are absolutely critical for developer comfort, and by far the most common complaint working on our codebase is that developer tooling, IDEs and running unit tests is slow. We've done everything that can reasonably be done - splitting the project into crates, using mold as a linker (the single biggest improvement), etc. Without a really big improvement to incremental compile, we will have a continuing drag on our development momentum.

[eminence32]

I'm curious what are your actual compile times? What does "painfully long" mean for you and your workflow? 15 seconds? 2 minutes? 15 minutes?

[thagsimmons]

This is a bit of a "how long is a piece of string" question. It depends on the developer workstation, which file they're currently working on, etc. That said, we're talking about incremental compile times here, not total project from-scratch compile times. A lag of a few seconds really makes a difference to developer comfort - I'd say, when it's an issue, we're talking about rust-analyzer responsiveness (mainly due to cargo check on save, which can be disabled) of a 3-8 seconds, and delays in running unit tests of 5-20 seconds. I work on a super beefy ThreadRipper monster so I'm less affected, but colleagues on under-powered laptops suffer a lot.

[Alifatisk]

Painfully long to me is everything over 5 seconds.

[leeoniya]

maybe https://github.com/bjorn3/rustc_codegen_cranelift

https://old.reddit.com/r/rust/comments/107afei/cranelift_mol...