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Auto merge of #129753 - folkertdev:stabilize-const-extern-fn, r=RalfJung

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stabilize `const_extern_fn`

closes https://github.com/rust-lang/rust/issues/64926

tracking issue: https://github.com/rust-lang/rust/issues/64926
reference PR: https://github.com/rust-lang/reference/pull/1596

## Stabilizaton Report

### Summary

Using `const extern "Rust"` and `const extern "C"` was already stabilized (since version 1.62.0, see https://github.com/rust-lang/rust/pull/95346). This PR stabilizes the other calling conventions: it is now possible to write  `const unsafe extern "calling-convention" fn` and `const extern "calling-convention" fn` for any supported calling convention:

```rust
const extern "C-unwind" fn foo1(val: u8) -> u8 { val + 1}
const extern "stdcall" fn foo2(val: u8) -> u8 { val + 1}
const unsafe extern "C-unwind" fn bar1(val: bool) -> bool { !val }
const unsafe extern "stdcall" fn bar2(val: bool) -> bool { !val }
```

This can be used to const-ify an `extern fn`, or conversely, to make a `const fn` callable from external code.

r? T-lang

cc `@RalfJung`
This commit is contained in:
bors 2024-09-14 23:47:59 +00:00
commit 4f1be92153
29 changed files with 186 additions and 235 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
compiler/rustc_ast_passes/src/feature_gate.rs
View File

@ -75,22 +75,9 @@ struct PostExpansionVisitor<'a> {
impl<'a> PostExpansionVisitor<'a> {
#[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable
fn check_abi(&self, abi: ast::StrLit, constness: ast::Const) {
fn check_abi(&self, abi: ast::StrLit) {
let ast::StrLit { symbol_unescaped, span, .. } = abi;
if let ast::Const::Yes(_) = constness {
match symbol_unescaped {
// Stable
sym::Rust | sym::C => {}
abi => gate!(
&self,
const_extern_fn,
span,
format!("`{}` as a `const fn` ABI is unstable", abi)
),
}
}
match abi::is_enabled(self.features, span, symbol_unescaped.as_str()) {
Ok(()) => (),
Err(abi::AbiDisabled::Unstable { feature, explain }) => {
@ -110,9 +97,9 @@ fn check_abi(&self, abi: ast::StrLit, constness: ast::Const) {
}
}
fn check_extern(&self, ext: ast::Extern, constness: ast::Const) {
fn check_extern(&self, ext: ast::Extern) {
if let ast::Extern::Explicit(abi, _) = ext {
self.check_abi(abi, constness);
self.check_abi(abi);
}
}
@ -239,7 +226,7 @@ fn visit_item(&mut self, i: &'a ast::Item) {
match &i.kind {
ast::ItemKind::ForeignMod(foreign_module) => {
if let Some(abi) = foreign_module.abi {
self.check_abi(abi, ast::Const::No);
self.check_abi(abi);
}
}
@ -341,7 +328,7 @@ fn visit_ty(&mut self, ty: &'a ast::Ty) {
match &ty.kind {
ast::TyKind::BareFn(bare_fn_ty) => {
// Function pointers cannot be `const`
self.check_extern(bare_fn_ty.ext, ast::Const::No);
self.check_extern(bare_fn_ty.ext);
self.check_late_bound_lifetime_defs(&bare_fn_ty.generic_params);
}
ast::TyKind::Never => {
@ -446,7 +433,7 @@ fn visit_poly_trait_ref(&mut self, t: &'a ast::PolyTraitRef) {
fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) {
if let Some(header) = fn_kind.header() {
// Stability of const fn methods are covered in `visit_assoc_item` below.
self.check_extern(header.ext, header.constness);
self.check_extern(header.ext);
}
if let FnKind::Closure(ast::ClosureBinder::For { generic_params, .. }, ..) = fn_kind {

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

@ -115,6 +115,8 @@ macro_rules! declare_features {
(accepted, conservative_impl_trait, "1.26.0", Some(34511)),
/// Allows calling constructor functions in `const fn`.
(accepted, const_constructor, "1.40.0", Some(61456)),
/// Allows the definition of `const extern fn` and `const unsafe extern fn`.
(accepted, const_extern_fn, "CURRENT_RUSTC_VERSION", Some(64926)),
/// Allows basic arithmetic on floating point types in a `const fn`.
(accepted, const_fn_floating_point_arithmetic, "1.82.0", Some(57241)),
/// Allows using and casting function pointers in a `const fn`.

