rust/compiler/rustc_codegen_llvm
Nikita Popov 8a50bcbdce Remove extern "wasm" ABI
Remove the unstable `extern "wasm"` ABI (`wasm_abi` feature tracked
in #83788).

As discussed in https://github.com/rust-lang/rust/pull/127513#issuecomment-2220410679
and following, this ABI is a failed experiment that did not end
up being used for anything. Keeping support for this ABI in LLVM 19
would require us to switch wasm targets to the `experimental-mv`
ABI, which we do not want to do.

It should be noted that `Abi::Wasm` was internally used for two
things: The `-Z wasm-c-abi=legacy` ABI that is still used by
default on some wasm targets, and the `extern "wasm"` ABI. Despite
both being `Abi::Wasm` internally, they were not the same. An
explicit `extern "wasm"` additionally enabled the `+multivalue`
feature.

I've opted to remove `Abi::Wasm` in this patch entirely, instead
of keeping it as an ABI with only internal usage. Both
`-Z wasm-c-abi` variants are now treated as part of the normal
C ABI, just with different different treatment in
adjust_for_foreign_abi.
2024-07-11 12:20:26 +02:00
..
src Remove extern "wasm" ABI 2024-07-11 12:20:26 +02:00
Cargo.toml
messages.ftl Use an error struct instead of a panic 2024-05-15 11:14:45 +02:00
README.md

The codegen crate contains the code to convert from MIR into LLVM IR, and then from LLVM IR into machine code. In general it contains code that runs towards the end of the compilation process.

For more information about how codegen works, see the rustc dev guide.