| //! List of the unstable feature gates. |
| |
| use super::{to_nonzero, Feature}; |
| |
| use rustc_data_structures::fx::FxHashSet; |
| use rustc_span::symbol::{sym, Symbol}; |
| use rustc_span::Span; |
| |
| pub struct UnstableFeature { |
| pub feature: Feature, |
| pub set_enabled: fn(&mut Features), |
| } |
| |
| #[derive(PartialEq)] |
| enum FeatureStatus { |
| Default, |
| Incomplete, |
| Internal, |
| } |
| |
| macro_rules! status_to_enum { |
| (unstable) => { |
| FeatureStatus::Default |
| }; |
| (incomplete) => { |
| FeatureStatus::Incomplete |
| }; |
| (internal) => { |
| FeatureStatus::Internal |
| }; |
| } |
| |
| macro_rules! declare_features { |
| ($( |
| $(#[doc = $doc:tt])* ($status:ident, $feature:ident, $ver:expr, $issue:expr), |
| )+) => { |
| /// Unstable language features that are being implemented or being |
| /// considered for acceptance (stabilization) or removal. |
| pub const UNSTABLE_FEATURES: &[UnstableFeature] = &[ |
| $(UnstableFeature { |
| feature: Feature { |
| name: sym::$feature, |
| since: $ver, |
| issue: to_nonzero($issue), |
| }, |
| // Sets this feature's corresponding bool within `features`. |
| set_enabled: |features| features.$feature = true, |
| }),+ |
| ]; |
| |
| const NUM_FEATURES: usize = UNSTABLE_FEATURES.len(); |
| |
| /// A set of features to be used by later passes. |
| #[derive(Clone, Default, Debug)] |
| pub struct Features { |
| /// `#![feature]` attrs for language features, for error reporting. |
| /// "declared" here means that the feature is actually enabled in the current crate. |
| pub declared_lang_features: Vec<(Symbol, Span, Option<Symbol>)>, |
| /// `#![feature]` attrs for non-language (library) features. |
| /// "declared" here means that the feature is actually enabled in the current crate. |
| pub declared_lib_features: Vec<(Symbol, Span)>, |
| /// `declared_lang_features` + `declared_lib_features`. |
| pub declared_features: FxHashSet<Symbol>, |
| /// Active state of individual features (unstable only). |
| $( |
| $(#[doc = $doc])* |
| pub $feature: bool |
| ),+ |
| } |
| |
| impl Features { |
| pub fn set_declared_lang_feature( |
| &mut self, |
| symbol: Symbol, |
| span: Span, |
| since: Option<Symbol> |
| ) { |
| self.declared_lang_features.push((symbol, span, since)); |
| self.declared_features.insert(symbol); |
| } |
| |
| pub fn set_declared_lib_feature(&mut self, symbol: Symbol, span: Span) { |
| self.declared_lib_features.push((symbol, span)); |
| self.declared_features.insert(symbol); |
| } |
| |
| /// This is intended for hashing the set of active features. |
| /// |
| /// The expectation is that this produces much smaller code than other alternatives. |
| /// |
| /// Note that the total feature count is pretty small, so this is not a huge array. |
| #[inline] |
| pub fn all_features(&self) -> [u8; NUM_FEATURES] { |
| [$(self.$feature as u8),+] |
| } |
| |
| /// Is the given feature explicitly declared, i.e. named in a |
| /// `#![feature(...)]` within the code? |
| pub fn declared(&self, feature: Symbol) -> bool { |
| self.declared_features.contains(&feature) |
| } |
| |
| /// Is the given feature active (enabled by the user)? |
| /// |
| /// Panics if the symbol doesn't correspond to a declared feature. |
| pub fn active(&self, feature: Symbol) -> bool { |
| match feature { |
| $( sym::$feature => self.$feature, )* |
| |
| _ => panic!("`{}` was not listed in `declare_features`", feature), |
| } |
| } |
| |
| /// Some features are known to be incomplete and using them is likely to have |
| /// unanticipated results, such as compiler crashes. We warn the user about these |
| /// to alert them. |
| pub fn incomplete(&self, feature: Symbol) -> bool { |
| match feature { |
| $( |
| sym::$feature => status_to_enum!($status) == FeatureStatus::Incomplete, |
| )* |
| // Accepted/removed features aren't in this file but are never incomplete. |
| _ if self.declared_features.contains(&feature) => false, |
| _ => panic!("`{}` was not listed in `declare_features`", feature), |
| } |
| } |
| |
