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|
//! List of the removed feature gates.
use super::{to_nonzero, Feature};
use rustc_span::symbol::sym;
pub struct RemovedFeature {
pub feature: Feature,
pub reason: Option<&'static str>,
}
macro_rules! declare_features {
($(
$(#[doc = $doc:tt])* (removed, $feature:ident, $ver:expr, $issue:expr, $reason:expr),
)+) => {
/// Formerly unstable features that have now been removed.
pub const REMOVED_FEATURES: &[RemovedFeature] = &[
$(RemovedFeature {
feature: Feature {
name: sym::$feature,
since: $ver,
issue: to_nonzero($issue),
},
reason: $reason
}),+
];
};
}
#[rustfmt::skip]
declare_features! (
// -------------------------------------------------------------------------
// feature-group-start: removed features
// -------------------------------------------------------------------------
(removed, advanced_slice_patterns, "1.0.0", Some(62254),
Some("merged into `#![feature(slice_patterns)]`")),
(removed, allocator, "1.0.0", None, None),
/// Allows a test to fail without failing the whole suite.
(removed, allow_fail, "1.19.0", Some(46488), Some("removed due to no clear use cases")),
(removed, await_macro, "1.38.0", Some(50547),
Some("subsumed by `.await` syntax")),
/// Allows using the `box $expr` syntax.
(removed, box_syntax, "1.70.0", Some(49733), Some("replaced with `#[rustc_box]`")),
/// Allows capturing disjoint fields in a closure/coroutine (RFC 2229).
(removed, capture_disjoint_fields, "1.49.0", Some(53488), Some("stabilized in Rust 2021")),
/// Allows comparing raw pointers during const eval.
(removed, const_compare_raw_pointers, "1.46.0", Some(53020),
Some("cannot be allowed in const eval in any meaningful way")),
/// Allows limiting the evaluation steps of const expressions
(removed, const_eval_limit, "1.43.0", Some(67217), Some("removed the limit entirely")),
/// Allows non-trivial generic constants which have to be manually propagated upwards.
(removed, const_evaluatable_checked, "1.48.0", Some(76560), Some("renamed to `generic_const_exprs`")),
/// Allows the definition of `const` functions with some advanced features.
(removed, const_fn, "1.54.0", Some(57563),
Some("split into finer-grained feature gates")),
/// Allows const generic types (e.g. `struct Foo<const N: usize>(...);`).
(removed, const_generics, "1.34.0", Some(44580),
Some("removed in favor of `#![feature(adt_const_params)]` and `#![feature(generic_const_exprs)]`")),
/// Allows `[x; N]` where `x` is a constant (RFC 2203).
(removed, const_in_array_repeat_expressions, "1.37.0", Some(49147),
Some("removed due to causing promotable bugs")),
/// Allows casting raw pointers to `usize` during const eval.
(removed, const_raw_ptr_to_usize_cast, "1.55.0", Some(51910),
Some("at compile-time, pointers do not have an integer value, so these casts cannot be properly supported")),
/// Allows `T: ?const Trait` syntax in bounds.
(removed, const_trait_bound_opt_out, "1.42.0", Some(67794),
Some("Removed in favor of `~const` bound in #![feature(const_trait_impl)]")),
/// Allows using `crate` as visibility modifier, synonymous with `pub(crate)`.
(removed, crate_visibility_modifier, "1.63.0", Some(53120), Some("removed in favor of `pub(crate)`")),
/// Allows using custom attributes (RFC 572).
(removed, custom_attribute, "1.0.0", Some(29642),
Some("removed in favor of `#![register_tool]` and `#![register_attr]`")),
/// Allows the use of `#[derive(Anything)]` as sugar for `#[derive_Anything]`.
(removed, custom_derive, "1.32.0", Some(29644),
Some("subsumed by `#[proc_macro_derive]`")),
/// Allows using `#[doc(keyword = "...")]`.
(removed, doc_keyword, "1.28.0", Some(51315),
Some("merged into `#![feature(rustdoc_internals)]`")),
/// Allows using `doc(primitive)` without a future-incompat warning.
