| //! List of the active feature gates. |
| |
| use super::{State, Feature}; |
| |
| use crate::edition::Edition; |
| use crate::symbol::{Symbol, sym}; |
| |
| use syntax_pos::Span; |
| |
| macro_rules! set { |
| ($field: ident) => {{ |
| fn f(features: &mut Features, _: Span) { |
| features.$field = true; |
| } |
| f as fn(&mut Features, Span) |
| }} |
| } |
| |
| macro_rules! declare_features { |
| ($( |
| $(#[doc = $doc:tt])* (active, $feature:ident, $ver:expr, $issue:expr, $edition:expr), |
| )+) => { |
| /// Represents active features that are currently being implemented or |
| /// currently being considered for addition/removal. |
| pub const ACTIVE_FEATURES: |
| &[Feature] = |
| &[$( |
| // (sym::$feature, $ver, $issue, $edition, set!($feature)) |
| Feature { |
| state: State::Active { set: set!($feature) }, |
| name: sym::$feature, |
| since: $ver, |
| issue: $issue, |
| edition: $edition, |
| description: concat!($($doc,)*), |
| } |
| ),+]; |
| |
| /// A set of features to be used by later passes. |
| #[derive(Clone)] |
| pub struct Features { |
| /// `#![feature]` attrs for language features, for error reporting. |
| pub declared_lang_features: Vec<(Symbol, Span, Option<Symbol>)>, |
| /// `#![feature]` attrs for non-language (library) features. |
| pub declared_lib_features: Vec<(Symbol, Span)>, |
| $( |
| $(#[doc = $doc])* |
| pub $feature: bool |
| ),+ |
| } |
| |
| impl Features { |
| pub fn new() -> Features { |
| Features { |
| declared_lang_features: Vec::new(), |
| declared_lib_features: Vec::new(), |
| $($feature: false),+ |
| } |
| } |
| |
| pub fn walk_feature_fields<F>(&self, mut f: F) |
| where F: FnMut(&str, bool) |
| { |
| $(f(stringify!($feature), self.$feature);)+ |
| } |
| } |
| }; |
| } |
| |
| impl Feature { |
| /// Sets this feature in `Features`. Panics if called on a non-active feature. |
| pub fn set(&self, features: &mut Features, span: Span) { |
| match self.state { |
| State::Active { set } => set(features, span), |
| _ => panic!("called `set` on feature `{}` which is not `active`", self.name) |
| } |
| } |
| } |
| |
| // If you change this, please modify `src/doc/unstable-book` as well. |
| // |
| // Don't ever remove anything from this list; move them to `removed.rs`. |
| // |
| // The version numbers here correspond to the version in which the current status |
| // was set. This is most important for knowing when a particular feature became |
| // stable (active). |
| // |
| // Note that the features are grouped into internal/user-facing and then |
| // sorted by version 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. |
| |
| declare_features! ( |
| // ------------------------------------------------------------------------- |
| // feature-group-start: internal feature gates |
| // ------------------------------------------------------------------------- |
| |
| // no-tracking-issue-start |
| |
| /// Allows using compiler's own crates. |
| (active, rustc_private, "1.0.0", Some(27812), None), |
| |
| /// Allows using the `rust-intrinsic`'s "ABI". |
| (active, intrinsics, "1.0.0", None, None), |
| |
| /// Allows using `#[lang = ".."]` attribute for linking items to special compiler logic. |
| (active, lang_items, "1.0.0", None, None), |
| |
| /// Allows using the `#[stable]` and `#[unstable]` attributes. |
| (active, staged_api, "1.0.0", None, 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). |
| (active, allow_internal_unstable, "1.0.0", None, 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). |
| (active, allow_internal_unsafe, "1.0.0", None, None), |
| |
| /// Allows using `#[rustc_const_unstable(feature = "foo", ..)]` which |
| /// lets a function to be `const` when opted into with `#![feature(foo)]`. |
| (active, rustc_const_unstable, "1.0.0", None, None), |
| |
| /// no-tracking-issue-end |
| |
| /// Allows using `#[link_name="llvm.*"]`. |
| (active, link_llvm_intrinsics, "1.0.0", Some(29602), None), |
| |
| /// Allows using `rustc_*` attributes (RFC 572). |
| (active, rustc_attrs, "1.0.0", Some(29642), None), |
| |
| /// Allows using `#[on_unimplemented(..)]` on traits. |