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

@ -401,8 +401,6 @@ pub fn internal(&self, feature: Symbol) -> bool {
(unstable, const_async_blocks, "1.53.0", Some(85368)),
/// Allows `const || {}` closures in const contexts.
(incomplete, const_closures, "1.68.0", Some(106003)),
/// Allows the definition of `const extern fn` and `const unsafe extern fn`.
(unstable, const_extern_fn, "1.40.0", Some(64926)),
/// Allows `for _ in _` loops in const contexts.
(unstable, const_for, "1.56.0", Some(87575)),
/// Allows using `&mut` in constant functions.

3
compiler/rustc_parse/src/parser/ty.rs
View File

@ -607,9 +607,6 @@ fn parse_ty_bare_fn(
let decl = self.parse_fn_decl(|_| false, AllowPlus::No, recover_return_sign)?;
let whole_span = lo.to(self.prev_token.span);
if let ast::Const::Yes(span) = constness {
// If we ever start to allow `const fn()`, then update
// feature gating for `#![feature(const_extern_fn)]` to
// cover it.
self.dcx().emit_err(FnPointerCannotBeConst { span: whole_span, qualifier: span });
}
if let Some(ast::CoroutineKind::Async { span, .. }) = coroutine_kind {

3
src/tools/clippy/clippy_config/src/msrvs.rs
View File

@ -17,6 +17,7 @@ macro_rules! msrv_aliases {
// names may refer to stabilized feature flags or library items
msrv_aliases! {
1,83,0 { CONST_EXTERN_FN }
1,83,0 { CONST_FLOAT_BITS_CONV }
1,81,0 { LINT_REASONS_STABILIZATION }
1,80,0 { BOX_INTO_ITER}
@ -27,7 +28,7 @@ macro_rules! msrv_aliases {
1,68,0 { PATH_MAIN_SEPARATOR_STR }
1,65,0 { LET_ELSE, POINTER_CAST_CONSTNESS }
1,63,0 { CLONE_INTO }
1,62,0 { BOOL_THEN_SOME, DEFAULT_ENUM_ATTRIBUTE, CONST_EXTERN_FN }
1,62,0 { BOOL_THEN_SOME, DEFAULT_ENUM_ATTRIBUTE, CONST_EXTERN_C_FN }
1,59,0 { THREAD_LOCAL_CONST_INIT }
1,58,0 { FORMAT_ARGS_CAPTURE, PATTERN_TRAIT_CHAR_ARRAY, CONST_RAW_PTR_DEREF }
1,56,0 { CONST_FN_UNION }

10
src/tools/clippy/clippy_lints/src/missing_const_for_fn.rs
View File

@ -119,9 +119,7 @@ fn check_fn(
.iter()
.any(|param| matches!(param.kind, GenericParamKind::Const { .. }));
if already_const(header)
|| has_const_generic_params
|| !could_be_const_with_abi(cx, &self.msrv, header.abi)
if already_const(header) || has_const_generic_params || !could_be_const_with_abi(&self.msrv, header.abi)
{
return;
}
@ -183,13 +181,13 @@ fn already_const(header: hir::FnHeader) -> bool {
header.constness == Constness::Const
}
fn could_be_const_with_abi(cx: &LateContext<'_>, msrv: &Msrv, abi: Abi) -> bool {
fn could_be_const_with_abi(msrv: &Msrv, abi: Abi) -> bool {
match abi {
Abi::Rust => true,
// `const extern "C"` was stabilized after 1.62.0
Abi::C { unwind: false } => msrv.meets(msrvs::CONST_EXTERN_FN),
Abi::C { unwind: false } => msrv.meets(msrvs::CONST_EXTERN_C_FN),
// Rest ABIs are still unstable and need the `const_extern_fn` feature enabled.
_ => cx.tcx.features().const_extern_fn,
_ => msrv.meets(msrvs::CONST_EXTERN_FN),
}
}

6
src/tools/clippy/tests/ui/missing_const_for_fn/cant_be_const.rs
View File

@ -186,12 +186,6 @@ fn deref_mut_ptr_cannot_be_const(self) -> usize {
extern "C" fn c() {}
}
mod with_extern {
extern "C-unwind" fn c_unwind() {}
extern "system" fn system() {}
extern "system-unwind" fn system_unwind() {}
}
mod with_ty_alias {
type Foo = impl std::fmt::Debug;