(removed, doc_primitive, "1.56.0", Some(88070),
Some("merged into `#![feature(rustdoc_internals)]`")),
/// Allows `#[doc(spotlight)]`.
/// The attribute was renamed to `#[doc(notable_trait)]`
/// and the feature to `doc_notable_trait`.
(removed, doc_spotlight, "1.22.0", Some(45040),
Some("renamed to `doc_notable_trait`")),
/// Allows using `#[unsafe_destructor_blind_to_params]` (RFC 1238).
(removed, dropck_parametricity, "1.38.0", Some(28498), None),
/// Allows defining `existential type`s.
(removed, existential_type, "1.38.0", Some(63063),
Some("removed in favor of `#![feature(type_alias_impl_trait)]`")),
/// Paths of the form: `extern::foo::bar`
(removed, extern_in_paths, "1.33.0", Some(55600),
Some("subsumed by `::foo::bar` paths")),
/// Allows `#[doc(include = "some-file")]`.
(removed, external_doc, "1.54.0", Some(44732),
Some("use #[doc = include_str!(\"filename\")] instead, which handles macro invocations")),
/// Allows generators to be cloned.
(removed, generator_clone, "1.65.0", Some(95360), Some("renamed to `coroutine_clone`")),
/// Allows defining generators.
(removed, generators, "1.21.0", Some(43122), Some("renamed to `coroutines`")),
/// Allows `impl Trait` in bindings (`let`, `const`, `static`).
(removed, impl_trait_in_bindings, "1.55.0", Some(63065),
Some("the implementation was not maintainable, the feature may get reintroduced once the current refactorings are done")),
(removed, import_shadowing, "1.0.0", None, None),
/// Allows in-band quantification of lifetime bindings (e.g., `fn foo(x: &'a u8) -> &'a u8`).
(removed, in_band_lifetimes, "1.23.0", Some(44524),
Some("removed due to unsolved ergonomic questions and added lifetime resolution complexity")),
/// Allows inferring `'static` outlives requirements (RFC 2093).
(removed, infer_static_outlives_requirements, "1.63.0", Some(54185),
Some("removed as it caused some confusion and discussion was inactive for years")),
/// Lazily evaluate constants. This allows constants to depend on type parameters.
(removed, lazy_normalization_consts, "1.46.0", Some(72219), Some("superseded by `generic_const_exprs`")),
/// Allows using the `#[link_args]` attribute.
(removed, link_args, "1.53.0", Some(29596),
Some("removed in favor of using `-C link-arg=ARG` on command line, \
which is available from cargo build scripts with `cargo:rustc-link-arg` now")),
(removed, macro_reexport, "1.0.0", Some(29638),
Some("subsumed by `pub use`")),
/// Allows using `#[main]` to replace the entrypoint `#[lang = "start"]` calls.
(removed, main, "1.53.0", Some(29634), None),
(removed, managed_boxes, "1.0.0", None, None),
/// Allows the use of type alias impl trait in function return positions
(removed, min_type_alias_impl_trait, "1.56.0", Some(63063),
Some("removed in favor of full type_alias_impl_trait")),
(removed, needs_allocator, "1.4.0", Some(27389),
Some("subsumed by `#![feature(allocator_internals)]`")),
/// Allows use of unary negate on unsigned integers, e.g., -e for e: u8
(removed, negate_unsigned, "1.0.0", Some(29645), None),
/// Allows `#[no_coverage]` on functions.
/// The feature was renamed to `coverage_attribute` and the attribute to `#[coverage(on|off)]`
(removed, no_coverage, "1.74.0", Some(84605), Some("renamed to `coverage_attribute`")),
/// Allows `#[no_debug]`.
(removed, no_debug, "1.43.0", Some(29721), Some("removed due to lack of demand")),
/// Note: this feature was previously recorded in a separate
/// `STABLE_REMOVED` list because it, uniquely, was once stable but was
/// then removed. But there was no utility storing it separately, so now
/// it's in this list.