| (active, on_unimplemented, "1.0.0", Some(29628), None), |
| |
| /// Allows using the `box $expr` syntax. |
| (active, box_syntax, "1.0.0", Some(49733), None), |
| |
| /// Allows using `#[main]` to replace the entrypoint `#[lang = "start"]` calls. |
| (active, main, "1.0.0", Some(29634), None), |
| |
| /// Allows using `#[start]` on a function indicating that it is the program entrypoint. |
| (active, start, "1.0.0", Some(29633), None), |
| |
| /// Allows using the `#[fundamental]` attribute. |
| (active, fundamental, "1.0.0", Some(29635), None), |
| |
| /// Allows using the `rust-call` ABI. |
| (active, unboxed_closures, "1.0.0", Some(29625), None), |
| |
| /// Allows using the `#[linkage = ".."]` attribute. |
| (active, linkage, "1.0.0", Some(29603), None), |
| |
| /// Allows features specific to OIBIT (auto traits). |
| (active, optin_builtin_traits, "1.0.0", Some(13231), None), |
| |
| /// Allows using `box` in patterns (RFC 469). |
| (active, box_patterns, "1.0.0", Some(29641), None), |
| |
| // no-tracking-issue-start |
| |
| /// Allows using `#[prelude_import]` on glob `use` items. |
| (active, prelude_import, "1.2.0", None, None), |
| |
| // no-tracking-issue-end |
| |
| // no-tracking-issue-start |
| |
| /// Allows using `#[omit_gdb_pretty_printer_section]`. |
| (active, omit_gdb_pretty_printer_section, "1.5.0", None, None), |
| |
| /// Allows using the `vectorcall` ABI. |
| (active, abi_vectorcall, "1.7.0", None, None), |
| |
| // no-tracking-issue-end |
| |
| /// Allows using `#[structural_match]` which indicates that a type is structurally matchable. |
| (active, structural_match, "1.8.0", Some(31434), None), |
| |
| /// Allows using the `may_dangle` attribute (RFC 1327). |
| (active, dropck_eyepatch, "1.10.0", Some(34761), None), |
| |
| /// Allows using the `#![panic_runtime]` attribute. |
| (active, panic_runtime, "1.10.0", Some(32837), None), |
| |
| /// Allows declaring with `#![needs_panic_runtime]` that a panic runtime is needed. |
| (active, needs_panic_runtime, "1.10.0", Some(32837), None), |
| |
| // no-tracking-issue-start |
| |
| /// Allows identifying the `compiler_builtins` crate. |
| (active, compiler_builtins, "1.13.0", None, None), |
| |
| /// Allows using the `unadjusted` ABI; perma-unstable. |
| (active, abi_unadjusted, "1.16.0", None, None), |
| |
| /// Allows identifying crates that contain sanitizer runtimes. |
| (active, sanitizer_runtime, "1.17.0", None, None), |
| |
| /// Used to identify crates that contain the profiler runtime. |
| (active, profiler_runtime, "1.18.0", None, None), |
| |
| /// Allows using the `thiscall` ABI. |
| (active, abi_thiscall, "1.19.0", None, None), |
| |
| /// Allows using `#![needs_allocator]`, an implementation detail of `#[global_allocator]`. |
| (active, allocator_internals, "1.20.0", None, None), |
| |
| // no-tracking-issue-end |
| |
| /// Added for testing E0705; perma-unstable. |
| (active, test_2018_feature, "1.31.0", Some(0), Some(Edition::Edition2018)), |
| |
| // ------------------------------------------------------------------------- |
| // 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. |
| (active, arm_target_feature, "1.27.0", Some(44839), None), |
| (active, aarch64_target_feature, "1.27.0", Some(44839), None), |
| (active, hexagon_target_feature, "1.27.0", Some(44839), None), |
| (active, powerpc_target_feature, "1.27.0", Some(44839), None), |
| (active, mips_target_feature, "1.27.0", Some(44839), None), |
| (active, avx512_target_feature, "1.27.0", Some(44839), None), |
| (active, mmx_target_feature, "1.27.0", Some(44839), None), |
| (active, sse4a_target_feature, "1.27.0", Some(44839), None), |
| (active, tbm_target_feature, "1.27.0", Some(44839), None), |
| (active, wasm_target_feature, "1.30.0", Some(44839), None), |
| (active, adx_target_feature, "1.32.0", Some(44839), None), |
| (active, cmpxchg16b_target_feature, "1.32.0", Some(44839), None), |
| (active, movbe_target_feature, "1.34.0", Some(44839), None), |
| (active, rtm_target_feature, "1.35.0", Some(44839), None), |