| /// Some features are internal to the compiler and standard library and should not |
| /// be used in normal projects. We warn the user about these to alert them. |
| pub fn internal(&self, feature: Symbol) -> bool { |
| match feature { |
| $( |
| sym::$feature => status_to_enum!($status) == FeatureStatus::Internal, |
| )* |
| _ if self.declared_features.contains(&feature) => { |
| // This could be accepted/removed, or a libs feature. |
| // Accepted/removed features aren't in this file but are never internal |
| // (a removed feature might have been internal, but that's now irrelevant). |
| // Libs features are internal if they end in `_internal` or `_internals`. |
| // As a special exception we also consider `core_intrinsics` internal; |
| // renaming that age-old feature is just not worth the hassle. |
| // We just always test the name; it's not a big deal if we accidentally hit |
| // an accepted/removed lang feature that way. |
| let name = feature.as_str(); |
| name == "core_intrinsics" || name.ends_with("_internal") || name.ends_with("_internals") |
| } |
| _ => panic!("`{}` was not listed in `declare_features`", feature), |
| } |
| } |
| } |
| }; |
| } |
| |
| // See https://rustc-dev-guide.rust-lang.org/feature-gates.html#feature-gates for more |
| // documentation about handling feature gates. |
| // |
| // If you change this, please modify `src/doc/unstable-book` as well. |
| // |
| // Don't ever remove anything from this list; move them to `accepted.rs` if |
| // accepted or `removed.rs` if removed. |
| // |
| // The version numbers here correspond to the version in which the current status |
| // was set. |
| // |
| // Note that the features are grouped into internal/user-facing and then |
| // sorted alphabetically inside those groups. This is enforced with tidy. |
| // |
| // N.B., `tools/tidy/src/features.rs` parses this information directly out of the |
| // source, so take care when modifying it. |
| |
| #[rustfmt::skip] |
| declare_features! ( |
| // ------------------------------------------------------------------------- |
| // feature-group-start: internal feature gates (no tracking issue) |
| // ------------------------------------------------------------------------- |
| // no-tracking-issue-start |
| |
| /// Allows using the `unadjusted` ABI; perma-unstable. |
| (internal, abi_unadjusted, "1.16.0", None), |
| /// Allows using the `vectorcall` ABI. |
| (unstable, abi_vectorcall, "1.7.0", None), |
| /// Allows using `#![needs_allocator]`, an implementation detail of `#[global_allocator]`. |
| (internal, allocator_internals, "1.20.0", None), |
| /// Allows using `#[allow_internal_unsafe]`. This is an |
| /// attribute on `macro_rules!` and can't use the attribute handling |
| /// below (it has to be checked before expansion possibly makes |
| /// macros disappear). |
| (internal, allow_internal_unsafe, "1.0.0", None), |
| /// Allows using `#[allow_internal_unstable]`. This is an |
| /// attribute on `macro_rules!` and can't use the attribute handling |
| /// below (it has to be checked before expansion possibly makes |
| /// macros disappear). |
| (internal, allow_internal_unstable, "1.0.0", None), |
| /// Allows using anonymous lifetimes in argument-position impl-trait. |
| (unstable, anonymous_lifetime_in_impl_trait, "1.63.0", None), |
| /// Allows identifying the `compiler_builtins` crate. |
| (internal, compiler_builtins, "1.13.0", None), |
| /// Allows writing custom MIR |
| (internal, custom_mir, "1.65.0", None), |
| /// Outputs useful `assert!` messages |
| (unstable, generic_assert, "1.63.0", None), |
| /// Allows using the `rust-intrinsic`'s "ABI". |
| (internal, intrinsics, "1.0.0", None), |
| /// Allows using `#[lang = ".."]` attribute for linking items to special compiler logic. |
| (internal, lang_items, "1.0.0", None), |
| /// Changes `impl Trait` to capture all lifetimes in scope. |
| (unstable, lifetime_capture_rules_2024, "1.76.0", None), |
| /// Allows `#[link(..., cfg(..))]`; perma-unstable per #37406 |
| (unstable, link_cfg, "1.14.0", None), |
