diff --git a/compiler/rustc_codegen_cranelift/example/mini_core.rs b/compiler/rustc_codegen_cranelift/example/mini_core.rs index a79909ce0c8..47db7ee3691 100644 --- a/compiler/rustc_codegen_cranelift/example/mini_core.rs +++ b/compiler/rustc_codegen_cranelift/example/mini_core.rs @@ -8,6 +8,7 @@ rustc_attrs, transparent_unions, auto_traits, + freeze_impls, thread_local )] #![no_core] diff --git a/compiler/rustc_codegen_gcc/example/mini_core.rs b/compiler/rustc_codegen_gcc/example/mini_core.rs index 230009741dc..1f364f78ece 100644 --- a/compiler/rustc_codegen_gcc/example/mini_core.rs +++ b/compiler/rustc_codegen_gcc/example/mini_core.rs @@ -1,6 +1,6 @@ #![feature( no_core, lang_items, intrinsics, unboxed_closures, type_ascription, extern_types, - decl_macro, rustc_attrs, transparent_unions, auto_traits, + decl_macro, rustc_attrs, transparent_unions, auto_traits, freeze_impls, thread_local )] #![no_core] diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs index 53254d567cc..db192ae9a35 100644 --- a/compiler/rustc_feature/src/unstable.rs +++ b/compiler/rustc_feature/src/unstable.rs @@ -469,6 +469,8 @@ pub fn internal(&self, feature: Symbol) -> bool { (unstable, fn_align, "1.53.0", Some(82232)), /// Support delegating implementation of functions to other already implemented functions. (incomplete, fn_delegation, "1.76.0", Some(118212)), + /// Allows impls for the Freeze trait. + (internal, freeze_impls, "CURRENT_RUSTC_VERSION", Some(121675)), /// Allows defining gen blocks and `gen fn`. (unstable, gen_blocks, "1.75.0", Some(117078)), /// Infer generic args for both consts and types. diff --git a/compiler/rustc_hir_analysis/src/coherence/mod.rs b/compiler/rustc_hir_analysis/src/coherence/mod.rs index d6281fa08f7..52acc10b9fe 100644 --- a/compiler/rustc_hir_analysis/src/coherence/mod.rs +++ b/compiler/rustc_hir_analysis/src/coherence/mod.rs @@ -10,6 +10,7 @@ use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::query::Providers; use rustc_middle::ty::{self, TyCtxt, TypeVisitableExt}; +use rustc_session::parse::feature_err; use rustc_span::{sym, ErrorGuaranteed}; use rustc_trait_selection::traits; @@ -49,6 +50,19 @@ fn enforce_trait_manually_implementable( ) -> Result<(), ErrorGuaranteed> { let impl_header_span = tcx.def_span(impl_def_id); + if tcx.lang_items().freeze_trait() == Some(trait_def_id) { + if !tcx.features().freeze_impls { + feature_err( + &tcx.sess, + sym::freeze_impls, + impl_header_span, + "explicit impls for the `Freeze` trait are not permitted", + ) + .with_span_label(impl_header_span, format!("impl of `Freeze` not allowed")) + .emit(); + } + } + // Disallow *all* explicit impls of traits marked `#[rustc_deny_explicit_impl]` if trait_def.deny_explicit_impl { let trait_name = tcx.item_name(trait_def_id); diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 4d8475bef54..f52f187973f 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -841,6 +841,7 @@ format_placeholder, format_unsafe_arg, freeze, + freeze_impls, freg, frem_algebraic, frem_fast, diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs index 7b735d48bdf..6ea7fda1538 100644 --- a/library/core/src/lib.rs +++ b/library/core/src/lib.rs @@ -203,6 +203,7 @@ // Language features: // tidy-alphabetical-start #![cfg_attr(bootstrap, feature(platform_intrinsics))] +#![cfg_attr(not(bootstrap), feature(freeze_impls))] #![feature(abi_unadjusted)] #![feature(adt_const_params)] #![feature(allow_internal_unsafe)] diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs index c5cacd12f70..a56a2578c22 100644 --- a/library/core/src/marker.rs +++ b/library/core/src/marker.rs @@ -818,13 +818,13 @@ pub trait DiscriminantKind { /// will not contain interior mutability, and subsequently allow /// placing the constant behind references. #[lang = "freeze"] -#[unstable(feature = "freeze", issue = "60715")] +#[unstable(feature = "freeze", issue = "121675")] pub unsafe auto trait Freeze {} -#[unstable(feature = "freeze", issue = "60715")] +#[unstable(feature = "freeze", issue = "121675")] impl !Freeze for UnsafeCell {} marker_impls! { - #[unstable(feature = "freeze", issue = "60715")] + #[unstable(feature = "freeze", issue = "121675")] unsafe Freeze for {T: ?Sized} PhantomData, {T: ?Sized} *const T, diff --git a/tests/run-make/min-global-align/min_global_align.rs b/tests/run-make/min-global-align/min_global_align.rs index 135792e9372..cd1ef8cb351 100644 --- a/tests/run-make/min-global-align/min_global_align.rs +++ b/tests/run-make/min-global-align/min_global_align.rs @@ -1,4 +1,4 @@ -#![feature(no_core, lang_items)] +#![feature(no_core, lang_items, freeze_impls)] #![crate_type = "rlib"] #![no_core] diff --git a/tests/ui/feature-gates/feature-gate-freeze-impls.rs b/tests/ui/feature-gates/feature-gate-freeze-impls.rs new file mode 100644 index 00000000000..c14c9494874 --- /dev/null +++ b/tests/ui/feature-gates/feature-gate-freeze-impls.rs @@ -0,0 +1,15 @@ +#![feature(freeze, negative_impls)] + +use std::marker::Freeze; + +struct Foo; + +unsafe impl Freeze for Foo {} +//~^ explicit impls for the `Freeze` trait are not permitted + +struct Bar; + +impl !Freeze for Bar {} +//~^ explicit impls for the `Freeze` trait are not permitted + +fn main() {} diff --git a/tests/ui/feature-gates/feature-gate-freeze-impls.stderr b/tests/ui/feature-gates/feature-gate-freeze-impls.stderr new file mode 100644 index 00000000000..eef524fe78e --- /dev/null +++ b/tests/ui/feature-gates/feature-gate-freeze-impls.stderr @@ -0,0 +1,23 @@ +error[E0658]: explicit impls for the `Freeze` trait are not permitted + --> $DIR/feature-gate-freeze-impls.rs:7:1 + | +LL | unsafe impl Freeze for Foo {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ impl of `Freeze` not allowed + | + = note: see issue #121675 for more information + = help: add `#![feature(freeze_impls)]` 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]: explicit impls for the `Freeze` trait are not permitted + --> $DIR/feature-gate-freeze-impls.rs:12:1 + | +LL | impl !Freeze for Bar {} + | ^^^^^^^^^^^^^^^^^^^^ impl of `Freeze` not allowed + | + = note: see issue #121675 for more information + = help: add `#![feature(freeze_impls)]` 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`.