1use std::num::{NonZero, NonZeroU32};
4
5use rustc_span::sym;
6
7use super::{Feature, to_nonzero};
8
9pub struct RemovedFeature {
10 pub feature: Feature,
11 pub reason: Option<&'static str>,
12 pub pull: Option<NonZero<u32>>,
13}
14
15macro_rules! opt_nonzero_u32 {
16 () => {
17 None
18 };
19 ($val:expr) => {
20 Some(NonZeroU32::new($val).unwrap())
21 };
22}
23
24macro_rules! declare_features {
25 ($(
26 $(#[doc = $doc:tt])* (removed, $feature:ident, $ver:expr, $issue:expr, $reason:expr $(, $pull:expr)?),
27 )+) => {
28 pub static REMOVED_LANG_FEATURES: &[RemovedFeature] = &[
30 $(RemovedFeature {
31 feature: Feature {
32 name: sym::$feature,
33 since: $ver,
34 issue: to_nonzero($issue),
35 },
36 reason: $reason,
37 pull: opt_nonzero_u32!($($pull)?),
38 }),+
39 ];
40 };
41}
42
43#[rustfmt::skip]
44declare_features! (
45 (removed, abi_amdgpu_kernel, "1.77.0", Some(51575), None, 120495),
57 (removed, abi_c_cmse_nonsecure_call, "1.90.0", Some(81391), Some("renamed to abi_cmse_nonsecure_call"), 142146),
58 (removed, advanced_slice_patterns, "1.42.0", Some(62254),
59 Some("merged into `#![feature(slice_patterns)]`"), 67712),
60 (removed, allocator, "1.0.0", None, None),
61 (removed, allow_fail, "1.60.0", Some(46488), Some("removed due to no clear use cases"), 93416),
63 (removed, await_macro, "1.38.0", Some(50547),
64 Some("subsumed by `.await` syntax"), 62293),
65 (removed, box_syntax, "1.70.0", Some(49733), Some("replaced with `#[rustc_box]`"), 108471),
67 (removed, capture_disjoint_fields, "1.69.0", Some(53488), Some("stabilized in Rust 2021"), 108550),
69 (removed, const_compare_raw_pointers, "1.46.0", Some(53020),
71 Some("cannot be allowed in const eval in any meaningful way"), 73398),
72 (removed, const_eval_limit, "1.72.0", Some(67217), Some("removed the limit entirely"), 103877),
74 (removed, const_evaluatable_checked, "1.56.0", Some(76560), Some("renamed to `generic_const_exprs`"), 88369),
76 (removed, const_fn, "1.54.0", Some(57563),
78 Some("split into finer-grained feature gates"), 85109),
79 (removed, const_generics, "1.56.0", Some(44580),
81 Some("removed in favor of `#![feature(adt_const_params)]` and `#![feature(generic_const_exprs)]`"), 88369),
82 (removed, const_in_array_repeat_expressions, "1.51.0", Some(49147),
84 Some("removed due to causing promotable bugs"), 80404),
85 (removed, const_raw_ptr_to_usize_cast, "1.55.0", Some(51910),
87 Some("at compile-time, pointers do not have an integer value, so these casts cannot be properly supported"), 87020),
88 (removed, const_trait_bound_opt_out, "1.56.0", Some(67794),
90 Some("Removed in favor of `[const]` bound in #![feature(const_trait_impl)]"), 88328),
91 (removed, crate_visibility_modifier, "1.63.0", Some(53120), Some("removed in favor of `pub(crate)`"), 97254),
93 (removed, custom_attribute, "1.0.0", Some(29642),
95 Some("removed in favor of `#![register_tool]` and `#![register_attr]`"), 66070),
96 (removed, custom_derive, "1.32.0", Some(29644),
98 Some("subsumed by `#[proc_macro_derive]`")),
99 (removed, default_type_parameter_fallback, "1.82.0", Some(27336),
101 Some("never properly implemented; requires significant design work"), 127655),
102 (removed, derive_smart_pointer, "1.84.0", Some(123430), Some("replaced by `CoercePointee`"), 131284),
104 (removed, doc_auto_cfg, "CURRENT_RUSTC_VERSION", Some(43781), Some("merged into `doc_cfg`"), 138907),
106 (removed, doc_cfg_hide, "CURRENT_RUSTC_VERSION", Some(43781), Some("merged into `doc_cfg`"), 138907),
108 (removed, doc_keyword, "1.58.0", Some(51315),
110 Some("merged into `#![feature(rustdoc_internals)]`"), 90420),
111 (removed, doc_primitive, "1.58.0", Some(88070),
113 Some("merged into `#![feature(rustdoc_internals)]`"), 90420),
114 (removed, doc_spotlight, "1.53.0", Some(45040),
