Rollup merge of #103239 - m-ou-se:unstable-abi-fn-impl-check, r=lcnr

Allow #[unstable] impls for fn() with unstable abi.

This allows `#[unstable]` trait impls for `extern "unwind-C" fn()`, based on the fact that that abi and therefore that type is unstable.

See https://github.com/rust-lang/rust/pull/101263#issuecomment-1283099947
This commit is contained in:
Matthias Krüger 2022-10-19 21:38:41 +02:00 committed by GitHub
commit 12775ce16a
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4 changed files with 154 additions and 165 deletions

View file

@ -891,8 +891,25 @@ impl<'tcx> Visitor<'tcx> for CheckTraitImplStable<'tcx> {
if let TyKind::Never = t.kind { if let TyKind::Never = t.kind {
self.fully_stable = false; self.fully_stable = false;
} }
if let TyKind::BareFn(f) = t.kind {
if rustc_target::spec::abi::is_stable(f.abi.name()).is_err() {
self.fully_stable = false;
}
}
intravisit::walk_ty(self, t) intravisit::walk_ty(self, t)
} }
fn visit_fn_decl(&mut self, fd: &'tcx hir::FnDecl<'tcx>) {
for ty in fd.inputs {
self.visit_ty(ty)
}
if let hir::FnRetTy::Return(output_ty) = fd.output {
match output_ty.kind {
TyKind::Never => {} // `-> !` is stable
_ => self.visit_ty(output_ty),
}
}
}
} }
/// Given the list of enabled features that were not language features (i.e., that /// Given the list of enabled features that were not language features (i.e., that