| (active, f16c_target_feature, "1.36.0", Some(44839), None), |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-end: actual feature gates (target features) |
| // ------------------------------------------------------------------------- |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-start: actual feature gates |
| // ------------------------------------------------------------------------- |
| |
| /// Allows using the `#[link_args]` attribute. |
| (active, link_args, "1.0.0", Some(29596), None), |
| |
| /// Allows defining identifiers beyond ASCII. |
| (active, non_ascii_idents, "1.0.0", Some(55467), None), |
| |
| /// Allows using `#[plugin_registrar]` on functions. |
| (active, plugin_registrar, "1.0.0", Some(29597), None), |
| |
| /// Allows using `#![plugin(myplugin)]`. |
| (active, plugin, "1.0.0", Some(29597), None), |
| |
| /// Allows using `#[thread_local]` on `static` items. |
| (active, thread_local, "1.0.0", Some(29594), None), |
| |
| /// Allows the use of SIMD types in functions declared in `extern` blocks. |
| (active, simd_ffi, "1.0.0", Some(27731), None), |
| |
| /// Allows using custom attributes (RFC 572). |
| (active, custom_attribute, "1.0.0", Some(29642), None), |
| |
| /// Allows using non lexical lifetimes (RFC 2094). |
| (active, nll, "1.0.0", Some(43234), None), |
| |
| /// Allows using slice patterns. |
| (active, slice_patterns, "1.0.0", Some(62254), None), |
| |
| /// Allows the definition of `const` functions with some advanced features. |
| (active, const_fn, "1.2.0", Some(57563), None), |
| |
| /// Allows associated type defaults. |
| (active, associated_type_defaults, "1.2.0", Some(29661), None), |
| |
| /// Allows `#![no_core]`. |
| (active, no_core, "1.3.0", Some(29639), None), |
| |
| /// Allows default type parameters to influence type inference. |
| (active, default_type_parameter_fallback, "1.3.0", Some(27336), None), |
| |
| /// Allows `repr(simd)` and importing the various simd intrinsics. |
| (active, repr_simd, "1.4.0", Some(27731), None), |
| |
| /// Allows `extern "platform-intrinsic" { ... }`. |
| (active, platform_intrinsics, "1.4.0", Some(27731), None), |
| |
| /// Allows `#[unwind(..)]`. |
| /// |
| /// Permits specifying whether a function should permit unwinding or abort on unwind. |
| (active, unwind_attributes, "1.4.0", Some(58760), None), |
| |
| /// Allows `#[no_debug]`. |
| (active, no_debug, "1.5.0", Some(29721), None), |
| |
| /// Allows attributes on expressions and non-item statements. |
| (active, stmt_expr_attributes, "1.6.0", Some(15701), None), |
| |
| /// Allows the use of type ascription in expressions. |
| (active, type_ascription, "1.6.0", Some(23416), None), |
| |
| /// Allows `cfg(target_thread_local)`. |
| (active, cfg_target_thread_local, "1.7.0", Some(29594), None), |
| |
| /// Allows specialization of implementations (RFC 1210). |
| (active, specialization, "1.7.0", Some(31844), None), |
| |
| /// Allows using `#[naked]` on functions. |
| (active, naked_functions, "1.9.0", Some(32408), None), |
| |
| /// Allows `cfg(target_has_atomic = "...")`. |
| (active, cfg_target_has_atomic, "1.9.0", Some(32976), None), |
| |
| /// Allows `X..Y` patterns. |
| (active, exclusive_range_pattern, "1.11.0", Some(37854), None), |
| |
| /// Allows the `!` type. Does not imply 'exhaustive_patterns' (below) any more. |
| (active, never_type, "1.13.0", Some(35121), None), |
| |
| /// Allows exhaustive pattern matching on types that contain uninhabited types. |
| (active, exhaustive_patterns, "1.13.0", Some(51085), None), |
| |
| /// Allows untagged unions `union U { ... }`. |
| (active, untagged_unions, "1.13.0", Some(32836), None), |
| |
| /// Allows `#[link(..., cfg(..))]`. |
| (active, link_cfg, "1.14.0", Some(37406), None), |
| |
| /// Allows `extern "ptx-*" fn()`. |
| (active, abi_ptx, "1.15.0", Some(38788), None), |
| |
| /// Allows the `#[repr(i128)]` attribute for enums. |
| (active, repr128, "1.16.0", Some(35118), None), |
| |
| /// Allows `#[link(kind="static-nobundle"...)]`. |
| (active, static_nobundle, "1.16.0", Some(37403), None), |
| |
| /// Allows `extern "msp430-interrupt" fn()`. |
