diff --git a/compiler/rustc_error_codes/src/error_codes/E0542.md b/compiler/rustc_error_codes/src/error_codes/E0542.md index 7cb58f9d0cb74..7fecfeaa57c28 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0542.md +++ b/compiler/rustc_error_codes/src/error_codes/E0542.md @@ -10,7 +10,7 @@ Erroneous code example: fn _stable_fn() {} #[rustc_const_stable(feature = "_stable_const_fn")] // invalid -fn _stable_const_fn() {} +const fn _stable_const_fn() {} #[stable(feature = "_deprecated_fn", since = "0.1.0")] #[rustc_deprecated( @@ -29,7 +29,7 @@ To fix this issue, you need to provide the `since` field. Example: fn _stable_fn() {} #[rustc_const_stable(feature = "_stable_const_fn", since = "1.0.0")] // ok! -fn _stable_const_fn() {} +const fn _stable_const_fn() {} #[stable(feature = "_deprecated_fn", since = "0.1.0")] #[rustc_deprecated( diff --git a/compiler/rustc_error_codes/src/error_codes/E0545.md b/compiler/rustc_error_codes/src/error_codes/E0545.md index 9fb935a3ab1ab..7aba084f4d3aa 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0545.md +++ b/compiler/rustc_error_codes/src/error_codes/E0545.md @@ -10,7 +10,7 @@ Erroneous code example: fn _unstable_fn() {} #[rustc_const_unstable(feature = "_unstable_const_fn", issue = "0")] // invalid -fn _unstable_const_fn() {} +const fn _unstable_const_fn() {} ``` To fix this issue, you need to provide a correct value in the `issue` field. @@ -24,7 +24,7 @@ Example: fn _unstable_fn() {} #[rustc_const_unstable(feature = "_unstable_const_fn", issue = "1")] // ok! -fn _unstable_const_fn() {} +const fn _unstable_const_fn() {} ``` See the [How Rust is Made and “Nightly Rust”][how-rust-made-nightly] appendix diff --git a/compiler/rustc_error_codes/src/error_codes/E0547.md b/compiler/rustc_error_codes/src/error_codes/E0547.md index 1aa4b35424884..4950325df6400 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0547.md +++ b/compiler/rustc_error_codes/src/error_codes/E0547.md @@ -10,7 +10,7 @@ Erroneous code example: fn _unstable_fn() {} #[rustc_const_unstable(feature = "_unstable_const_fn")] // invalid -fn _unstable_const_fn() {} +const fn _unstable_const_fn() {} ``` To fix this issue, you need to provide the `issue` field. Example: @@ -26,7 +26,7 @@ fn _unstable_fn() {} feature = "_unstable_const_fn", issue = "none" )] // ok! -fn _unstable_const_fn() {} +const fn _unstable_const_fn() {} ``` See the [How Rust is Made and “Nightly Rust”][how-rust-made-nightly] appendix diff --git a/compiler/rustc_passes/src/stability.rs b/compiler/rustc_passes/src/stability.rs index 5830245e837e4..332da7aa16e8f 100644 --- a/compiler/rustc_passes/src/stability.rs +++ b/compiler/rustc_passes/src/stability.rs @@ -20,6 +20,7 @@ use rustc_session::parse::feature_err; use rustc_session::Session; use rustc_span::symbol::{sym, Symbol}; use rustc_span::{Span, DUMMY_SP}; +use rustc_target::spec::abi::Abi; use std::cmp::Ordering; use std::iter; @@ -95,10 +96,12 @@ struct Annotator<'a, 'tcx> { impl<'a, 'tcx> Annotator<'a, 'tcx> { // Determine the stability for a node based on its attributes and inherited // stability. The stability is recorded in the index and used as the parent. + // If the node is a function, `fn_sig` is its signature fn annotate( &mut self, hir_id: HirId, item_sp: Span, + fn_sig: Option<&'tcx hir::FnSig<'tcx>>, kind: AnnotationKind, inherit_deprecation: InheritDeprecation, inherit_const_stability: InheritConstStability, @@ -164,8 +167,27 @@ impl<'a, 'tcx> Annotator<'a, 'tcx> { let (stab, const_stab) = attr::find_stability(&self.tcx.sess, attrs, item_sp); - let const_stab = const_stab.map(|(const_stab, _)| { + let const_stab = const_stab.map(|(const_stab, const_span)| { let const_stab = self.tcx.intern_const_stability(const_stab); + if let Some(fn_sig) = fn_sig { + if !