420544a34a
rustc assumes that regular `extern "Rust"` functions unwind only if the `unwind` panic runtime is linked. `throw` was annotated as such, but unwound unconditionally. This could cause UB when a crate built with `-C panic=abort` called `throw` from `core` built with `-C panic=unwind`, since no terminator was added to handle the panic arising from calling an allegedly non-unwinding `extern "Rust"` function. rustc was taught to recognize this condition since https://github.com/rust-lang/rust/pull/144225 and prevented such linkage, but this caused regressions in https://github.com/rust-lang/rust/issues/148246, since this meant that Emscripten projects could not be built with `-C panic=abort` without recompiling std. The most straightforward solution would be to move `throw` into the `panic_unwind` crate, so that it's only compiled if the panic runtime is guaranteed to be `unwind`, but this is messy due to our architecture. Instead, move it into `unwind::wasm`, which is only compiled for bare-metal targets that default to `panic = "abort"`, rendering the issue moot.
stdarch - Rust's standard library SIMD components
This repository contains the core_arch crate, which implements core::arch - Rust's core library architecture-specific intrinsics.
The std::simd component now lives in the
packed_simd_2 crate.
Synchronizing josh subtree with rustc
This repository is linked to rust-lang/rust as a josh subtree. You can use the rustc-josh-sync tool to perform synchronization.
You can find a guide on how to perform the synchronization here.