| /// Allows the `multiple_supertrait_upcastable` lint. |
| (unstable, multiple_supertrait_upcastable, "1.69.0", None), |
| /// Allow negative trait bounds. This is an internal-only feature for testing the trait solver! |
| (internal, negative_bounds, "1.71.0", None), |
| /// Allows using `#[omit_gdb_pretty_printer_section]`. |
| (internal, omit_gdb_pretty_printer_section, "1.5.0", None), |
| /// Allows using `#[prelude_import]` on glob `use` items. |
| (internal, prelude_import, "1.2.0", None), |
| /// Used to identify crates that contain the profiler runtime. |
| (internal, profiler_runtime, "1.18.0", None), |
| /// Allows using `rustc_*` attributes (RFC 572). |
| (internal, rustc_attrs, "1.0.0", None), |
| /// Allows using the `#[stable]` and `#[unstable]` attributes. |
| (internal, staged_api, "1.0.0", None), |
| /// Added for testing unstable lints; perma-unstable. |
| (internal, test_unstable_lint, "1.60.0", None), |
| /// Use for stable + negative coherence and strict coherence depending on trait's |
| /// rustc_strict_coherence value. |
| (unstable, with_negative_coherence, "1.60.0", None), |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| // Features are listed in alphabetical order. Tidy will fail if you don't keep it this way. |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| |
| // no-tracking-issue-end |
| // ------------------------------------------------------------------------- |
| // feature-group-end: internal feature gates (no tracking issue) |
| // ------------------------------------------------------------------------- |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-start: internal feature gates |
| // ------------------------------------------------------------------------- |
| |
| /// Allows features specific to auto traits. |
| /// Renamed from `optin_builtin_traits`. |
| (unstable, auto_traits, "1.50.0", Some(13231)), |
| /// Allows using `box` in patterns (RFC 469). |
| (unstable, box_patterns, "1.0.0", Some(29641)), |
| /// Allows `#[doc(notable_trait)]`. |
| /// Renamed from `doc_spotlight`. |
| (unstable, doc_notable_trait, "1.52.0", Some(45040)), |
| /// Allows using the `may_dangle` attribute (RFC 1327). |
| (unstable, dropck_eyepatch, "1.10.0", Some(34761)), |
| /// Allows using the `#[fundamental]` attribute. |
| (unstable, fundamental, "1.0.0", Some(29635)), |
| /// Allows using `#[link_name="llvm.*"]`. |
| (internal, link_llvm_intrinsics, "1.0.0", Some(29602)), |
| /// Allows using the `#[linkage = ".."]` attribute. |
| (unstable, linkage, "1.0.0", Some(29603)), |
| /// Allows declaring with `#![needs_panic_runtime]` that a panic runtime is needed. |
| (internal, needs_panic_runtime, "1.10.0", Some(32837)), |
| /// Allows using the `#![panic_runtime]` attribute. |
| (internal, panic_runtime, "1.10.0", Some(32837)), |
| /// Allows `extern "platform-intrinsic" { ... }`. |
| (internal, platform_intrinsics, "1.4.0", Some(27731)), |
| /// Allows using `#[rustc_allow_const_fn_unstable]`. |
| /// This is an attribute on `const fn` for the same |
| /// purpose as `#[allow_internal_unstable]`. |
| (internal, rustc_allow_const_fn_unstable, "1.49.0", Some(69399)), |
| /// Allows using compiler's own crates. |
| (unstable, rustc_private, "1.0.0", Some(27812)), |
| /// Allows using internal rustdoc features like `doc(keyword)`. |
| (internal, rustdoc_internals, "1.58.0", Some(90418)), |
| /// Allows using the `rustdoc::missing_doc_code_examples` lint |
| (unstable, rustdoc_missing_doc_code_examples, "1.31.0", Some(101730)), |
| /// Allows using `#[start]` on a function indicating that it is the program entrypoint. |
| (unstable, start, "1.0.0", Some(29633)), |
| /// Allows using `#[structural_match]` which indicates that a type is structurally matchable. |
| /// FIXME: Subsumed by trait `StructuralPartialEq`, cannot move to removed until a library |
| /// feature with the same name exists. |
| (unstable, structural_match, "1.8.0", Some(31434)), |
| /// Allows using the `rust-call` ABI. |