118 Some("renamed to `doc_notable_trait`"), 80965),
119 (removed, dropck_parametricity, "1.38.0", Some(28498), None),
121 (removed, dyn_compatible_for_dispatch, "1.87.0", Some(43561),
129 Some("removed, not used heavily and represented additional complexity in dyn compatibility"), 136522),
130 (removed, dyn_star, "1.65.0", Some(102425),
132 Some("removed as it was no longer necessary for AFIDT (async fn in dyn trait) support")),
133 (removed, effects, "1.84.0", Some(102090),
135 Some("removed, redundant with `#![feature(const_trait_impl)]`"), 132479),
136 (removed, existential_type, "1.38.0", Some(63063),
138 Some("removed in favor of `#![feature(type_alias_impl_trait)]`")),
139 (removed, extern_in_paths, "1.33.0", Some(55600),
141 Some("subsumed by `::foo::bar` paths"), 57572),
142 (removed, external_doc, "1.54.0", Some(44732),
144 Some("use #[doc = include_str!(\"filename\")] instead, which handles macro invocations"), 85457),
145 (removed, ffi_returns_twice, "1.78.0", Some(58314),
147 Some("being investigated by the ffi-unwind project group"), 120502),
148 (removed, generator_clone, "1.75.0", Some(95360), Some("renamed to `coroutine_clone`"), 116958),
150 (removed, generators, "1.75.0", Some(43122), Some("renamed to `coroutines`"), 116958),
152 (removed, generic_associated_types_extended, "1.85.0", Some(95451),
154 Some(
155 "feature needs overhaul and reimplementation pending \
156 better implied higher-ranked implied bounds support"
157 ),
158 133768
159 ),
160 (removed, import_shadowing, "1.0.0", None, None),
161 (removed, in_band_lifetimes, "1.61.0", Some(44524),
163 Some("removed due to unsolved ergonomic questions and added lifetime resolution complexity"), 93845),
164 (removed, infer_static_outlives_requirements, "1.63.0", Some(54185),
166 Some("removed as it caused some confusion and discussion was inactive for years"), 97875),
167 (removed, inline_const_pat, "1.88.0", Some(76001),
169 Some("removed due to implementation concerns as it requires significant refactorings"), 138492),
170 (removed, lazy_normalization_consts, "1.56.0", Some(72219), Some("superseded by `generic_const_exprs`"), 88369),
172 (removed, lifetime_capture_rules_2024, "1.87.0", None, Some("unnecessary -- use edition 2024 instead"), 136787),
174 (removed, link_args, "1.53.0", Some(29596),
176 Some("removed in favor of using `-C link-arg=ARG` on command line, \
177 which is available from cargo build scripts with `cargo:rustc-link-arg` now"), 83820),
178 (removed, macro_reexport, "1.0.0", Some(29638),
179 Some("subsumed by `pub use`"), 49982),
180 (removed, main, "1.53.0", Some(29634), None, 84217),
182 (removed, managed_boxes, "1.0.0", None, None),
183 (removed, min_type_alias_impl_trait, "1.56.0", Some(63063),
185 Some("removed in favor of full type_alias_impl_trait"), 87564),
186 (removed, mut_preserve_binding_mode_2024, "1.80.0", Some(123076), Some("superseded by `ref_pat_eat_one_layer_2024`"), 125168),
188 (removed, needs_allocator, "1.4.0", Some(27389),
189 Some("subsumed by `#![feature(allocator_internals)]`")),
190 (removed, negate_unsigned, "1.0.0", Some(29645), None),
192 (removed, no_coverage, "1.74.0", Some(84605), Some("renamed to `coverage_attribute`"), 114656),
195 (removed, no_debug, "1.43.0", Some(29721), Some("removed due to lack of demand"), 69667),
197 (removed, no_sanitize, "1.91.0", Some(39699), Some(r#"renamed to sanitize(xyz = "on|off")"#), 142681),
200 (removed, no_stack_check, "1.0.0", None, None, 40110),
205 (removed, object_safe_for_dispatch, "1.83.0", Some(43561),
208 Some("renamed to `dyn_compatible_for_dispatch`"), 131511),
209 (removed, omit_gdb_pretty_printer_section, "1.91.0", None, None, 144738),
211 (removed, on_unimplemented, "1.40.0", None, None, 65794),
214 (removed, opt_out_copy, "1.0.0", None, None, 20740),