14
src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.fixed
View File

@ -1,5 +1,6 @@
#![warn(clippy::missing_const_for_fn)]
#![allow(incomplete_features, clippy::let_and_return, clippy::missing_transmute_annotations)]
#![allow(unsupported_calling_conventions)]
#![feature(const_mut_refs)]
#![feature(const_trait_impl)]
@ -204,3 +205,16 @@ mod with_ty_alias {
// in this test.
const fn alias_ty_is_projection(bar: <() as FooTrait>::Foo) {}
}
mod extern_fn {
const extern "C-unwind" fn c_unwind() {}
//~^ ERROR: this could be a `const fn`
const extern "system" fn system() {}
//~^ ERROR: this could be a `const fn`
const extern "system-unwind" fn system_unwind() {}
//~^ ERROR: this could be a `const fn`
pub const extern "stdcall" fn std_call() {}
//~^ ERROR: this could be a `const fn`
pub const extern "stdcall-unwind" fn std_call_unwind() {}
//~^ ERROR: this could be a `const fn`
}

14
src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.rs
View File

@ -1,5 +1,6 @@
#![warn(clippy::missing_const_for_fn)]
#![allow(incomplete_features, clippy::let_and_return, clippy::missing_transmute_annotations)]
#![allow(unsupported_calling_conventions)]
#![feature(const_mut_refs)]
#![feature(const_trait_impl)]
@ -204,3 +205,16 @@ impl FooTrait for () {
// in this test.
fn alias_ty_is_projection(bar: <() as FooTrait>::Foo) {}
}
mod extern_fn {
extern "C-unwind" fn c_unwind() {}
//~^ ERROR: this could be a `const fn`
extern "system" fn system() {}
//~^ ERROR: this could be a `const fn`
extern "system-unwind" fn system_unwind() {}
//~^ ERROR: this could be a `const fn`
pub extern "stdcall" fn std_call() {}
//~^ ERROR: this could be a `const fn`
pub extern "stdcall-unwind" fn std_call_unwind() {}
//~^ ERROR: this could be a `const fn`
}