View file

@ -109,175 +109,125 @@ pub enum AbiDisabled {
Unrecognized, Unrecognized,
} }
fn gate_feature_post(
features: &rustc_feature::Features,
feature: Symbol,
span: Span,
explain: &'static str,
) -> Result<(), AbiDisabled> {
if !features.enabled(feature) && !span.allows_unstable(feature) {
Err(AbiDisabled::Unstable { feature, explain })
} else {
Ok(())
}
}
pub fn is_enabled( pub fn is_enabled(
features: &rustc_feature::Features, features: &rustc_feature::Features,
span: Span, span: Span,
name: &str, name: &str,
) -> Result<(), AbiDisabled> { ) -> Result<(), AbiDisabled> {
let s = is_stable(name);
if let Err(AbiDisabled::Unstable { feature, .. }) = s {
if features.enabled(feature) || span.allows_unstable(feature) {
return Ok(());
}
}
s
}
pub fn is_stable(name: &str) -> Result<(), AbiDisabled> {
match name { match name {
// Stable // Stable
"Rust" | "C" | "cdecl" | "stdcall" | "fastcall" | "aapcs" | "win64" | "sysv64" "Rust" | "C" | "cdecl" | "stdcall" | "fastcall" | "aapcs" | "win64" | "sysv64"
| "system" => Ok(()), | "system" => Ok(()),
"rust-intrinsic" => { "rust-intrinsic" => Err(AbiDisabled::Unstable {
gate_feature_post(features, sym::intrinsics, span, "intrinsics are subject to change") feature: sym::intrinsics,
} explain: "intrinsics are subject to change",
"platform-intrinsic" => gate_feature_post( }),
features, "platform-intrinsic" => Err(AbiDisabled::Unstable {
sym::platform_intrinsics, feature: sym::platform_intrinsics,
span, explain: "platform intrinsics are experimental and possibly buggy",
"platform intrinsics are experimental and possibly buggy", }),
), "vectorcall" => Err(AbiDisabled::Unstable {
"vectorcall" => gate_feature_post( feature: sym::abi_vectorcall,
features, explain: "vectorcall is experimental and subject to change",
sym::abi_vectorcall, }),
span, "thiscall" => Err(AbiDisabled::Unstable {
"vectorcall is experimental and subject to change", feature: sym::abi_thiscall,
), explain: "thiscall is experimental and subject to change",
"thiscall" => gate_feature_post( }),
features, "rust-call" => Err(AbiDisabled::Unstable {
sym::abi_thiscall, feature: sym::unboxed_closures,
span, explain: "rust-call ABI is subject to change",
"thiscall is experimental and subject to change", }),
), "rust-cold" => Err(AbiDisabled::Unstable {
"rust-call" => gate_feature_post( feature: sym::rust_cold_cc,
features, explain: "rust-cold is experimental and subject to change",
sym::unboxed_closures, }),
span, "ptx-kernel" => Err(AbiDisabled::Unstable {
"rust-call ABI is subject to change", feature: sym::abi_ptx,
), explain: "PTX ABIs are experimental and subject to change",
"rust-cold" => gate_feature_post( }),
features, "unadjusted" => Err(AbiDisabled::Unstable {
sym::rust_cold_cc, feature: sym::abi_unadjusted,
span, explain: "unadjusted ABI is an implementation detail and perma-unstable",
"rust-cold is experimental and subject to change", }),
), "msp430-interrupt" => Err(AbiDisabled::Unstable {
"ptx-kernel" => gate_feature_post( feature: sym::abi_msp430_interrupt,
features, explain: "msp430-interrupt ABI is experimental and subject to change",
sym::abi_ptx, }),
span, "x86-interrupt" => Err(AbiDisabled::Unstable {
"PTX ABIs are experimental and subject to change", feature: sym::abi_x86_interrupt,
), explain: "x86-interrupt ABI is experimental and subject to change",
"unadjusted" => gate_feature_post( }),
features, "amdgpu-kernel" => Err(AbiDisabled::Unstable {
sym::abi_unadjusted, feature: sym::abi_amdgpu_kernel,
span, explain: "amdgpu-kernel ABI is experimental and subject to change",
"unadjusted ABI is an implementation detail and perma-unstable", }),
), "avr-interrupt" | "avr-non-blocking-interrupt" => Err(AbiDisabled::Unstable {
"msp430-interrupt" => gate_feature_post( feature: sym::abi_avr_interrupt,
features, explain: "avr-interrupt and avr-non-blocking-interrupt ABIs are experimental and subject to change",
sym::abi_msp430_interrupt, }),
span, "efiapi" => Err(AbiDisabled::Unstable {
"msp430-interrupt ABI is experimental and subject to change", feature: sym::abi_efiapi,
), explain: "efiapi ABI is experimental and subject to change",
"x86-interrupt" => gate_feature_post( }),
features, "C-cmse-nonsecure-call" => Err(AbiDisabled::Unstable {
sym::abi_x86_interrupt, feature: sym::abi_c_cmse_nonsecure_call,
span, explain: "C-cmse-nonsecure-call ABI is experimental and subject to change",
"x86-interrupt ABI is experimental and subject to change", }),
), "C-unwind" => Err(AbiDisabled::Unstable {
"amdgpu-kernel" => gate_feature_post( feature: sym::c_unwind,
features, explain: "C-unwind ABI is experimental and subject to change",
sym::abi_amdgpu_kernel, }),
span, "stdcall-unwind" => Err(AbiDisabled::Unstable {
"amdgpu-kernel ABI is experimental and subject to change", feature: sym::c_unwind,
), explain: "stdcall-unwind ABI is experimental and subject to change",
"avr-interrupt" | "avr-non-blocking-interrupt" => gate_feature_post( }),
features, "system-unwind" => Err(AbiDisabled::Unstable {
sym::abi_avr_interrupt, feature: sym::c_unwind,
span, explain: "system-unwind ABI is experimental and subject to change",
"avr-interrupt and avr-non-blocking-interrupt ABIs are experimental and subject to change", }),
), "thiscall-unwind" => Err(AbiDisabled::Unstable {
"efiapi" => gate_feature_post( feature: sym::c_unwind,
features, explain: "thiscall-unwind ABI is experimental and subject to change",
sym::abi_efiapi, }),
span, "cdecl-unwind" => Err(AbiDisabled::Unstable {
"efiapi ABI is experimental and subject to change", feature: sym::c_unwind,
), explain: "cdecl-unwind ABI is experimental and subject to change",
"C-cmse-nonsecure-call" => gate_feature_post( }),
features, "fastcall-unwind" => Err(AbiDisabled::Unstable {
sym::abi_c_cmse_nonsecure_call, feature: sym::c_unwind,
span, explain: "fastcall-unwind ABI is experimental and subject to change",
"C-cmse-nonsecure-call ABI is experimental and subject to change", }),
), "vectorcall-unwind" => Err(AbiDisabled::Unstable {
"C-unwind" => gate_feature_post( feature: sym::c_unwind,
features, explain: "vectorcall-unwind ABI is experimental and subject to change",
sym::c_unwind, }),
span, "aapcs-unwind" => Err(AbiDisabled::Unstable {
"C-unwind ABI is experimental and subject to change", feature: sym::c_unwind,
), explain: "aapcs-unwind ABI is experimental and subject to change",
"stdcall-unwind" => gate_feature_post( }),
features, "win64-unwind" => Err(AbiDisabled::Unstable {
sym::c_unwind, feature: sym::c_unwind,
span, explain: "win64-unwind ABI is experimental and subject to change",
"stdcall-unwind ABI is experimental and subject to change", }),
), "sysv64-unwind" => Err(AbiDisabled::Unstable {
"system-unwind" => gate_feature_post( feature: sym::c_unwind,
features, explain: "sysv64-unwind ABI is experimental and subject to change",
sym::c_unwind, }),
span, "wasm" => Err(AbiDisabled::Unstable {
"system-unwind ABI is experimental and subject to change", feature: sym::wasm_abi,
), explain: "wasm ABI is experimental and subject to change",
"thiscall-unwind" => gate_feature_post( }),
features,
sym::c_unwind,
span,
"thiscall-unwind ABI is experimental and subject to change",
),
"cdecl-unwind" => gate_feature_post(
features,
sym::c_unwind,
span,
"cdecl-unwind ABI is experimental and subject to change",
),
"fastcall-unwind" => gate_feature_post(
features,
sym::c_unwind,
span,
"fastcall-unwind ABI is experimental and subject to change",
),
"vectorcall-unwind" => gate_feature_post(
features,
sym::c_unwind,
span,
"vectorcall-unwind ABI is experimental and subject to change",
),
"aapcs-unwind" => gate_feature_post(
features,
sym::c_unwind,
span,
"aapcs-unwind ABI is experimental and subject to change",
),
"win64-unwind" => gate_feature_post(
features,
sym::c_unwind,
span,
"win64-unwind ABI is experimental and subject to change",
),
"sysv64-unwind" => gate_feature_post(
features,
sym::c_unwind,
span,
"sysv64-unwind ABI is experimental and subject to change",
),
"wasm" => gate_feature_post(
features,
sym::wasm_abi,
span,
"wasm ABI is experimental and subject to change",
),
_ => Err(AbiDisabled::Unrecognized), _ => Err(AbiDisabled::Unrecognized),
} }
} }