| (unstable, unboxed_closures, "1.0.0", Some(29625)), |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| // Features are listed in alphabetical order. Tidy will fail if you don't keep it this way. |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-end: internal feature gates |
| // ------------------------------------------------------------------------- |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-start: actual feature gates (target features) |
| // ------------------------------------------------------------------------- |
| |
| // FIXME: Document these and merge with the list below. |
| |
| // Unstable `#[target_feature]` directives. |
| (unstable, aarch64_ver_target_feature, "1.27.0", Some(44839)), |
| (unstable, arm_target_feature, "1.27.0", Some(44839)), |
| (unstable, avx512_target_feature, "1.27.0", Some(44839)), |
| (unstable, bpf_target_feature, "1.54.0", Some(44839)), |
| (unstable, csky_target_feature, "1.73.0", Some(44839)), |
| (unstable, ermsb_target_feature, "1.49.0", Some(44839)), |
| (unstable, hexagon_target_feature, "1.27.0", Some(44839)), |
| (unstable, loongarch_target_feature, "1.73.0", Some(44839)), |
| (unstable, mips_target_feature, "1.27.0", Some(44839)), |
| (unstable, powerpc_target_feature, "1.27.0", Some(44839)), |
| (unstable, riscv_target_feature, "1.45.0", Some(44839)), |
| (unstable, rtm_target_feature, "1.35.0", Some(44839)), |
| (unstable, sse4a_target_feature, "1.27.0", Some(44839)), |
| (unstable, tbm_target_feature, "1.27.0", Some(44839)), |
| (unstable, wasm_target_feature, "1.30.0", Some(44839)), |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| // Features are listed in alphabetical order. Tidy will fail if you don't keep it this way. |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-end: actual feature gates (target features) |
| // ------------------------------------------------------------------------- |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-start: actual feature gates |
| // ------------------------------------------------------------------------- |
| |
| /// Allows `extern "avr-interrupt" fn()` and `extern "avr-non-blocking-interrupt" fn()`. |
| (unstable, abi_avr_interrupt, "1.45.0", Some(69664)), |
| /// Allows `extern "C-cmse-nonsecure-call" fn()`. |
| (unstable, abi_c_cmse_nonsecure_call, "1.51.0", Some(81391)), |
| /// Allows `extern "msp430-interrupt" fn()`. |
| (unstable, abi_msp430_interrupt, "1.16.0", Some(38487)), |
| /// Allows `extern "ptx-*" fn()`. |
| (unstable, abi_ptx, "1.15.0", Some(38788)), |
| /// Allows `extern "riscv-interrupt-m" fn()` and `extern "riscv-interrupt-s" fn()`. |
| (unstable, abi_riscv_interrupt, "1.73.0", Some(111889)), |
| /// Allows `extern "x86-interrupt" fn()`. |
| (unstable, abi_x86_interrupt, "1.17.0", Some(40180)), |
| /// Allows additional const parameter types, such as `&'static str` or user defined types |
| (incomplete, adt_const_params, "1.56.0", Some(95174)), |
| /// Allows defining an `#[alloc_error_handler]`. |
| (unstable, alloc_error_handler, "1.29.0", Some(51540)), |
| /// Allows trait methods with arbitrary self types. |
| (unstable, arbitrary_self_types, "1.23.0", Some(44874)), |
| /// Allows using `const` operands in inline assembly. |
| (unstable, asm_const, "1.58.0", Some(93332)), |
| /// Enables experimental inline assembly support for additional architectures. |
| (unstable, asm_experimental_arch, "1.58.0", Some(93335)), |
| /// Allows the `may_unwind` option in inline assembly. |
| (unstable, asm_unwind, "1.58.0", Some(93334)), |
| /// Allows users to enforce equality of associated constants `TraitImpl<AssocConst=3>`. |
| (unstable, associated_const_equality, "1.58.0", Some(92827)), |
| /// Allows the user of associated type bounds. |
| (unstable, associated_type_bounds, "1.34.0", Some(52662)), |
| /// Allows associated type defaults. |
| (unstable, associated_type_defaults, "1.2.0", Some(29661)), |
| /// Allows `async || body` closures. |
| (unstable, async_closure, "1.37.0", Some(62290)), |
| /// Allows `#[track_caller]` on async functions. |
