Stream: t-compiler/major changes

Topic: rebuild rustc with existing libstd/libcore


bjorn3 (Jul 18 2020 at 12:06, on Zulip):

eddyb said:

maybe bjorn3 has good news regarding the cranelift backend, i.e. maybe it's less hopeless than LLVM

Compile time is better, but runtime is slightly worse than even LLVM debug mode. Rustc is normally always built with optimizations, as it can then compile later stages much (up to 10x) faster.

lqd (Jul 18 2020 at 12:11, on Zulip):

is peepmatic the "only" / most prominent work for cranelift optimisations ? (and btw do we have results about the approach already ?) (the move into wasmtime has made keeping up to date with cranelift as a whole a bit tough :)

eddyb (Jul 18 2020 at 12:12, on Zulip):

@bjorn3 alright, thanks for the clarification!

Joshua Nelson (Jul 18 2020 at 12:46, on Zulip):

I'm interested in both "build libstd/libcore, but only once, not every time I change anything in rustc" and "don't build libstd/libcore at all, just use the one from the rustup nightly".

@comex this is build --stage 1 src/libstd --keep-stage 1. But I've heard it might break things in the standard library.

Joshua Nelson (Jul 18 2020 at 12:48, on Zulip):

Oh whoops eddyb already mentioned that

Notification Bot (Jul 18 2020 at 13:35, on Zulip):

This topic was moved by simulacrum to #t-compiler > rebuild rustc with existing libstd/libcore

Last update: May 07 2021 at 06:15UTC