View file

@ -1,4 +1,4 @@
#![feature(staged_api)] #![feature(staged_api, never_type, c_unwind)]
//~^ ERROR module has missing stability attribute //~^ ERROR module has missing stability attribute
#[stable(feature = "a", since = "1")] #[stable(feature = "a", since = "1")]
@ -23,7 +23,21 @@ impl StableTrait for UnstableType {}
impl UnstableTrait for StableType {} impl UnstableTrait for StableType {}
#[unstable(feature = "h", issue = "none")] #[unstable(feature = "h", issue = "none")]
impl StableTrait for ! {}
// Note: If C-unwind is stabilized, switch this to another (unstable) ABI.
#[unstable(feature = "i", issue = "none")]
impl StableTrait for extern "C-unwind" fn() {}
#[unstable(feature = "j", issue = "none")]
//~^ ERROR an `#[unstable]` annotation here has no effect [ineffective_unstable_trait_impl] //~^ ERROR an `#[unstable]` annotation here has no effect [ineffective_unstable_trait_impl]
impl StableTrait for StableType {} impl StableTrait for StableType {}
#[unstable(feature = "k", issue = "none")]
//~^ ERROR an `#[unstable]` annotation here has no effect [ineffective_unstable_trait_impl]
impl StableTrait for fn() -> ! {}
#[unstable(feature = "l", issue = "none")]
impl StableTrait for fn() -> UnstableType {}
fn main() {} fn main() {}

View file

@ -1,16 +1,24 @@
error: an `#[unstable]` annotation here has no effect error: an `#[unstable]` annotation here has no effect
--> $DIR/stability-attribute-trait-impl.rs:25:1 --> $DIR/stability-attribute-trait-impl.rs:32:1
| |
LL | #[unstable(feature = "h", issue = "none")] LL | #[unstable(feature = "j", issue = "none")]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| |
= note: see issue #55436 <https://github.com/rust-lang/rust/issues/55436> for more information = note: see issue #55436 <https://github.com/rust-lang/rust/issues/55436> for more information
= note: `#[deny(ineffective_unstable_trait_impl)]` on by default = note: `#[deny(ineffective_unstable_trait_impl)]` on by default
error: an `#[unstable]` annotation here has no effect
--> $DIR/stability-attribute-trait-impl.rs:36:1
|
LL | #[unstable(feature = "k", issue = "none")]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #55436 <https://github.com/rust-lang/rust/issues/55436> for more information
error: module has missing stability attribute error: module has missing stability attribute
--> $DIR/stability-attribute-trait-impl.rs:1:1 --> $DIR/stability-attribute-trait-impl.rs:1:1
| |
LL | / #![feature(staged_api)] LL | / #![feature(staged_api, never_type, c_unwind)]
LL | | LL | |
LL | | LL | |
LL | | #[stable(feature = "a", since = "1")] LL | | #[stable(feature = "a", since = "1")]
@ -19,5 +27,5 @@ LL | |
LL | | fn main() {} LL | | fn main() {}
| |____________^ | |____________^
error: aborting due to 2 previous errors error: aborting due to 3 previous errors