| (unstable, async_fn_track_caller, "1.73.0", Some(110011)), |
| /// Allows `for await` loops. |
| (unstable, async_for_loop, "1.77.0", Some(118898)), |
| /// Allows builtin # foo() syntax |
| (unstable, builtin_syntax, "1.71.0", Some(110680)), |
| /// Treat `extern "C"` function as nounwind. |
| (unstable, c_unwind, "1.52.0", Some(74990)), |
| /// Allows using C-variadics. |
| (unstable, c_variadic, "1.34.0", Some(44930)), |
| /// Allows the use of `#[cfg(overflow_checks)` to check if integer overflow behaviour. |
| (unstable, cfg_overflow_checks, "1.71.0", Some(111466)), |
| /// Provides the relocation model information as cfg entry |
| (unstable, cfg_relocation_model, "1.73.0", Some(114929)), |
| /// Allows the use of `#[cfg(sanitize = "option")]`; set when -Zsanitizer is used. |
| (unstable, cfg_sanitize, "1.41.0", Some(39699)), |
| /// Allows `cfg(sanitizer_cfi_generalize_pointers)` and `cfg(sanitizer_cfi_normalize_integers)`. |
| (unstable, cfg_sanitizer_cfi, "1.77.0", Some(89653)), |
| /// Allows `cfg(target_abi = "...")`. |
| (unstable, cfg_target_abi, "1.55.0", Some(80970)), |
| /// Allows `cfg(target(abi = "..."))`. |
| (unstable, cfg_target_compact, "1.63.0", Some(96901)), |
| /// Allows `cfg(target_has_atomic_load_store = "...")`. |
| (unstable, cfg_target_has_atomic, "1.60.0", Some(94039)), |
| /// Allows `cfg(target_has_atomic_equal_alignment = "...")`. |
| (unstable, cfg_target_has_atomic_equal_alignment, "1.60.0", Some(93822)), |
| /// Allows `cfg(target_thread_local)`. |
| (unstable, cfg_target_thread_local, "1.7.0", Some(29594)), |
| /// Allow conditional compilation depending on rust version |
| (unstable, cfg_version, "1.45.0", Some(64796)), |
| /// Allows to use the `#[cfi_encoding = ""]` attribute. |
| (unstable, cfi_encoding, "1.71.0", Some(89653)), |
| /// Allows `for<...>` on closures and coroutines. |
| (unstable, closure_lifetime_binder, "1.64.0", Some(97362)), |
| /// Allows `#[track_caller]` on closures and coroutines. |
| (unstable, closure_track_caller, "1.57.0", Some(87417)), |
| /// Allows to use the `#[cmse_nonsecure_entry]` attribute. |
| (unstable, cmse_nonsecure_entry, "1.48.0", Some(75835)), |
| /// Allows use of the `#[collapse_debuginfo]` attribute. |
| (unstable, collapse_debuginfo, "1.65.0", Some(100758)), |
| /// Allows `async {}` expressions in const contexts. |
| (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 basic arithmetic on floating point types in a `const fn`. |
| (unstable, const_fn_floating_point_arithmetic, "1.48.0", Some(57241)), |
| /// Allows `for _ in _` loops in const contexts. |
| (unstable, const_for, "1.56.0", Some(87575)), |
| /// Allows using `&mut` in constant functions. |
| (unstable, const_mut_refs, "1.41.0", Some(57349)), |
| /// Be more precise when looking for live drops in a const context. |
| (unstable, const_precise_live_drops, "1.46.0", Some(73255)), |
| /// Allows references to types with interior mutability within constants |
| (unstable, const_refs_to_cell, "1.51.0", Some(80384)), |
| /// Allows `impl const Trait for T` syntax. |
| (unstable, const_trait_impl, "1.42.0", Some(67792)), |
| /// Allows the `?` operator in const contexts. |
| (unstable, const_try, "1.56.0", Some(74935)), |
| /// Allows coroutines to be cloned. |
| (unstable, coroutine_clone, "1.65.0", Some(95360)), |
| /// Allows defining coroutines. |
| (unstable, coroutines, "1.21.0", Some(43122)), |
| /// Allows function attribute `#[coverage(on/off)]`, to control coverage |
| /// instrumentation of that function. |
| (unstable, coverage_attribute, "1.74.0", Some(84605)), |
| /// Allows users to provide classes for fenced code block using `class:classname`. |
| (unstable, custom_code_classes_in_docs, "1.74.0", Some(79483)), |
| /// Allows non-builtin attributes in inner attribute position. |
| (unstable, custom_inner_attributes, "1.30.0", Some(54726)), |
| /// Allows custom test frameworks with `#![test_runner]` and `#[test_case]`. |
| (unstable, custom_test_frameworks, "1.30.0", Some(50297)), |
| /// Allows declarative macros 2.0 (`macro`). |