(fn_sig.header.constness == hir::Constness::Const + && fn_sig.header.abi != Abi::RustIntrinsic + && fn_sig.header.abi != Abi::PlatformIntrinsic) + { + self.tcx + .sess + .struct_span_err( + fn_sig.span, + "attributes `#[rustc_const_unstable]` \ + and `#[rustc_const_stable]` require \ + the function or method to be marked `const`", + ) + .span_help(fn_sig.span, "make the function or method const") + .span_label(const_span, "attribute specified here") + .emit(); + } + } + self.index.const_stab_map.insert(hir_id, const_stab); const_stab }); @@ -367,6 +389,8 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { let orig_in_trait_impl = self.in_trait_impl; let mut kind = AnnotationKind::Required; let mut const_stab_inherit = InheritConstStability::No; + let mut fn_sig = None; + match i.kind { // Inherent impls and foreign modules serve only as containers for other items, // they don't have their own stability. They still can be annotated as unstable @@ -387,6 +411,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { self.annotate( ctor_hir_id, i.span, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -395,12 +420,16 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { ) } } + hir::ItemKind::Fn(ref item_fn_sig, _, _) => { + fn_sig = Some(item_fn_sig); + } _ => {} } self.annotate( i.hir_id(), i.span, + fn_sig, kind, InheritDeprecation::Yes, const_stab_inherit, @@ -411,9 +440,15 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { } fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) { + let fn_sig = match ti.kind { + hir::TraitItemKind::Fn(ref fn_sig, _) => Some(fn_sig), + _ => None, + }; + self.annotate( ti.hir_id(), ti.span, + fn_sig, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -427,9 +462,16 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem<'tcx>) { let kind = if self.in_trait_impl { AnnotationKind::Prohibited } else { AnnotationKind::Required }; + + let fn_sig = match ii.kind { + hir::ImplItemKind::Fn(ref fn_sig, _) => Some(fn_sig), + _ => None, + }; + self.annotate( ii.hir_id(), ii.span, + fn_sig, kind, InheritDeprecation::Yes, InheritConstStability::No, @@ -444,6 +486,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { self.annotate( var.id, var.span, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -453,6 +496,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { v.annotate( ctor_hir_id, var.span, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -470,6 +514,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { self.annotate( s.hir_id, s.span, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -484,6 +529,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { self.annotate( i.hir_id(), i.span, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -498,6 +544,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { self.annotate( md.hir_id(), md.span, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, @@ -517,6 +564,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { self.annotate( p.hir_id, p.span, + None, kind, InheritDeprecation::No, InheritConstStability::No, @@ -687,6 +735,7 @@ fn stability_index(tcx: TyCtxt<'tcx>, (): ()) -> Index<'tcx> { annotator.annotate( hir::CRATE_HIR_ID, krate.item.inner, + None, AnnotationKind::Required, InheritDeprecation::Yes, InheritConstStability::No, diff --git a/src/test/ui/consts/rustc-const-stability-require-const.rs b/src/test/ui/consts/rustc-const-stability-require-const.rs new file mode 100644 index 0000000000000..0f92e7f2cc16f --- /dev/null +++ b/src/test/ui/consts/rustc-const-stability-require-const.rs @@ -0,0 +1,44 @@ +#![crate_type = "lib"] +#![feature(staged_api)] +#![stable(feature = "foo", since = "1.0.0")] + +#[stable(feature = "foo", since = "1.0.0")] +#[rustc_const_unstable(feature = "const_foo", issue = "none")] +pub fn foo() {} +//~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + +#[stable(feature = "bar", since = "1.0.0")] +#[rustc_const_stable(feature = "const_bar", since = "1.0.0")] +pub fn bar() {} +//~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + +#[stable(feature = "potato", since = "1.0.0")] +pub struct Potato; + +impl Potato { + #[stable(feature = "salad", since = "1.0.0")] + #[rustc_const_unstable(feature = "const_salad", issue = "none")] + pub fn salad(&self) -> &'static str { "mmmmmm" } + //~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + + #[stable(feature = "roasted", since = "1.0.0")] + #[rustc_const_unstable(feature = "const_roasted", issue = "none")] + pub fn roasted(&self) -> &'static str { "mmmmmmmmmm" } + //~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` +} + +#[stable(feature = "bar", since = "1.0.0")] +#[rustc_const_stable(feature = "const_bar", since = "1.0.0")] +pub extern "C" fn bar_c() {} +//~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + +#[stable(feature = "foo", since = "1.0.0")] +#[rustc_const_unstable(feature = "const_foo", issue = "none")] +pub extern "C" fn foo_c() {} +//~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + + +#[stable(feature = "foo", since = "1.0.0")] +#[rustc_const_unstable(feature = "const_foo", issue = "none")] +pub extern "stdcall" fn foo_stdcall() {} +//~^ ERROR attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` diff --git a/src/test/ui/consts/rustc-const-stability-require-const.stderr b/src/test/ui/consts/rustc-const-stability-require-const.stderr new file mode 100644 index 0000000000000..7e6f2870997b8 --- /dev/null +++ b/src/test/ui/consts/rustc-const-stability-require-const.stderr @@ -0,0 +1,100 @@ +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:7:1 + | +LL | #[rustc_const_unstable(feature = "const_foo", issue = "none")] + | -------------------------------------------------------------- attribute specified here +LL | pub fn foo() {} + | ^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:7:1 + | +LL | pub fn foo() {} + | ^^^^^^^^^^^^ + +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:12:1 + | +LL | #[rustc_const_stable(feature = "const_bar", since = "1.0.0")] + | ------------------------------------------------------------- attribute specified here +LL | pub fn bar() {} + | ^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:12:1 + | +LL | pub fn bar() {} + | ^^^^^^^^^^^^ + +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:21:5 + | +LL | #[rustc_const_unstable(feature = "const_salad", issue = "none")] + | ---------------------------------------------------------------- attribute specified here +LL | pub fn salad(&self) -> &'static str { "mmmmmm" } + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:21:5 + | +LL | pub fn salad(&self) -> &'static str { "mmmmmm" } + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:26:5 + | +LL | #[rustc_const_unstable(feature = "const_roasted", issue = "none")] + | ------------------------------------------------------------------ attribute specified here +LL | pub fn roasted(&self) -> &'static str { "mmmmmmmmmm" } + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:26:5 + | +LL | pub fn roasted(&self) -> &'static str { "mmmmmmmmmm" } + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:32:1 + | +LL | #[rustc_const_stable(feature = "const_bar", since = "1.0.0")] + | ------------------------------------------------------------- attribute specified here +LL | pub extern "C" fn bar_c() {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:32:1 + | +LL | pub extern "C" fn bar_c() {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:37:1 + | +LL | #[rustc_const_unstable(feature = "const_foo", issue = "none")] + | -------------------------------------------------------------- attribute specified here +LL | pub extern "C" fn foo_c() {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:37:1 + | +LL | pub extern "C" fn foo_c() {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be marked `const` + --> $DIR/rustc-const-stability-require-const.rs:43:1 + | +LL | #[rustc_const_unstable(feature = "const_foo", issue = "none")] + | -------------------------------------------------------------- attribute specified here +LL | pub extern "stdcall" fn foo_stdcall() {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: make the function or method const + --> $DIR/rustc-const-stability-require-const.rs:43:1 + | +LL | pub extern "stdcall" fn foo_stdcall() {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 7 previous errors +