99
src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.stderr
View File

@ -1,5 +1,5 @@
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:14:5
--> tests/ui/missing_const_for_fn/could_be_const.rs:15:5
|
LL | / pub fn new() -> Self {
LL | |
@ -16,7 +16,7 @@ LL | pub const fn new() -> Self {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:20:5
--> tests/ui/missing_const_for_fn/could_be_const.rs:21:5
|
LL | / fn const_generic_params<'a, T, const N: usize>(&self, b: &'a [T; N]) -> &'a [T; N] {
LL | |
@ -30,7 +30,7 @@ LL | const fn const_generic_params<'a, T, const N: usize>(&self, b: &'a [T;
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:27:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:28:1
|
LL | / fn one() -> i32 {
LL | |
@ -44,7 +44,7 @@ LL | const fn one() -> i32 {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:33:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:34:1
|
LL | / fn two() -> i32 {
LL | |
@ -59,7 +59,7 @@ LL | const fn two() -> i32 {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:40:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:41:1
|
LL | / fn string() -> String {
LL | |
@ -73,7 +73,7 @@ LL | const fn string() -> String {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:46:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:47:1
|
LL | / unsafe fn four() -> i32 {
LL | |
@ -87,7 +87,7 @@ LL | const unsafe fn four() -> i32 {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:52:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:53:1
|
LL | / fn generic<T>(t: T) -> T {
LL | |
@ -101,7 +101,7 @@ LL | const fn generic<T>(t: T) -> T {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:61:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:62:1
|
LL | / fn generic_arr<T: Copy>(t: [T; 1]) -> T {
LL | |
@ -115,7 +115,7 @@ LL | const fn generic_arr<T: Copy>(t: [T; 1]) -> T {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:75:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:76:9
|
LL | / pub fn b(self, a: &A) -> B {
LL | |
@ -129,7 +129,7 @@ LL | pub const fn b(self, a: &A) -> B {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:85:5
--> tests/ui/missing_const_for_fn/could_be_const.rs:86:5
|
LL | / fn const_fn_stabilized_before_msrv(byte: u8) {
LL | |
@ -143,7 +143,7 @@ LL | const fn const_fn_stabilized_before_msrv(byte: u8) {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:97:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:98:1
|
LL | / fn msrv_1_46() -> i32 {
LL | |
@ -157,7 +157,7 @@ LL | const fn msrv_1_46() -> i32 {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:117:1
--> tests/ui/missing_const_for_fn/could_be_const.rs:118:1
|
LL | fn d(this: D) {}
| ^^^^^^^^^^^^^^^^
@ -168,7 +168,7 @@ LL | const fn d(this: D) {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:125:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:126:9
|
LL | / fn deref_ptr_can_be_const(self) -> usize {
LL | |
@ -182,7 +182,7 @@ LL | const fn deref_ptr_can_be_const(self) -> usize {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:130:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:131:9
|
LL | / fn deref_copied_val(self) -> usize {
LL | |
@ -196,7 +196,7 @@ LL | const fn deref_copied_val(self) -> usize {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:141:5
--> tests/ui/missing_const_for_fn/could_be_const.rs:142:5
|
LL | / fn union_access_can_be_const() {
LL | |
@ -211,7 +211,7 @@ LL | const fn union_access_can_be_const() {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:149:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:150:9
|
LL | extern "C" fn c() {}
| ^^^^^^^^^^^^^^^^^^^^
@ -222,7 +222,7 @@ LL | const extern "C" fn c() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:153:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:154:9
|
LL | extern fn implicit_c() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^
@ -233,7 +233,7 @@ LL | const extern fn implicit_c() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:170:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:171:9
|
LL | / pub fn new(strings: Vec<String>) -> Self {
LL | | Self { strings }
@ -246,7 +246,7 @@ LL | pub const fn new(strings: Vec<String>) -> Self {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:175:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:176:9
|
LL | / pub fn empty() -> Self {
LL | | Self { strings: Vec::new() }
@ -259,7 +259,7 @@ LL | pub const fn empty() -> Self {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:186:9
--> tests/ui/missing_const_for_fn/could_be_const.rs:187:9
|
LL | / pub fn new(text: String) -> Self {
LL | | let vec = Vec::new();
@ -273,7 +273,7 @@ LL | pub const fn new(text: String) -> Self {
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:205:5
--> tests/ui/missing_const_for_fn/could_be_const.rs:206:5
|
LL | fn alias_ty_is_projection(bar: <() as FooTrait>::Foo) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -283,5 +283,60 @@ help: make the function `const`
LL | const fn alias_ty_is_projection(bar: <() as FooTrait>::Foo) {}
| +++++
error: aborting due to 21 previous errors
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:210:5
|
LL | extern "C-unwind" fn c_unwind() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | const extern "C-unwind" fn c_unwind() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:212:5
|
LL | extern "system" fn system() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | const extern "system" fn system() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:214:5
|
LL | extern "system-unwind" fn system_unwind() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | const extern "system-unwind" fn system_unwind() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:216:5
|
LL | pub extern "stdcall" fn std_call() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | pub const extern "stdcall" fn std_call() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const.rs:218:5
|
LL | pub extern "stdcall-unwind" fn std_call_unwind() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | pub const extern "stdcall-unwind" fn std_call_unwind() {}
| +++++
error: aborting due to 26 previous errors

14
src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.fixed
View File

@ -1,14 +0,0 @@
#![warn(clippy::missing_const_for_fn)]
#![allow(unsupported_calling_conventions)]
#![feature(const_extern_fn)]
const extern "C-unwind" fn c_unwind() {}
//~^ ERROR: this could be a `const fn`
const extern "system" fn system() {}
//~^ ERROR: this could be a `const fn`
const extern "system-unwind" fn system_unwind() {}
//~^ ERROR: this could be a `const fn`
pub const extern "stdcall" fn std_call() {}
//~^ ERROR: this could be a `const fn`
pub const extern "stdcall-unwind" fn std_call_unwind() {}
//~^ ERROR: this could be a `const fn`

