bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Remove extern "wasm" ABI

Browse source 
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.
This commit is contained in:
Nikita Popov 2024-07-10 17:20:21 +02:00
parent 0fdfb61795
commit 8a50bcbdce
25 changed files with 87 additions and 382 deletions
Download patch file Download diff file Expand all files Collapse all files

3
compiler/rustc_ty_utils/src/abi.rs
View file

@ -324,7 +324,7 @@ fn fn_sig_for_fn_abi<'tcx>(
#[inline]
fn conv_from_spec_abi(tcx: TyCtxt<'_>, abi: SpecAbi, c_variadic: bool) -> Conv {
use rustc_target::spec::abi::Abi::*;
match tcx.sess.target.adjust_abi(&tcx, abi, c_variadic) {
match tcx.sess.target.adjust_abi(abi, c_variadic) {
RustIntrinsic | Rust | RustCall => Conv::Rust,
// This is intentionally not using `Conv::Cold`, as that has to preserve
@ -352,7 +352,6 @@ fn conv_from_spec_abi(tcx: TyCtxt<'_>, abi: SpecAbi, c_variadic: bool) -> Conv {
AvrNonBlockingInterrupt => Conv::AvrNonBlockingInterrupt,
RiscvInterruptM => Conv::RiscvInterrupt { kind: RiscvInterruptKind::Machine },
RiscvInterruptS => Conv::RiscvInterrupt { kind: RiscvInterruptKind::Supervisor },
Wasm => Conv::C,
// These API constants ought to be more specific...
Cdecl { .. } => Conv::C,