[PSA] Public Service Announcements Thread

[bjorn3]

This issue will be used to communicate changes to the way cg_clif is built or used as well as to notify about the implementation of major features.

[bjorn3]

I will lock this issue to prevent noise.

[bjorn3]

In about 24h from now I will be merging https://github.com/bjorn3/rustc_codegen_cranelift/pull/1300, which renames the build/ directory to dist/. This means you will have to use dist/cargo-clif instead of build/cargo-clif.

[bjorn3]

https://github.com/bjorn3/rustc_codegen_cranelift/pull/1347 will drop the precompiled CI artifacts for cross compiling from x86_64 Linux to AArch64 and S390x Linux to reduce the negative effects on CI time this PR has. Cross compile artifacts for x86_64 Linux to x86_64 MinGW Windows will remain and so will all non-cross-compilation artifacts. If you want to cross-compile for one of the dropped targets you will need to build cg_clif yourself.

[bjorn3]

As of https://github.com/bjorn3/rustc_codegen_cranelift/pull/1365 the latest CI artifacts will now be published as release at https://github.com/bjorn3/rustc_codegen_cranelift/releases/tag/dev.

[bjorn3]

I just noticed a huge runtime perf improvement for the simple-raytracer benchmark caused by the update from nightly-2023-10-09 to nightly-2023-10-19. (links are to the benchmark results) Compilation time improved for both the LLVM and Cranelift backend, but relatively speaking the improvement was bigger for the Cranelift backend. I am fairly certain this improvement comes from rust-lang/rust#116505, which enables the MIR inliner to inline small functions cross-crate even if they lack #[inline].

[bjorn3]

macOS builds were silently broken for about two weeks as github switched the architecture of the macOS CI runners from x86_64 to arm64, causing us to build arm64 binaries. These binaries were broken as arm64 macOS is currently not supported: #1248 I've pushed a fix to force building x86_64 binaries again.

[bjorn3]

As of #1500 arm64 macOS (Apple Silicon) is now supported and pre-compiled builds are now available at https://github.com/bjorn3/rustc_codegen_cranelift/releases/tag/dev.

Edit: If you use XCode 15, make sure to use RUSTFLAGS="-Clink-arg=-ld_classic" as the new linker doesn't like our object files.
Edit2: Now works fine with XCode 15 as of 3d54358.

[bjorn3]

I'm planning to drop building the Linux to Windows cross-compilation toolchain in CI soon. It will remain possible to build a cross-compilation toolchain locally as well as (once all Windows ABI compat issues are fixed) to use the rustup distributed version of cg_clif to cross-compile.
Edit: Done in 113af15.