14
src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.rs
View File

@ -1,14 +0,0 @@
#![warn(clippy::missing_const_for_fn)]
#![allow(unsupported_calling_conventions)]
#![feature(const_extern_fn)]
extern "C-unwind" fn c_unwind() {}
//~^ ERROR: this could be a `const fn`
extern "system" fn system() {}
//~^ ERROR: this could be a `const fn`
extern "system-unwind" fn system_unwind() {}
//~^ ERROR: this could be a `const fn`
pub extern "stdcall" fn std_call() {}
//~^ ERROR: this could be a `const fn`
pub extern "stdcall-unwind" fn std_call_unwind() {}
//~^ ERROR: this could be a `const fn`

59
src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.stderr
View File

@ -1,59 +0,0 @@
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.rs:5:1
|
LL | extern "C-unwind" fn c_unwind() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: `-D clippy::missing-const-for-fn` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::missing_const_for_fn)]`
help: make the function `const`
|
LL | const extern "C-unwind" fn c_unwind() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.rs:7:1
|
LL | extern "system" fn system() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | const extern "system" fn system() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.rs:9:1
|
LL | extern "system-unwind" fn system_unwind() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | const extern "system-unwind" fn system_unwind() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.rs:11:1
|
LL | pub extern "stdcall" fn std_call() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | pub const extern "stdcall" fn std_call() {}
| +++++
error: this could be a `const fn`
--> tests/ui/missing_const_for_fn/could_be_const_with_const_extern_fn.rs:13:1
|
LL | pub extern "stdcall-unwind" fn std_call_unwind() {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: make the function `const`
|
LL | pub const extern "stdcall-unwind" fn std_call_unwind() {}
| +++++
error: aborting due to 5 previous errors

2
tests/ui/consts/const-eval/unwind-abort.rs
View File

@ -1,5 +1,3 @@
#![feature(const_extern_fn)]
const extern "C" fn foo() {
panic!() //~ ERROR evaluation of constant value failed
}

8
tests/ui/consts/const-eval/unwind-abort.stderr
View File

@ -1,16 +1,16 @@
error[E0080]: evaluation of constant value failed
--> $DIR/unwind-abort.rs:4:5
--> $DIR/unwind-abort.rs:2:5
|
LL | panic!()
| ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/unwind-abort.rs:4:5
| ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/unwind-abort.rs:2:5
|
note: inside `foo`
--> $DIR/unwind-abort.rs:4:5
--> $DIR/unwind-abort.rs:2:5
|
LL | panic!()
| ^^^^^^^^
note: inside `_`
--> $DIR/unwind-abort.rs:7:15
--> $DIR/unwind-abort.rs:5:15
|
LL | const _: () = foo();
| ^^^^^

2
tests/ui/consts/const-extern-fn/const-extern-fn-call-extern-fn.rs
View File

@ -1,5 +1,3 @@
#![feature(const_extern_fn)]
extern "C" {
fn regular_in_block();
}

4
tests/ui/consts/const-extern-fn/const-extern-fn-call-extern-fn.stderr
View File

@ -1,5 +1,5 @@
error[E0015]: cannot call non-const fn `regular_in_block` in constant functions
--> $DIR/const-extern-fn-call-extern-fn.rs:9:9
--> $DIR/const-extern-fn-call-extern-fn.rs:7:9
|
LL | regular_in_block();
| ^^^^^^^^^^^^^^^^^^
@ -7,7 +7,7 @@ LL | regular_in_block();
= note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
error[E0015]: cannot call non-const fn `regular` in constant functions
--> $DIR/const-extern-fn-call-extern-fn.rs:18:9
--> $DIR/const-extern-fn-call-extern-fn.rs:16:9
|
LL | regular();
| ^^^^^^^^^

9
tests/ui/consts/const-extern-fn/const-extern-fn-min-const-fn.rs
View File

@ -1,7 +1,6 @@
#![feature(const_extern_fn)]
const extern "C" fn ptr_cast(val: *const u8) { val as usize; }
//~^ ERROR pointers cannot be cast to integers
const extern "C" fn ptr_cast(val: *const u8) {
val as usize;
//~^ ERROR pointers cannot be cast to integers
}
fn main() {}

6
tests/ui/consts/const-extern-fn/const-extern-fn-min-const-fn.stderr
View File

@ -1,8 +1,8 @@
error: pointers cannot be cast to integers during const eval
--> $DIR/const-extern-fn-min-const-fn.rs:3:48
--> $DIR/const-extern-fn-min-const-fn.rs:2:5
|
LL | const extern "C" fn ptr_cast(val: *const u8) { val as usize; }
| ^^^^^^^^^^^^
LL | val as usize;
| ^^^^^^^^^^^^
|
= note: at compile-time, pointers do not have an integer value
= note: avoiding this restriction via `transmute`, `union`, or raw pointers leads to compile-time undefined behavior