| (unstable, decl_macro, "1.17.0", Some(39412)), |
| /// Allows default type parameters to influence type inference. |
| (unstable, default_type_parameter_fallback, "1.3.0", Some(27336)), |
| /// Allows using `#[deprecated_safe]` to deprecate the safeness of a function or trait |
| (unstable, deprecated_safe, "1.61.0", Some(94978)), |
| /// Allows having using `suggestion` in the `#[deprecated]` attribute. |
| (unstable, deprecated_suggestion, "1.61.0", Some(94785)), |
| /// Allows using the `#[diagnostic]` attribute tool namespace |
| (unstable, diagnostic_namespace, "1.73.0", Some(111996)), |
| /// Controls errors in trait implementations. |
| (unstable, do_not_recommend, "1.67.0", Some(51992)), |
| /// Tells rustdoc to automatically generate `#[doc(cfg(...))]`. |
| (unstable, doc_auto_cfg, "1.58.0", Some(43781)), |
| /// Allows `#[doc(cfg(...))]`. |
| (unstable, doc_cfg, "1.21.0", Some(43781)), |
| /// Allows `#[doc(cfg_hide(...))]`. |
| (unstable, doc_cfg_hide, "1.57.0", Some(43781)), |
| /// Allows `#[doc(masked)]`. |
| (unstable, doc_masked, "1.21.0", Some(44027)), |
| /// Allows `dyn* Trait` objects. |
| (incomplete, dyn_star, "1.65.0", Some(102425)), |
| /// Uses generic effect parameters for ~const bounds |
| (unstable, effects, "1.72.0", Some(102090)), |
| /// Allows `X..Y` patterns. |
| (unstable, exclusive_range_pattern, "1.11.0", Some(37854)), |
| /// Allows exhaustive pattern matching on types that contain uninhabited types. |
| (unstable, exhaustive_patterns, "1.13.0", Some(51085)), |
| /// Allows explicit tail calls via `become` expression. |
| (incomplete, explicit_tail_calls, "1.72.0", Some(112788)), |
| /// Allows using `efiapi`, `sysv64` and `win64` as calling convention |
| /// for functions with varargs. |
| (unstable, extended_varargs_abi_support, "1.65.0", Some(100189)), |
| /// Allows defining `extern type`s. |
| (unstable, extern_types, "1.23.0", Some(43467)), |
| /// Allows the use of `#[ffi_const]` on foreign functions. |
| (unstable, ffi_const, "1.45.0", Some(58328)), |
| /// Allows the use of `#[ffi_pure]` on foreign functions. |
| (unstable, ffi_pure, "1.45.0", Some(58329)), |
| /// Allows using `#[ffi_returns_twice]` on foreign functions. |
| (unstable, ffi_returns_twice, "1.34.0", Some(58314)), |
| /// Allows using `#[repr(align(...))]` on function items |
| (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 defining gen blocks and `gen fn`. |
| (unstable, gen_blocks, "1.75.0", Some(117078)), |
| /// Infer generic args for both consts and types. |
| (unstable, generic_arg_infer, "1.55.0", Some(85077)), |
| /// An extension to the `generic_associated_types` feature, allowing incomplete features. |
| (incomplete, generic_associated_types_extended, "1.61.0", Some(95451)), |
| /// Allows non-trivial generic constants which have to have wfness manually propagated to callers |
| (incomplete, generic_const_exprs, "1.56.0", Some(76560)), |
| /// Allows generic parameters and where-clauses on free & associated const items. |
| (incomplete, generic_const_items, "1.73.0", Some(113521)), |
| /// Allows using `..=X` as a patterns in slices. |
| (unstable, half_open_range_patterns_in_slices, "1.66.0", Some(67264)), |
| /// Allows `if let` guard in match arms. |
| (unstable, if_let_guard, "1.47.0", Some(51114)), |
| /// Allows `impl Trait` to be used inside associated types (RFC 2515). |
| (unstable, impl_trait_in_assoc_type, "1.70.0", Some(63063)), |
| /// Allows `impl Trait` as output type in `Fn` traits in return position of functions. |
| (unstable, impl_trait_in_fn_trait_return, "1.64.0", Some(99697)), |
| /// Allows using imported `main` function |
| (unstable, imported_main, "1.53.0", Some(28937)), |
| /// Allows associated types in inherent impls. |
| (incomplete, inherent_associated_types, "1.52.0", Some(8995)), |
| /// Allow anonymous constants from an inline `const` block |
| (unstable, inline_const, "1.49.0", Some(76001)), |
| /// Allow anonymous constants from an inline `const` block in pattern position |
| (incomplete, inline_const_pat, "1.58.0", Some(76001)), |
