rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Stabilize #![feature(target_feature_11)]

Browse Source
This commit is contained in:
Léo Lanteri Thauvin
2022-07-23 14:32:52 +02:00
parent 0d32c8f2ce
commit b379d216ee
28 changed files with 78 additions and 151 deletions
Download Patch File Download Diff File Expand all files Collapse all files

47
compiler/rustc_codegen_ssa/src/codegen_attrs.rs
View File

@@ -268,34 +268,23 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs {
if !tcx.is_closure(did.to_def_id())
&& tcx.fn_sig(did).skip_binder().unsafety() == hir::Unsafety::Normal
{
if tcx.sess.target.is_like_wasm || tcx.sess.opts.actually_rustdoc {
// The `#[target_feature]` attribute is allowed on
// WebAssembly targets on all functions, including safe
// ones. Other targets require that `#[target_feature]` is
// only applied to unsafe functions (pending the
// `target_feature_11` feature) because on most targets
// execution of instructions that are not supported is
// considered undefined behavior. For WebAssembly which is a
// 100% safe target at execution time it's not possible to
// execute undefined instructions, and even if a future
// feature was added in some form for this it would be a
// deterministic trap. There is no undefined behavior when
// executing WebAssembly so `#[target_feature]` is allowed
// on safe functions (but again, only for WebAssembly)
//
// Note that this is also allowed if `actually_rustdoc` so
// if a target is documenting some wasm-specific code then
// it's not spuriously denied.
} else if !tcx.features().target_feature_11 {
let mut err = feature_err(
&tcx.sess.parse_sess,
sym::target_feature_11,
attr.span,
"`#[target_feature(..)]` can only be applied to `unsafe` functions",
);
err.span_label(tcx.def_span(did), "not an `unsafe` function");
err.emit();
} else {
// The `#[target_feature]` attribute is allowed on
// WebAssembly targets on all functions, including safe
// ones. Other targets have conditions on the usage of
// `#[target_feature]` because on most targets
// execution of instructions that are not supported is
// considered undefined behavior. For WebAssembly which is a
// 100% safe target at execution time it's not possible to
// execute undefined instructions, and even if a future
// feature was added in some form for this it would be a
// deterministic trap. There is no undefined behavior when
// executing WebAssembly so `#[target_feature]` is allowed
// on safe functions (but again, only for WebAssembly)
//
// Note that this is also allowed if `actually_rustdoc` so
// if a target is documenting some wasm-specific code then
// it's not spuriously denied.
if !(tcx.sess.target.is_like_wasm || tcx.sess.opts.actually_rustdoc) {
check_target_feature_trait_unsafe(tcx, did, attr.span);
}
}
@@ -533,7 +522,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs {
});
// #73631: closures inherit `#[target_feature]` annotations
if tcx.features().target_feature_11 && tcx.is_closure(did.to_def_id()) {
if tcx.is_closure(did.to_def_id()) {
let owner_id = tcx.parent(did.to_def_id());
if tcx.def_kind(owner_id).has_codegen_attrs() {
codegen_fn_attrs

2
compiler/rustc_feature/src/accepted.rs
View File

@@ -312,6 +312,8 @@ declare_features! (
(accepted, struct_variant, "1.0.0", None, None),
/// Allows `#[target_feature(...)]`.
(accepted, target_feature, "1.27.0", None, None),
/// Allows the use of `#[target_feature]` on safe functions.
(accepted, target_feature_11, "CURRENT_RUSTC_VERSION", Some(69098), None),
/// Allows `fn main()` with return types which implements `Termination` (RFC 1937).
(accepted, termination_trait, "1.26.0", Some(43301), None),
/// Allows `#[test]` functions where the return type implements `Termination` (RFC 1937).

2
compiler/rustc_feature/src/active.rs
View File

@@ -509,8 +509,6 @@ declare_features! (
(active, strict_provenance, "1.61.0", Some(95228), None),
/// Allows string patterns to dereference values to match them.
(active, string_deref_patterns, "1.67.0", Some(87121), None),
/// Allows the use of `#[target_feature]` on safe functions.
(active, target_feature_11, "1.45.0", Some(69098), None),
/// Allows using `#[thread_local]` on `static` items.
(active, thread_local, "1.0.0", Some(29594), None),
/// Allows defining `trait X = A + B;` alias items.