10
tests/ui/consts/const-extern-fn/const-extern-fn-requires-unsafe.rs
View File

@ -1,12 +1,18 @@
#![feature(const_extern_fn)]
const unsafe extern "C" fn foo() -> usize {
5
}
const unsafe extern "C-unwind" fn bar() -> usize {
5
}
fn main() {
let a: [u8; foo()];
//~^ call to unsafe function `foo` is unsafe and requires unsafe function or block
foo();
//~^ ERROR call to unsafe function `foo` is unsafe and requires unsafe function or block
let b: [u8; bar()];
//~^ call to unsafe function `bar` is unsafe and requires unsafe function or block
bar();
//~^ ERROR call to unsafe function `bar` is unsafe and requires unsafe function or block
}

22
tests/ui/consts/const-extern-fn/const-extern-fn-requires-unsafe.stderr
View File

@ -1,19 +1,35 @@
error[E0133]: call to unsafe function `foo` is unsafe and requires unsafe function or block
--> $DIR/const-extern-fn-requires-unsafe.rs:10:5
--> $DIR/const-extern-fn-requires-unsafe.rs:12:5
|
LL | foo();
| ^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
error[E0133]: call to unsafe function `bar` is unsafe and requires unsafe function or block
--> $DIR/const-extern-fn-requires-unsafe.rs:16:5
|
LL | bar();
| ^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
error[E0133]: call to unsafe function `foo` is unsafe and requires unsafe function or block
--> $DIR/const-extern-fn-requires-unsafe.rs:8:17
--> $DIR/const-extern-fn-requires-unsafe.rs:10:17
|
LL | let a: [u8; foo()];
| ^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
error: aborting due to 2 previous errors
error[E0133]: call to unsafe function `bar` is unsafe and requires unsafe function or block
--> $DIR/const-extern-fn-requires-unsafe.rs:14:17
|
LL | let b: [u8; bar()];
| ^^^^^ call to unsafe function
|
= note: consult the function's documentation for information on how to avoid undefined behavior
error: aborting due to 4 previous errors
For more information about this error, try `rustc --explain E0133`.

9
tests/ui/consts/const-extern-fn/const-extern-fn.rs
View File

@ -1,5 +1,4 @@
//@ run-pass
#![feature(const_extern_fn)]
const extern "C" fn foo1(val: u8) -> u8 {
val + 1
@ -47,6 +46,10 @@ fn main() {
let _bar2_cast: unsafe extern "C" fn(bool) -> bool = bar2;
unsize(&[0, 1, 2]);
unsafe { closure(); }
unsafe { use_float(); }
unsafe {
closure();
}
unsafe {
use_float();
}
}

13
tests/ui/consts/const-extern-fn/feature-gate-const_extern_fn.rs
View File

@ -1,13 +0,0 @@
// Check that `const extern fn` and `const unsafe extern fn` are feature-gated
// for certain ABIs.
const extern fn foo1() {}
const extern "C" fn foo2() {}
const extern "Rust" fn foo3() {}
const extern "cdecl" fn foo4() {} //~ ERROR `cdecl` as a `const fn` ABI is unstable
const unsafe extern fn bar1() {}
const unsafe extern "C" fn bar2() {}
const unsafe extern "Rust" fn bar3() {}
const unsafe extern "cdecl" fn bar4() {} //~ ERROR `cdecl` as a `const fn` ABI is unstable
fn main() {}

23
tests/ui/consts/const-extern-fn/feature-gate-const_extern_fn.stderr
View File

@ -1,23 +0,0 @@
error[E0658]: `cdecl` as a `const fn` ABI is unstable
--> $DIR/feature-gate-const_extern_fn.rs:7:14
|
LL | const extern "cdecl" fn foo4() {}
| ^^^^^^^
|
= note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
= help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error[E0658]: `cdecl` as a `const fn` ABI is unstable
--> $DIR/feature-gate-const_extern_fn.rs:11:21
|
LL | const unsafe extern "cdecl" fn bar4() {}
| ^^^^^^^
|
= note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
= help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0658`.