| (active, abi_msp430_interrupt, "1.16.0", Some(38487), None), |
| |
| /// Allows declarative macros 2.0 (`macro`). |
| (active, decl_macro, "1.17.0", Some(39412), None), |
| |
| /// Allows `extern "x86-interrupt" fn()`. |
| (active, abi_x86_interrupt, "1.17.0", Some(40180), None), |
| |
| /// Allows overlapping impls of marker traits. |
| (active, overlapping_marker_traits, "1.18.0", Some(29864), None), |
| |
| /// Allows a test to fail without failing the whole suite. |
| (active, allow_fail, "1.19.0", Some(46488), None), |
| |
| /// Allows unsized tuple coercion. |
| (active, unsized_tuple_coercion, "1.20.0", Some(42877), None), |
| |
| /// Allows defining generators. |
| (active, generators, "1.21.0", Some(43122), None), |
| |
| /// Allows `#[doc(cfg(...))]`. |
| (active, doc_cfg, "1.21.0", Some(43781), None), |
| |
| /// Allows `#[doc(masked)]`. |
| (active, doc_masked, "1.21.0", Some(44027), None), |
| |
| /// Allows `#[doc(spotlight)]`. |
| (active, doc_spotlight, "1.22.0", Some(45040), None), |
| |
| /// Allows `#[doc(include = "some-file")]`. |
| (active, external_doc, "1.22.0", Some(44732), None), |
| |
| /// Allows future-proofing enums/structs with the `#[non_exhaustive]` attribute (RFC 2008). |
| (active, non_exhaustive, "1.22.0", Some(44109), None), |
| |
| /// Allows using `crate` as visibility modifier, synonymous with `pub(crate)`. |
| (active, crate_visibility_modifier, "1.23.0", Some(53120), None), |
| |
| /// Allows defining `extern type`s. |
| (active, extern_types, "1.23.0", Some(43467), None), |
| |
| /// Allows trait methods with arbitrary self types. |
| (active, arbitrary_self_types, "1.23.0", Some(44874), None), |
| |
| /// Allows in-band quantification of lifetime bindings (e.g., `fn foo(x: &'a u8) -> &'a u8`). |
| (active, in_band_lifetimes, "1.23.0", Some(44524), None), |
| |
| /// Allows associated types to be generic, e.g., `type Foo<T>;` (RFC 1598). |
| (active, generic_associated_types, "1.23.0", Some(44265), None), |
| |
| /// Allows defining `trait X = A + B;` alias items. |
| (active, trait_alias, "1.24.0", Some(41517), None), |
| |
| /// Allows infering `'static` outlives requirements (RFC 2093). |
| (active, infer_static_outlives_requirements, "1.26.0", Some(54185), None), |
| |
| /// Allows accessing fields of unions inside `const` functions. |
| (active, const_fn_union, "1.27.0", Some(51909), None), |
| |
| /// Allows casting raw pointers to `usize` during const eval. |
| (active, const_raw_ptr_to_usize_cast, "1.27.0", Some(51910), None), |
| |
| /// Allows dereferencing raw pointers during const eval. |
| (active, const_raw_ptr_deref, "1.27.0", Some(51911), None), |
| |
| /// Allows comparing raw pointers during const eval. |
| (active, const_compare_raw_pointers, "1.27.0", Some(53020), None), |
| |
| /// Allows `#[doc(alias = "...")]`. |
| (active, doc_alias, "1.27.0", Some(50146), None), |
| |
| /// Allows inconsistent bounds in where clauses. |
| (active, trivial_bounds, "1.28.0", Some(48214), None), |
| |
| /// Allows `'a: { break 'a; }`. |
| (active, label_break_value, "1.28.0", Some(48594), None), |
| |
| /// Allows using `#[doc(keyword = "...")]`. |
| (active, doc_keyword, "1.28.0", Some(51315), None), |
| |
| /// Allows reinterpretation of the bits of a value of one type as another |
| /// type during const eval. |
| (active, const_transmute, "1.29.0", Some(53605), None), |
| |
| /// Allows using `try {...}` expressions. |
| (active, try_blocks, "1.29.0", Some(31436), None), |
| |
| /// Allows defining an `#[alloc_error_handler]`. |
| (active, alloc_error_handler, "1.29.0", Some(51540), None), |
| |
| /// Allows using the `amdgpu-kernel` ABI. |
| (active, abi_amdgpu_kernel, "1.29.0", Some(51575), None), |
| |
| /// Allows panicking during const eval (producing compile-time errors). |
| (active, const_panic, "1.30.0", Some(51999), None), |
| |
| /// Allows `#[marker]` on certain traits allowing overlapping implementations. |
| (active, marker_trait_attr, "1.30.0", Some(29864), None), |
| |
| /// Allows macro invocations on modules expressions and statements and |
