Port #[pointee] to the new attribute parsing infrastructure

Signed-off-by: Jonathan Brouwer <jonathantbrouwer@gmail.com>

Author: JonathanBrouwer

compiler/rustc_attr_data_structures/src/attributes.rs

@@ -340,6 +340,9 @@ pub enum AttributeKind {
     /// Represents `#[path]`
     Path(Symbol, Span),
 
+    /// Represents `#[pointee]`
+    Pointee(Span),
+
     /// Represents `#[rustc_pub_transparent]` (used by the `repr_transparent_external_private_fields` lint).
     PubTransparent(Span),
 

compiler/rustc_attr_data_structures/src/encode_cross_crate.rs

@@ -54,6 +54,7 @@ impl AttributeKind {
             ParenSugar(..) => No,
             PassByValue(..) => Yes,
             Path(..) => No,
+            Pointee(..) => No,
             PubTransparent(..) => Yes,
             Repr { .. } => No,
             RustcLayoutScalarValidRangeEnd(..) => Yes,

compiler/rustc_attr_parsing/src/attributes/traits.rs

@@ -145,3 +145,10 @@ impl<S: Stage> NoArgsAttributeParser<S> for FundamentalParser {
     const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
     const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::Fundamental;
 }
+
+pub(crate) struct PointeeParser;
+impl<S: Stage> NoArgsAttributeParser<S> for PointeeParser {
+    const PATH: &[Symbol] = &[sym::pointee];
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+    const CREATE: fn(Span) -> AttributeKind = AttributeKind::Pointee;
+}

compiler/rustc_attr_parsing/src/context.rs

@@ -46,8 +46,8 @@ use crate::attributes::test_attrs::IgnoreParser;
 use crate::attributes::traits::{
     AllowIncoherentImplParser, CoherenceIsCoreParser, CoinductiveParser, ConstTraitParser,
     DenyExplicitImplParser, DoNotImplementViaObjectParser, FundamentalParser, MarkerParser,
-    ParenSugarParser, SkipDuringMethodDispatchParser, SpecializationTraitParser, TypeConstParser,
-    UnsafeSpecializationMarkerParser,
+    ParenSugarParser, PointeeParser, SkipDuringMethodDispatchParser, SpecializationTraitParser,
+    TypeConstParser, UnsafeSpecializationMarkerParser,
 };
 use crate::attributes::transparency::TransparencyParser;
 use crate::attributes::{AttributeParser as _, Combine, Single, WithoutArgs};
@@ -173,6 +173,7 @@ attribute_parsers!(
         Single<WithoutArgs<NonExhaustiveParser>>,
         Single<WithoutArgs<ParenSugarParser>>,
         Single<WithoutArgs<PassByValueParser>>,
+        Single<WithoutArgs<PointeeParser>>,
         Single<WithoutArgs<PubTransparentParser>>,
         Single<WithoutArgs<SpecializationTraitParser>>,
         Single<WithoutArgs<StdInternalSymbolParser>>,

compiler/rustc_parse/src/validate_attr.rs

@@ -299,6 +299,7 @@ pub fn check_builtin_meta_item(
                 | sym::align
                 | sym::deprecated
                 | sym::optimize
+                | sym::pointee
                 | sym::cold
                 | sym::target_feature
                 | sym::rustc_allow_const_fn_unstable

compiler/rustc_passes/src/check_attr.rs

@@ -240,6 +240,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     AttributeKind::BodyStability { .. }
                     | AttributeKind::ConstStabilityIndirect
                     | AttributeKind::MacroTransparency(_)
+                    | AttributeKind::Pointee(..)
                     | AttributeKind::Dummy,
                 ) => { /* do nothing  */ }
                 Attribute::Parsed(AttributeKind::AsPtr(attr_span)) => {
@@ -368,7 +369,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                             | sym::cfg_attr_trace
                             // need to be fixed
                             | sym::cfi_encoding // FIXME(cfi_encoding)
-                            | sym::pointee // FIXME(derive_coerce_pointee)
                             | sym::omit_gdb_pretty_printer_section // FIXME(omit_gdb_pretty_printer_section)
                             | sym::instruction_set // broken on stable!!!
                             | sym::windows_subsystem // broken on stable!!!