2
tests/ui/consts/miri_unleashed/abi-mismatch.rs
View File

@ -1,8 +1,6 @@
// Checks that we report ABI mismatches for "const extern fn"
//@ compile-flags: -Z unleash-the-miri-inside-of-you
#![feature(const_extern_fn)]
const extern "C" fn c_fn() {}
const fn call_rust_fn(my_fn: extern "Rust" fn()) {

8
tests/ui/consts/miri_unleashed/abi-mismatch.stderr
View File

@ -1,16 +1,16 @@
error[E0080]: could not evaluate static initializer
--> $DIR/abi-mismatch.rs:9:5
--> $DIR/abi-mismatch.rs:7:5
|
LL | my_fn();
| ^^^^^^^ calling a function with calling convention C using calling convention Rust
|
note: inside `call_rust_fn`
--> $DIR/abi-mismatch.rs:9:5
--> $DIR/abi-mismatch.rs:7:5
|
LL | my_fn();
| ^^^^^^^
note: inside `VAL`
--> $DIR/abi-mismatch.rs:15:18
--> $DIR/abi-mismatch.rs:13:18
|
LL | static VAL: () = call_rust_fn(unsafe { std::mem::transmute(c_fn as extern "C" fn()) });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -18,7 +18,7 @@ LL | static VAL: () = call_rust_fn(unsafe { std::mem::transmute(c_fn as extern "
warning: skipping const checks
|
help: skipping check that does not even have a feature gate
--> $DIR/abi-mismatch.rs:9:5
--> $DIR/abi-mismatch.rs:7:5
|
LL | my_fn();
| ^^^^^^^

2
tests/ui/consts/unwind-abort.rs
View File

@ -1,7 +1,5 @@
//@ check-pass
#![feature(const_extern_fn)]
// We don't unwind in const-eval anyways.
const extern "C" fn foo() {
panic!()

2
tests/ui/parser/fn-header-semantic-fail.rs
View File

@ -2,8 +2,6 @@
//@ edition:2018
#![feature(const_extern_fn)]
fn main() {
async fn ff1() {} // OK.
unsafe fn ff2() {} // OK.