| /// Allows using `pointer` and `reference` in intra-doc links |
| (unstable, intra_doc_pointers, "1.51.0", Some(80896)), |
| // Allows setting the threshold for the `large_assignments` lint. |
| (unstable, large_assignments, "1.52.0", Some(83518)), |
| /// Allow to have type alias types for inter-crate use. |
| (incomplete, lazy_type_alias, "1.72.0", Some(112792)), |
| /// Allows `if/while p && let q = r && ...` chains. |
| (unstable, let_chains, "1.37.0", Some(53667)), |
| /// Allows using `#[link(kind = "link-arg", name = "...")]` |
| /// to pass custom arguments to the linker. |
| (unstable, link_arg_attribute, "1.76.0", Some(99427)), |
| /// Allows using `reason` in lint attributes and the `#[expect(lint)]` lint check. |
| (unstable, lint_reasons, "1.31.0", Some(54503)), |
| /// Give access to additional metadata about declarative macro meta-variables. |
| (unstable, macro_metavar_expr, "1.61.0", Some(83527)), |
| /// Allows `#[marker]` on certain traits allowing overlapping implementations. |
| (unstable, marker_trait_attr, "1.30.0", Some(29864)), |
| /// Allows exhaustive pattern matching on types that contain uninhabited types in cases that are |
| /// unambiguously sound. |
| (incomplete, min_exhaustive_patterns, "1.77.0", Some(119612)), |
| /// A minimal, sound subset of specialization intended to be used by the |
| /// standard library until the soundness issues with specialization |
| /// are fixed. |
| (unstable, min_specialization, "1.7.0", Some(31844)), |
| /// Allows qualified paths in struct expressions, struct patterns and tuple struct patterns. |
| (unstable, more_qualified_paths, "1.54.0", Some(86935)), |
| /// Allows the `#[must_not_suspend]` attribute. |
| (unstable, must_not_suspend, "1.57.0", Some(83310)), |
| /// Allows using `#[naked]` on functions. |
| (unstable, naked_functions, "1.9.0", Some(90957)), |
| /// Allows specifying the as-needed link modifier |
| (unstable, native_link_modifiers_as_needed, "1.53.0", Some(81490)), |
| /// Allow negative trait implementations. |
| (unstable, negative_impls, "1.44.0", Some(68318)), |
| /// Allows the `!` pattern. |
| (incomplete, never_patterns, "1.76.0", Some(118155)), |
| /// Allows the `!` type. Does not imply 'exhaustive_patterns' (below) any more. |
| (unstable, never_type, "1.13.0", Some(35121)), |
| /// Allows diverging expressions to fall back to `!` rather than `()`. |
| (unstable, never_type_fallback, "1.41.0", Some(65992)), |
| /// Allows `#![no_core]`. |
| (unstable, no_core, "1.3.0", Some(29639)), |
| /// Allows the use of `no_sanitize` attribute. |
| (unstable, no_sanitize, "1.42.0", Some(39699)), |
| /// Allows using the `non_exhaustive_omitted_patterns` lint. |
| (unstable, non_exhaustive_omitted_patterns_lint, "1.57.0", Some(89554)), |
| /// Allows `for<T>` binders in where-clauses |
| (incomplete, non_lifetime_binders, "1.69.0", Some(108185)), |
| /// Allows making `dyn Trait` well-formed even if `Trait` is not object safe. |
| /// In that case, `dyn Trait: Trait` does not hold. Moreover, coercions and |
| /// casts in safe Rust to `dyn Trait` for such a `Trait` is also forbidden. |
| (unstable, object_safe_for_dispatch, "1.40.0", Some(43561)), |
| /// Allows using enums in offset_of! |
| (unstable, offset_of_enum, "1.75.0", Some(120141)), |
| /// Allows using multiple nested field accesses in offset_of! |
| (unstable, offset_of_nested, "1.77.0", Some(120140)), |
| /// Allows using `#[optimize(X)]`. |
| (unstable, optimize_attribute, "1.34.0", Some(54882)), |
| /// Allows macro attributes on expressions, statements and non-inline modules. |
| (unstable, proc_macro_hygiene, "1.30.0", Some(54727)), |
| /// Allows `&raw const $place_expr` and `&raw mut $place_expr` expressions. |
| (unstable, raw_ref_op, "1.41.0", Some(64490)), |
| /// Allows using the `#[register_tool]` attribute. |
| (unstable, register_tool, "1.41.0", Some(66079)), |
| /// Allows the `#[repr(i128)]` attribute for enums. |
| (incomplete, repr128, "1.16.0", Some(56071)), |
| /// Allows `repr(simd)` and importing the various simd intrinsics. |
