1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
//! List of the removed feature gates.
use super::{to_nonzero, Feature, State};
use rustc_span::symbol::sym;
macro_rules! declare_features {
($(
$(#[doc = $doc:tt])* (removed, $feature:ident, $ver:expr, $issue:expr, None, $reason:expr),
)+) => {
/// Represents unstable features which have since been removed (it was once Active)
pub const REMOVED_FEATURES: &[Feature] = &[
$(
Feature {
state: State::Removed { reason: $reason },
name: sym::$feature,
since: $ver,
issue: to_nonzero($issue),
edition: None,
}
),+
];
};
($(
$(#[doc = $doc:tt])* (stable_removed, $feature:ident, $ver:expr, $issue:expr, None),
)+) => {
/// Represents stable features which have since been removed (it was once Accepted)
pub const STABLE_REMOVED_FEATURES: &[Feature] = &[
$(
Feature {
state: State::Stabilized { reason: None },
name: sym::$feature,
since: $ver,
issue: to_nonzero($issue),
edition: None,
}
),+
];
};
}
#[rustfmt::skip]
declare_features! (
// -------------------------------------------------------------------------
// feature-group-start: removed features
// -------------------------------------------------------------------------
(removed, advanced_slice_patterns, "1.0.0", Some(62254), None,
Some("merged into `#![feature(slice_patterns)]`")),
(removed, allocator, "1.0.0", None, None, None),
/// Allows a test to fail without failing the whole suite.
(removed, allow_fail, "1.19.0", Some(46488), None, Some("removed due to no clear use cases")),
(removed, await_macro, "1.38.0", Some(50547), None,
Some("subsumed by `.await` syntax")),
/// Allows comparing raw pointers during const eval.
(removed, const_compare_raw_pointers, "1.46.0", Some(53020), None,
Some("cannot be allowed in const eval in any meaningful way")),
/// Allows non-trivial generic constants which have to be manually propagated upwards.
(removed, const_evaluatable_checked, "1.48.0", Some(76560), None, Some("renamed to `generic_const_exprs`")),
/// Allows the definition of `const` functions with some advanced features.
(removed, const_fn, "1.54.0", Some(57563), None,
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), None,
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), None,
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), None,
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), None,
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), None, Some("removed in favor of `pub(crate)`")),
/// Allows using custom attributes (RFC 572).
(removed, custom_attribute, "1.0.0", Some(29642), None,
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), None,
Some("subsumed by `#[proc_macro_derive]`")),
/// Allows using `#[doc(keyword = "...")]`.
(removed, doc_keyword, "1.28.0", Some(51315), None,
Some("merged into `#![feature(rustdoc_internals)]`")),
/// Allows using `doc(primitive)` without a future-incompat warning.
(removed, doc_primitive, "1.56.0", Some(88070), None,
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), None,
Some("renamed to `doc_notable_trait`")),
/// Allows using `#[unsafe_destructor_blind_to_params]` (RFC 1238).
(removed, dropck_parametricity, "1.38.0", Some(28498), None, None),
/// Allows defining `existential type`s.
(removed, existential_type, "1.38.0", Some(63063), None,
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), None,
Some("subsumed by `::foo::bar` paths")),
/// Allows `#[doc(include = "some-file")]`.
(removed, external_doc, "1.54.0", Some(44732), None,
Some("use #[doc = include_str!(\"filename\")] instead, which handles macro invocations")),
/// Allows `impl Trait` in bindings (`let`, `const`, `static`).
(removed, impl_trait_in_bindings, "1.55.0", Some(63065), None,
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, 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), None,
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), None,
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), None, Some("superseded by `generic_const_exprs`")),
/// Allows using the `#[link_args]` attribute.
(removed, link_args, "1.53.0", Some(29596), None,
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), None,
Some("subsumed by `pub use`")),
/// Allows using `#[main]` to replace the entrypoint `#[lang = "start"]` calls.
(removed, main, "1.53.0", Some(29634), None, None),
(removed, managed_boxes, "1.0.0", None, 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), None,
Some("removed in favor of full type_alias_impl_trait")),
(removed, needs_allocator, "1.4.0", Some(27389), None,
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, None),
/// Allows `#[no_debug]`.
(removed, no_debug, "1.43.0", Some(29721), None, Some("removed due to lack of demand")),
/// Allows using `#[on_unimplemented(..)]` on traits.
/// (Moved to `rustc_attrs`.)
(removed, on_unimplemented, "1.40.0", None, 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, None),
/// Allows features specific to OIBIT (now called auto traits).
/// Renamed to `auto_traits`.
(removed, optin_builtin_traits, "1.0.0", Some(13231), None,
Some("renamed to `auto_traits`")),
/// Allows overlapping impls of marker traits.
(removed, overlapping_marker_traits, "1.42.0", Some(29864), None,
Some("removed in favor of `#![feature(marker_trait_attr)]`")),
(removed, panic_implementation, "1.28.0", Some(44489), None,
Some("subsumed by `#[panic_handler]`")),
/// Allows using `#[plugin_registrar]` on functions.
(removed, plugin_registrar, "1.54.0", Some(29597), None,
Some("a __rustc_plugin_registrar symbol must now be defined instead")),
(removed, proc_macro_expr, "1.27.0", Some(54727), None,
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, proc_macro_gen, "1.27.0", Some(54727), None,
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, proc_macro_mod, "1.27.0", Some(54727), None,
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, proc_macro_non_items, "1.27.0", Some(54727), None,
Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
(removed, pub_macro_rules, "1.53.0", Some(78855), None,
Some("removed due to being incomplete, in particular it does not work across crates")),
(removed, pushpop_unsafe, "1.2.0", None, None, None),
(removed, quad_precision_float, "1.0.0", None, None, None),
(removed, quote, "1.33.0", Some(29601), None, None),
(removed, reflect, "1.0.0", Some(27749), None, None),
/// Allows using the `#[register_attr]` attribute.
(removed, register_attr, "1.65.0", Some(66080), None,
Some("removed in favor of `#![register_tool]`")),
/// Allows using the macros:
/// + `__diagnostic_used`
/// + `__register_diagnostic`
/// +`__build_diagnostic_array`
(removed, rustc_diagnostic_macros, "1.38.0", None, None, None),
/// Allows identifying crates that contain sanitizer runtimes.
(removed, sanitizer_runtime, "1.17.0", None, None, None),
(removed, simd, "1.0.0", Some(27731), None,
Some("removed in favor of `#[repr(simd)]`")),
/// Allows `#[link(kind = "static-nobundle", ...)]`.
(removed, static_nobundle, "1.16.0", Some(37403), None,
Some(r#"subsumed by `#[link(kind = "static", modifiers = "-bundle", ...)]`"#)),
(removed, struct_inherit, "1.0.0", None, None, None),
(removed, test_removed_feature, "1.0.0", None, None, None),
/// Allows using items which are missing stability attributes
(removed, unmarked_api, "1.0.0", None, None, None),
(removed, unsafe_no_drop_flag, "1.0.0", None, 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), None,
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), None, Some("use the C-unwind ABI instead")),
(removed, visible_private_types, "1.0.0", None, None, None),
// !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!!
// Features are listed in alphabetical order. Tidy will fail if you don't keep it this way.
// !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!! !!!!
// -------------------------------------------------------------------------
// feature-group-end: removed features
// -------------------------------------------------------------------------
);
#[rustfmt::skip]
declare_features! (
(stable_removed, no_stack_check, "1.0.0", None, None),
);
|