(removed, no_stack_check, "1.0.0", None, None),
/// Allows using `#[on_unimplemented(..)]` on traits.
/// (Moved to `rustc_attrs`.)
(removed, on_unimplemented, "1.40.0", None, None),
/// A way to temporarily opt out of opt-in copy. This will *never* be accepted.
(removed, opt_out_copy, "1.0.0", None, None),
/// Allows features specific to OIBIT (now called auto traits).
/// Renamed to `auto_traits`.
(removed, optin_builtin_traits, "1.0.0", Some(13231),
Some("renamed to `auto_traits`")),
/// Allows overlapping impls of marker traits.
(removed, overlapping_marker_traits, "1.42.0", Some(29864),
Some("removed in favor of `#![feature(marker_trait_attr)]`")),
(removed, panic_implementation, "1.28.0", Some(44489),
Some("subsumed by `#[panic_handler]`")),
/// Allows using `#![plugin(myplugin)]`.
(removed, plugin, "1.75.0", Some(29597),
Some("plugins are no longer supported")),
/// Allows using `#[plugin_registrar]` on functions.
(removed, plugin_registrar, "1.54.0", Some(29597),
Some("plugins are no longer supported")),
/// Allows exhaustive integer pattern matching with `usize::MAX`/`isize::MIN`/`isize::MAX`.
(removed, precise_pointer_size_matching, "1.32.0", Some(56354),
Some("removed in favor of half-open ranges")),
(removed, proc_macro_expr, "1.27.0", Some(54727),
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, proc_macro_gen, "1.27.0", Some(54727),
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, proc_macro_mod, "1.27.0", Some(54727),
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, proc_macro_non_items, "1.27.0", Some(54727),
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, pub_macro_rules, "1.53.0", Some(78855),
Some("removed due to being incomplete, in particular it does not work across crates")),
(removed, pushpop_unsafe, "1.2.0", None, None),
(removed, quad_precision_float, "1.0.0", None, None),
(removed, quote, "1.33.0", Some(29601), None),
(removed, reflect, "1.0.0", Some(27749), None),
/// Allows using the `#[register_attr]` attribute.
(removed, register_attr, "1.65.0", Some(66080),
Some("removed in favor of `#![register_tool]`")),
(removed, rust_2018_preview, "1.76.0", None,
Some("2018 Edition preview is no longer relevant")),
/// Allows using the macros:
/// + `__diagnostic_used`
/// + `__register_diagnostic`
/// +`__build_diagnostic_array`
(removed, rustc_diagnostic_macros, "1.38.0", None, None),
/// Allows identifying crates that contain sanitizer runtimes.
(removed, sanitizer_runtime, "1.17.0", None, None),
(removed, simd, "1.0.0", Some(27731),
Some("removed in favor of `#[repr(simd)]`")),
/// Allows `#[link(kind = "static-nobundle", ...)]`.
(removed, static_nobundle, "1.16.0", Some(37403),
Some(r#"subsumed by `#[link(kind = "static", modifiers = "-bundle", ...)]`"#)),
(removed, struct_inherit, "1.0.0", None, None),
(removed, test_removed_feature, "1.0.0", None, None),
/// Allows using items which are missing stability attributes
(removed, unmarked_api, "1.0.0", None, None),
(removed, unsafe_no_drop_flag, "1.0.0", None, None),
/// Allows `union` fields that don't implement `Copy` as long as they don't have any drop glue.
(removed, untagged_unions, "1.13.0", Some(55149),
Some("unions with `Copy` and `ManuallyDrop` fields are stable; there is no intent to stabilize more")),
/// Allows `#[unwind(..)]`.
///
/// Permits specifying whether a function should permit unwinding or abort on unwind.
(removed, unwind_attributes, "1.56.0", Some(58760), Some("use the C-unwind ABI instead")),
(removed, visible_private_types, "1.0.0", None, None),
// !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!!
// Features are listed in alphabetical order. Tidy will fail if you don't keep it this way.
// !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!!
// -------------------------------------------------------------------------
// feature-group-end: removed features
// -------------------------------------------------------------------------
);
|