| (unstable, repr_simd, "1.4.0", Some(27731)), |
| /// Allows bounding the return type of AFIT/RPITIT. |
| (incomplete, return_type_notation, "1.70.0", Some(109417)), |
| /// Allows `extern "rust-cold"`. |
| (unstable, rust_cold_cc, "1.63.0", Some(97544)), |
| /// Allows the use of SIMD types in functions declared in `extern` blocks. |
| (unstable, simd_ffi, "1.0.0", Some(27731)), |
| /// Allows specialization of implementations (RFC 1210). |
| (incomplete, specialization, "1.7.0", Some(31844)), |
| /// Allows attributes on expressions and non-item statements. |
| (unstable, stmt_expr_attributes, "1.6.0", Some(15701)), |
| /// Allows lints part of the strict provenance effort. |
| (unstable, strict_provenance, "1.61.0", Some(95228)), |
| /// Allows string patterns to dereference values to match them. |
| (unstable, string_deref_patterns, "1.67.0", Some(87121)), |
| /// Allows the use of `#[target_feature]` on safe functions. |
| (unstable, target_feature_11, "1.45.0", Some(69098)), |
| /// Allows using `#[thread_local]` on `static` items. |
| (unstable, thread_local, "1.0.0", Some(29594)), |
| /// Allows defining `trait X = A + B;` alias items. |
| (unstable, trait_alias, "1.24.0", Some(41517)), |
| /// Allows dyn upcasting trait objects via supertraits. |
| /// Dyn upcasting is casting, e.g., `dyn Foo -> dyn Bar` where `Foo: Bar`. |
| (unstable, trait_upcasting, "1.56.0", Some(65991)), |
| /// Allows for transmuting between arrays with sizes that contain generic consts. |
| (unstable, transmute_generic_consts, "1.70.0", Some(109929)), |
| /// Allows #[repr(transparent)] on unions (RFC 2645). |
| (unstable, transparent_unions, "1.37.0", Some(60405)), |
| /// Allows inconsistent bounds in where clauses. |
| (unstable, trivial_bounds, "1.28.0", Some(48214)), |
| /// Allows using `try {...}` expressions. |
| (unstable, try_blocks, "1.29.0", Some(31436)), |
| /// Allows `impl Trait` to be used inside type aliases (RFC 2515). |
| (unstable, type_alias_impl_trait, "1.38.0", Some(63063)), |
| /// Allows the use of type ascription in expressions. |
| (unstable, type_ascription, "1.6.0", Some(23416)), |
| /// Allows creation of instances of a struct by moving fields that have |
| /// not changed from prior instances of the same struct (RFC #2528) |
| (unstable, type_changing_struct_update, "1.58.0", Some(86555)), |
| /// Allows using type privacy lints (`private_interfaces`, `private_bounds`, `unnameable_types`). |
| (unstable, type_privacy_lints, "1.72.0", Some(48054)), |
| /// Enables rustc to generate code that instructs libstd to NOT ignore SIGPIPE. |
| (unstable, unix_sigpipe, "1.65.0", Some(97889)), |
| /// Allows unnamed fields of struct and union type |
| (incomplete, unnamed_fields, "1.74.0", Some(49804)), |
| /// Allows unsized fn parameters. |
| (unstable, unsized_fn_params, "1.49.0", Some(48055)), |
| /// Allows unsized rvalues at arguments and parameters. |
| (incomplete, unsized_locals, "1.30.0", Some(48055)), |
| /// Allows unsized tuple coercion. |
| (unstable, unsized_tuple_coercion, "1.20.0", Some(42877)), |
| /// Allows using the `#[used(linker)]` (or `#[used(compiler)]`) attribute. |
| (unstable, used_with_arg, "1.60.0", Some(93798)), |
| /// Allows `extern "wasm" fn` |
| (unstable, wasm_abi, "1.53.0", Some(83788)), |
| /// Allows `do yeet` expressions |
| (unstable, yeet_expr, "1.62.0", Some(96373)), |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| // Features are listed in alphabetical order. Tidy will fail if you don't keep it this way. |
| // !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-end: actual feature gates |
| // ------------------------------------------------------------------------- |
| ); |
| |
| /// Some features are not allowed to be used together at the same time, if |
| /// the two are present, produce an error. |
| /// |
| /// Currently empty, but we will probably need this again in the future, |
| /// so let's keep it in for now. |
| pub const INCOMPATIBLE_FEATURES: &[(Symbol, Symbol)] = &[]; |