34
tests/ui/parser/fn-header-semantic-fail.stderr
View File

@ -1,5 +1,5 @@
error: functions cannot be both `const` and `async`
--> $DIR/fn-header-semantic-fail.rs:12:5
--> $DIR/fn-header-semantic-fail.rs:10:5
|
LL | const async unsafe extern "C" fn ff5() {}
| ^^^^^-^^^^^------------------------------
@ -8,7 +8,7 @@ LL | const async unsafe extern "C" fn ff5() {}
| `const` because of this
error[E0379]: functions in traits cannot be declared const
--> $DIR/fn-header-semantic-fail.rs:18:9
--> $DIR/fn-header-semantic-fail.rs:16:9
|
LL | const fn ft3();
| ^^^^^-
@ -17,7 +17,7 @@ LL | const fn ft3();
| help: remove the `const`
error[E0379]: functions in traits cannot be declared const
--> $DIR/fn-header-semantic-fail.rs:20:9
--> $DIR/fn-header-semantic-fail.rs:18:9
|
LL | const async unsafe extern "C" fn ft5();
| ^^^^^-
@ -26,7 +26,7 @@ LL | const async unsafe extern "C" fn ft5();
| help: remove the `const`
error: functions cannot be both `const` and `async`
--> $DIR/fn-header-semantic-fail.rs:20:9
--> $DIR/fn-header-semantic-fail.rs:18:9
|
LL | const async unsafe extern "C" fn ft5();
| ^^^^^-^^^^^----------------------------
@ -35,7 +35,7 @@ LL | const async unsafe extern "C" fn ft5();
| `const` because of this
error[E0379]: functions in trait impls cannot be declared const
--> $DIR/fn-header-semantic-fail.rs:29:9
--> $DIR/fn-header-semantic-fail.rs:27:9
|
LL | const fn ft3() {}
| ^^^^^-
@ -44,7 +44,7 @@ LL | const fn ft3() {}
| help: remove the `const`
error[E0379]: functions in trait impls cannot be declared const
--> $DIR/fn-header-semantic-fail.rs:31:9
--> $DIR/fn-header-semantic-fail.rs:29:9
|
LL | const async unsafe extern "C" fn ft5() {}
| ^^^^^-
@ -53,7 +53,7 @@ LL | const async unsafe extern "C" fn ft5() {}
| help: remove the `const`
error: functions cannot be both `const` and `async`
--> $DIR/fn-header-semantic-fail.rs:31:9
--> $DIR/fn-header-semantic-fail.rs:29:9
|
LL | const async unsafe extern "C" fn ft5() {}
| ^^^^^-^^^^^------------------------------
@ -62,7 +62,7 @@ LL | const async unsafe extern "C" fn ft5() {}
| `const` because of this
error: functions cannot be both `const` and `async`
--> $DIR/fn-header-semantic-fail.rs:41:9
--> $DIR/fn-header-semantic-fail.rs:39:9
|
LL | const async unsafe extern "C" fn fi5() {}
| ^^^^^-^^^^^------------------------------
@ -71,7 +71,7 @@ LL | const async unsafe extern "C" fn fi5() {}
| `const` because of this
error: functions in `extern` blocks cannot have qualifiers
--> $DIR/fn-header-semantic-fail.rs:46:9
--> $DIR/fn-header-semantic-fail.rs:44:9
|
LL | extern "C" {
| ---------- in this `extern` block
@ -79,7 +79,7 @@ LL | async fn fe1();
| ^^^^^ help: remove this qualifier
error: items in unadorned `extern` blocks cannot have safety qualifiers
--> $DIR/fn-header-semantic-fail.rs:47:9
--> $DIR/fn-header-semantic-fail.rs:45:9
|
LL | unsafe fn fe2();
| ^^^^^^^^^^^^^^^^
@ -90,7 +90,7 @@ LL | unsafe extern "C" {
| ++++++
error: functions in `extern` blocks cannot have qualifiers
--> $DIR/fn-header-semantic-fail.rs:48:9
--> $DIR/fn-header-semantic-fail.rs:46:9
|
LL | extern "C" {
| ---------- in this `extern` block
@ -99,7 +99,7 @@ LL | const fn fe3();
| ^^^^^ help: remove this qualifier
error: functions in `extern` blocks cannot have qualifiers
--> $DIR/fn-header-semantic-fail.rs:49:9
--> $DIR/fn-header-semantic-fail.rs:47:9
|
LL | extern "C" {
| ---------- in this `extern` block
@ -108,7 +108,7 @@ LL | extern "C" fn fe4();
| ^^^^^^^^^^ help: remove this qualifier
error: functions in `extern` blocks cannot have qualifiers
--> $DIR/fn-header-semantic-fail.rs:50:15
--> $DIR/fn-header-semantic-fail.rs:48:15
|
LL | extern "C" {
| ---------- in this `extern` block
@ -117,7 +117,7 @@ LL | const async unsafe extern "C" fn fe5();
| ^^^^^ help: remove this qualifier
error: functions in `extern` blocks cannot have qualifiers
--> $DIR/fn-header-semantic-fail.rs:50:9
--> $DIR/fn-header-semantic-fail.rs:48:9
|
LL | extern "C" {
| ---------- in this `extern` block
@ -126,7 +126,7 @@ LL | const async unsafe extern "C" fn fe5();
| ^^^^^ help: remove this qualifier
error: functions in `extern` blocks cannot have qualifiers
--> $DIR/fn-header-semantic-fail.rs:50:28
--> $DIR/fn-header-semantic-fail.rs:48:28
|
LL | extern "C" {
| ---------- in this `extern` block
@ -135,7 +135,7 @@ LL | const async unsafe extern "C" fn fe5();
| ^^^^^^^^^^ help: remove this qualifier
error: items in unadorned `extern` blocks cannot have safety qualifiers
--> $DIR/fn-header-semantic-fail.rs:50:9
--> $DIR/fn-header-semantic-fail.rs:48:9
|
LL | const async unsafe extern "C" fn fe5();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -146,7 +146,7 @@ LL | unsafe extern "C" {
| ++++++
error: functions cannot be both `const` and `async`
--> $DIR/fn-header-semantic-fail.rs:50:9
--> $DIR/fn-header-semantic-fail.rs:48:9
|
LL | const async unsafe extern "C" fn fe5();
| ^^^^^-^^^^^----------------------------