Add #[rustc_should_not_be_called_on_const_items] attribute

Author: Urgau

compiler/rustc_attr_parsing/src/attributes/lint_helpers.rs

@@ -38,6 +38,17 @@ impl<S: Stage> NoArgsAttributeParser<S> for PassByValueParser {
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::PassByValue;
 }
 
+pub(crate) struct RustcShouldNotBeCalledOnConstItems;
+impl<S: Stage> NoArgsAttributeParser<S> for RustcShouldNotBeCalledOnConstItems {
+    const PATH: &[Symbol] = &[sym::rustc_should_not_be_called_on_const_items];
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
+        Allow(Target::Method(MethodKind::Inherent)),
+        Allow(Target::Method(MethodKind::TraitImpl)),
+    ]);
+    const CREATE: fn(Span) -> AttributeKind = AttributeKind::RustcShouldNotBeCalledOnConstItems;
+}
+
 pub(crate) struct AutomaticallyDerivedParser;
 impl<S: Stage> NoArgsAttributeParser<S> for AutomaticallyDerivedParser {
     const PATH: &[Symbol] = &[sym::automatically_derived];

compiler/rustc_attr_parsing/src/context.rs

@@ -39,6 +39,7 @@ use crate::attributes::link_attrs::{
 };
 use crate::attributes::lint_helpers::{
     AsPtrParser, AutomaticallyDerivedParser, PassByValueParser, PubTransparentParser,
+    RustcShouldNotBeCalledOnConstItems,
 };
 use crate::attributes::loop_match::{ConstContinueParser, LoopMatchParser};
 use crate::attributes::macro_attrs::{
@@ -244,6 +245,7 @@ attribute_parsers!(
         Single<WithoutArgs<RustcCoherenceIsCoreParser>>,
         Single<WithoutArgs<RustcMainParser>>,
         Single<WithoutArgs<RustcPassIndirectlyInNonRusticAbisParser>>,
+        Single<WithoutArgs<RustcShouldNotBeCalledOnConstItems>>,
         Single<WithoutArgs<SpecializationTraitParser>>,
         Single<WithoutArgs<StdInternalSymbolParser>>,
         Single<WithoutArgs<TrackCallerParser>>,

compiler/rustc_feature/src/builtin_attrs.rs

@@ -1267,6 +1267,11 @@ pub static BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         EncodeCrossCrate::Yes,
         "`#[rustc_as_ptr]` is used to mark functions returning pointers to their inner allocations."
     ),
+    rustc_attr!(
+        rustc_should_not_be_called_on_const_items, Normal, template!(Word), ErrorFollowing,
+        EncodeCrossCrate::Yes,
+        "`#[rustc_should_not_be_called_on_const_items]` is used to mark methods that don't make sense to be called on interior mutable consts."
+    ),
     rustc_attr!(
         rustc_pass_by_value, Normal, template!(Word), ErrorFollowing,
         EncodeCrossCrate::Yes,

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -701,6 +701,9 @@ pub enum AttributeKind {
     /// Represents `#[rustc_pass_indirectly_in_non_rustic_abis]`
     RustcPassIndirectlyInNonRusticAbis(Span),
 
+    /// Represents `#[rustc_should_not_be_called_on_const_items]`
+    RustcShouldNotBeCalledOnConstItems(Span),
+
     /// Represents `#[rustc_simd_monomorphize_lane_limit = "N"]`.
     RustcSimdMonomorphizeLaneLimit(Limit),
 

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -91,6 +91,7 @@ impl AttributeKind {
             RustcMain => No,
             RustcObjectLifetimeDefault => No,
             RustcPassIndirectlyInNonRusticAbis(..) => No,
+            RustcShouldNotBeCalledOnConstItems(..) => Yes,
             RustcSimdMonomorphizeLaneLimit(..) => Yes, // Affects layout computation, which needs to work cross-crate
             Sanitize { .. } => No,
             ShouldPanic { .. } => No,

compiler/rustc_passes/src/check_attr.rs

@@ -254,6 +254,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     | AttributeKind::RustcLayoutScalarValidRangeStart(..)
                     | AttributeKind::RustcLayoutScalarValidRangeEnd(..)
                     | AttributeKind::RustcSimdMonomorphizeLaneLimit(..)
+                    | AttributeKind::RustcShouldNotBeCalledOnConstItems(..)
                     | AttributeKind::ExportStable
                     | AttributeKind::FfiConst(..)
                     | AttributeKind::UnstableFeatureBound(..)

compiler/rustc_span/src/symbol.rs

@@ -1986,6 +1986,7 @@ symbols! {
         rustc_regions,
         rustc_reservation_impl,
         rustc_serialize,
+        rustc_should_not_be_called_on_const_items,
         rustc_simd_monomorphize_lane_limit,
         rustc_skip_during_method_dispatch,
         rustc_specialization_trait,