216 (removed, optin_builtin_traits, "1.50.0", Some(13231),
219 Some("renamed to `auto_traits`"), 79336),
220 (removed, overlapping_marker_traits, "1.42.0", Some(29864),
222 Some("removed in favor of `#![feature(marker_trait_attr)]`"), 68544),
223 (removed, panic_implementation, "1.28.0", Some(44489),
224 Some("subsumed by `#[panic_handler]`"), 53619),
225 (removed, platform_intrinsics, "1.78.0", Some(27731),
227 Some("SIMD intrinsics use the regular intrinsics ABI now"), 121516),
228 (removed, plugin, "1.75.0", Some(29597),
230 Some("plugins are no longer supported"), 116412),
231 (removed, plugin_registrar, "1.75.0", Some(29597),
233 Some("plugins are no longer supported"), 116412),
234 (removed, precise_pointer_size_matching, "1.76.0", Some(56354),
236 Some("removed in favor of half-open ranges"), 118598),
237 (removed, pref_align_of, "1.89.0", Some(91971),
238 Some("removed due to marginal use and inducing compiler complications")),
239 (removed, proc_macro_expr, "1.27.0", Some(54727),
240 Some("subsumed by `#![feature(proc_macro_hygiene)]`"), 52121),
241 (removed, proc_macro_gen, "1.27.0", Some(54727),
242 Some("subsumed by `#![feature(proc_macro_hygiene)]`"), 52121),
243 (removed, proc_macro_mod, "1.27.0", Some(54727),
244 Some("subsumed by `#![feature(proc_macro_hygiene)]`"), 52121),
245 (removed, proc_macro_non_items, "1.27.0", Some(54727),
246 Some("subsumed by `#![feature(proc_macro_hygiene)]`"), 52121),
247 (removed, pub_macro_rules, "1.53.0", Some(78855),
248 Some("removed due to being incomplete, in particular it does not work across crates")),
249 (removed, pushpop_unsafe, "1.2.0", None, None),
250 (removed, quad_precision_float, "1.0.0", None, None),
251 (removed, quote, "1.33.0", Some(29601), None),
252 (removed, ref_pat_everywhere, "1.80.0", Some(123076), Some("superseded by `ref_pat_eat_one_layer_2024"), 125168),
253 (removed, reflect, "1.0.0", Some(27749), None),
254 (removed, register_attr, "1.65.0", Some(66080),
256 Some("removed in favor of `#![register_tool]`"), 66070),
257 (removed, rust_2018_preview, "1.76.0", None,
258 Some("2018 Edition preview is no longer relevant")),
259 (removed, rustc_diagnostic_macros, "1.38.0", None, None, 64139),
264 (removed, sanitizer_runtime, "1.17.0", None, None, 65241),
266 (removed, simd, "1.0.0", Some(27731), Some("removed in favor of `#[repr(simd)]`")),
267 (removed, start, "1.86.0", Some(29633), Some("not portable enough and never RFC'd"), 134299),
269 (removed, static_nobundle, "1.63.0", Some(37403),
271 Some(r#"subsumed by `#[link(kind = "static", modifiers = "-bundle", ...)]`"#), 95818),
272 (removed, struct_inherit, "1.0.0", None, None),
273 (removed, test_removed_feature, "1.0.0", None, None),
274 (removed, unmarked_api, "1.0.0", None, None),
276 (removed, unnamed_fields, "1.83.0", Some(49804), Some("feature needs redesign"), 131045),
278 (removed, unsafe_no_drop_flag, "1.0.0", None, None),
279 (removed, unsized_locals, "1.89.0", Some(48055), Some("removed due to implementation concerns; see https://github.com/rust-lang/rust/issues/111942")),
281 (removed, unsized_tuple_coercion, "1.87.0", Some(42877),
282 Some("The feature restricts possible layouts for tuples, and this restriction is not worth it."), 137728),
283 (removed, untagged_unions, "1.64.0", Some(55149),
285 Some("unions with `Copy` and `ManuallyDrop` fields are stable; there is no intent to stabilize more"), 97995),
286 (removed, unwind_attributes, "1.56.0", Some(58760), Some("use the C-unwind ABI instead"), 86155),
290 (removed, visible_private_types, "1.0.0", None, None),
291 (removed, wasm_abi, "1.81.0", Some(83788),
293 Some("non-standard wasm ABI is no longer supported"), 127605),
294 (removed, concat_idents, "1.90.0", Some(29599),
311 Some("use the `${concat(..)}` metavariable expression instead"), 142704),
312 );