| /// procedural macros to expand to non-items. |
| (active, proc_macro_hygiene, "1.30.0", Some(54727), None), |
| |
| /// Allows unsized rvalues at arguments and parameters. |
| (active, unsized_locals, "1.30.0", Some(48055), None), |
| |
| /// Allows custom test frameworks with `#![test_runner]` and `#[test_case]`. |
| (active, custom_test_frameworks, "1.30.0", Some(50297), None), |
| |
| /// Allows non-builtin attributes in inner attribute position. |
| (active, custom_inner_attributes, "1.30.0", Some(54726), None), |
| |
| /// Allows `impl Trait` in bindings (`let`, `const`, `static`). |
| (active, impl_trait_in_bindings, "1.30.0", Some(63065), None), |
| |
| /// Allows using `reason` in lint attributes and the `#[expect(lint)]` lint check. |
| (active, lint_reasons, "1.31.0", Some(54503), None), |
| |
| /// Allows exhaustive integer pattern matching on `usize` and `isize`. |
| (active, precise_pointer_size_matching, "1.32.0", Some(56354), None), |
| |
| /// Allows relaxing the coherence rules such that |
| /// `impl<T> ForeignTrait<LocalType> for ForeignType<T>` is permitted. |
| (active, re_rebalance_coherence, "1.32.0", Some(55437), None), |
| |
| /// Allows using `#[ffi_returns_twice]` on foreign functions. |
| (active, ffi_returns_twice, "1.34.0", Some(58314), None), |
| |
| /// Allows const generic types (e.g. `struct Foo<const N: usize>(...);`). |
| (active, const_generics, "1.34.0", Some(44580), None), |
| |
| /// Allows using `#[optimize(X)]`. |
| (active, optimize_attribute, "1.34.0", Some(54882), None), |
| |
| /// Allows using C-variadics. |
| (active, c_variadic, "1.34.0", Some(44930), None), |
| |
| /// Allows the user of associated type bounds. |
| (active, associated_type_bounds, "1.34.0", Some(52662), None), |
| |
| /// Allows calling constructor functions in `const fn`. |
| (active, const_constructor, "1.37.0", Some(61456), None), |
| |
| /// Allows `if/while p && let q = r && ...` chains. |
| (active, let_chains, "1.37.0", Some(53667), None), |
| |
| /// Allows #[repr(transparent)] on enums (RFC 2645). |
| (active, transparent_enums, "1.37.0", Some(60405), None), |
| |
| /// Allows #[repr(transparent)] on unions (RFC 2645). |
| (active, transparent_unions, "1.37.0", Some(60405), None), |
| |
| /// Allows explicit discriminants on non-unit enum variants. |
| (active, arbitrary_enum_discriminant, "1.37.0", Some(60553), None), |
| |
| /// Allows `impl Trait` with multiple unrelated lifetimes. |
| (active, member_constraints, "1.37.0", Some(61977), None), |
| |
| /// Allows `async || body` closures. |
| (active, async_closure, "1.37.0", Some(62290), None), |
| |
| /// Allows the use of `#[cfg(doctest)]`; set when rustdoc is collecting doctests. |
| (active, cfg_doctest, "1.37.0", Some(62210), None), |
| |
| /// Allows `[x; N]` where `x` is a constant (RFC 2203). |
| (active, const_in_array_repeat_expressions, "1.37.0", Some(49147), None), |
| |
| /// Allows `impl Trait` to be used inside type aliases (RFC 2515). |
| (active, type_alias_impl_trait, "1.38.0", Some(63063), None), |
| |
| /// Allows the use of or-patterns (e.g., `0 | 1`). |
| (active, or_patterns, "1.38.0", Some(54883), None), |
| |
| /// Allows the definition of `const extern fn` and `const unsafe extern fn`. |
| (active, const_extern_fn, "1.40.0", Some(64926), None), |
| |
| // Allows the use of raw-dylibs (RFC 2627). |
| (active, raw_dylib, "1.40.0", Some(58713), None), |
| |
| /// Enable accurate caller location reporting during panic (RFC 2091). |
| (active, track_caller, "1.40.0", Some(47809), None), |
| |
| // ------------------------------------------------------------------------- |
| // feature-group-end: actual feature gates |
| // ------------------------------------------------------------------------- |
| ); |
| |
| /// 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 const INCOMPLETE_FEATURES: &[Symbol] = &[ |
| sym::impl_trait_in_bindings, |
| sym::generic_associated_types, |
| sym::const_generics, |
| sym::or_patterns, |
| sym::let_chains, |
| sym::raw_dylib, |
| sym::track_caller, |
| ]; |