Remove the type_const attribute

Author: Keith-Cancel

compiler/rustc_attr_parsing/src/attributes/traits.rs

@@ -66,15 +66,6 @@ impl<S: Stage> NoArgsAttributeParser<S> for ParenSugarParser {
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::RustcParenSugar;
 }
 
-pub(crate) struct TypeConstParser;
-impl<S: Stage> NoArgsAttributeParser<S> for TypeConstParser {
-    const PATH: &[Symbol] = &[sym::type_const];
-    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
-    const ALLOWED_TARGETS: AllowedTargets =
-        AllowedTargets::AllowList(&[Allow(Target::Const), Allow(Target::AssocConst)]);
-    const CREATE: fn(Span) -> AttributeKind = AttributeKind::TypeConst;
-}
-
 // Markers
 
 pub(crate) struct MarkerParser;

compiler/rustc_attr_parsing/src/context.rs

@@ -295,7 +295,6 @@ attribute_parsers!(
         Single<WithoutArgs<StdInternalSymbolParser>>,
         Single<WithoutArgs<ThreadLocalParser>>,
         Single<WithoutArgs<TrackCallerParser>>,
-        Single<WithoutArgs<TypeConstParser>>,
         Single<WithoutArgs<UnsafeSpecializationMarkerParser>>,
         // tidy-alphabetical-end
     ];

compiler/rustc_feature/src/builtin_attrs.rs

@@ -888,13 +888,6 @@ pub static BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         EncodeCrossCrate::Yes, experimental!(patchable_function_entry)
     ),
 
-    // Probably temporary component of min_generic_const_args.
-    // `#[type_const] const ASSOC: usize;`
-    gated!(
-        type_const, Normal, template!(Word), ErrorFollowing,
-        EncodeCrossCrate::Yes, min_generic_const_args, experimental!(type_const),
-    ),
-
     // The `#[loop_match]` and `#[const_continue]` attributes are part of the
     // lang experiment for RFC 3720 tracked in:
     //

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -1285,9 +1285,6 @@ pub enum AttributeKind {
     /// Represents `#[track_caller]`
     TrackCaller(Span),
 
-    /// Represents `#[type_const]`.
-    TypeConst(Span),
-
     /// Represents `#[type_length_limit]`
     TypeLengthLimit { attr_span: Span, limit_span: Span, limit: Limit },
 

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -167,7 +167,6 @@ impl AttributeKind {
             TargetFeature { .. } => No,
             ThreadLocal => No,
             TrackCaller(..) => Yes,
-            TypeConst(..) => Yes,
             TypeLengthLimit { .. } => No,
             UnstableFeatureBound(..) => No,
             Used { .. } => No,

compiler/rustc_passes/src/check_attr.rs

@@ -354,7 +354,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     | AttributeKind::RustcVarianceOfOpaques
                     | AttributeKind::ShouldPanic { .. }
                     | AttributeKind::ThreadLocal
-                    | AttributeKind::TypeConst{..}
                     | AttributeKind::TypeLengthLimit { .. }
                     | AttributeKind::UnstableFeatureBound(..)
                     | AttributeKind::Used { .. }

compiler/rustc_span/src/symbol.rs

@@ -2339,7 +2339,6 @@ symbols! {
         type_ascribe,
         type_ascription,
         type_changing_struct_update,
-        type_const,
         type_id,
         type_id_eq,
         type_info,