diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs
index e86421f2150db..3b7e0d82d0f62 100644
--- a/compiler/rustc_feature/src/builtin_attrs.rs
+++ b/compiler/rustc_feature/src/builtin_attrs.rs
@@ -1186,3 +1186,11 @@ pub static BUILTIN_ATTRIBUTE_MAP: LazyLock<FxHashMap<Symbol, &BuiltinAttribute>>
}
map
});
+
+pub fn is_stable_diagnostic_attribute(sym: Symbol, features: &Features) -> bool {
+ match sym {
+ sym::on_unimplemented => true,
+ sym::do_not_recommend => features.do_not_recommend,
+ _ => false,
+ }
+}
diff --git a/compiler/rustc_feature/src/lib.rs b/compiler/rustc_feature/src/lib.rs
index adaaba3cd235e..fe12930e6b9d6 100644
--- a/compiler/rustc_feature/src/lib.rs
+++ b/compiler/rustc_feature/src/lib.rs
@@ -130,8 +130,9 @@ pub fn find_feature_issue(feature: Symbol, issue: GateIssue) -> Option<NonZero<u
pub use accepted::ACCEPTED_FEATURES;
pub use builtin_attrs::{
deprecated_attributes, encode_cross_crate, find_gated_cfg, is_builtin_attr_name,
- is_valid_for_get_attr, AttributeDuplicates, AttributeGate, AttributeSafety, AttributeTemplate,
- AttributeType, BuiltinAttribute, GatedCfg, BUILTIN_ATTRIBUTES, BUILTIN_ATTRIBUTE_MAP,
+ is_stable_diagnostic_attribute, is_valid_for_get_attr, AttributeDuplicates, AttributeGate,
+ AttributeSafety, AttributeTemplate, AttributeType, BuiltinAttribute, GatedCfg,
+ BUILTIN_ATTRIBUTES, BUILTIN_ATTRIBUTE_MAP,
};
pub use removed::REMOVED_FEATURES;
pub use unstable::{Features, INCOMPATIBLE_FEATURES, UNSTABLE_FEATURES};
diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs
index 92111805ab422..ac9976148e25c 100644
--- a/compiler/rustc_hir_analysis/src/collect.rs
+++ b/compiler/rustc_hir_analysis/src/collect.rs
@@ -1698,8 +1698,6 @@ fn impl_trait_header(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<ty::ImplTrai
trait_ref: ty::EarlyBinder::bind(trait_ref),
safety: impl_.safety,
polarity: polarity_of_impl(tcx, def_id, impl_, item.span),
- do_not_recommend: tcx.features().do_not_recommend
- && tcx.has_attrs_with_path(def_id, &[sym::diagnostic, sym::do_not_recommend]),
}
})
}
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index c55583b39a6c7..8ccd6db368f7c 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -9,6 +9,7 @@ use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
use rustc_data_structures::memmap::{Mmap, MmapMut};
use rustc_data_structures::sync::{join, par_for_each_in, Lrc};
use rustc_data_structures::temp_dir::MaybeTempDir;
+use rustc_feature::Features;
use rustc_hir as hir;
use rustc_hir::def_id::{LocalDefId, LocalDefIdSet, CRATE_DEF_ID, CRATE_DEF_INDEX, LOCAL_CRATE};
use rustc_hir::definitions::DefPathData;
@@ -797,9 +798,10 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
}
}
-struct AnalyzeAttrState {
+struct AnalyzeAttrState<'a> {
is_exported: bool,
is_doc_hidden: bool,
+ features: &'a Features,
}
/// Returns whether an attribute needs to be recorded in metadata, that is, if it's usable and
@@ -812,7 +814,7 @@ struct AnalyzeAttrState {
/// visibility: this is a piece of data that can be computed once per defid, and not once per
/// attribute. Some attributes would only be usable downstream if they are public.
#[inline]
-fn analyze_attr(attr: &Attribute, state: &mut AnalyzeAttrState) -> bool {
+fn analyze_attr(attr: &Attribute, state: &mut AnalyzeAttrState<'_>) -> bool {
let mut should_encode = false;
if !rustc_feature::encode_cross_crate(attr.name_or_empty()) {
// Attributes not marked encode-cross-crate don't need to be encoded for downstream crates.
@@ -837,6 +839,9 @@ fn analyze_attr(attr: &Attribute, state: &mut AnalyzeAttrState) -> bool {
}
}
}
+ } else if attr.path().starts_with(&[sym::diagnostic]) && attr.path().len() == 2 {
+ should_encode =
+ rustc_feature::is_stable_diagnostic_attribute(attr.path()[1], state.features);
} else {
should_encode = true;
}
@@ -1343,6 +1348,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
let mut state = AnalyzeAttrState {
is_exported: tcx.effective_visibilities(()).is_exported(def_id),
is_doc_hidden: false,
+ features: &tcx.features(),
};
let attr_iter = tcx
.hir()
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 20828067c469c..ff34555920de5 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -3183,8 +3183,7 @@ impl<'tcx> TyCtxt<'tcx> {
/// Whether this is a trait implementation that has `#[diagnostic::do_not_recommend]`
pub fn do_not_recommend_impl(self, def_id: DefId) -> bool {
- matches!(self.def_kind(def_id), DefKind::Impl { of_trait: true })
- && self.impl_trait_header(def_id).is_some_and(|header| header.do_not_recommend)
+ self.get_diagnostic_attr(def_id, sym::do_not_recommend).is_some()
}
}
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index ee70a6346d920..e637ced7139a6 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -263,7 +263,6 @@ pub struct ImplTraitHeader<'tcx> {
pub trait_ref: ty::EarlyBinder<'tcx, ty::TraitRef<'tcx>>,
pub polarity: ImplPolarity,
pub safety: hir::Safety,
- pub do_not_recommend: bool,
}
#[derive(Copy, Clone, PartialEq, Eq, Debug, TypeFoldable, TypeVisitable)]
@@ -1797,6 +1796,37 @@ impl<'tcx> TyCtxt<'tcx> {
}
}
+ /// Get an attribute from the diagnostic attribute namespace
+ ///
+ /// This function requests an attribute with the following structure:
+ ///
+ /// `#[diagnostic::$attr]`
+ ///
+ /// This function performs feature checking, so if an attribute is returned
+ /// it can be used by the consumer
+ pub fn get_diagnostic_attr(
+ self,
+ did: impl Into<DefId>,
+ attr: Symbol,
+ ) -> Option<&'tcx ast::Attribute> {
+ let did: DefId = did.into();
+ if did.as_local().is_some() {
+ // it's a crate local item, we need to check feature flags
+ if rustc_feature::is_stable_diagnostic_attribute(attr, self.features()) {
+ self.get_attrs_by_path(did, &[sym::diagnostic, sym::do_not_recommend]).next()
+ } else {
+ None
+ }
+ } else {
+ // we filter out unstable diagnostic attributes before
+ // encoding attributes
+ debug_assert!(rustc_feature::encode_cross_crate(attr));
+ self.item_attrs(did)
+ .iter()
+ .find(|a| matches!(a.path().as_ref(), [sym::diagnostic, a] if *a == attr))
+ }
+ }
+
pub fn get_attrs_by_path<'attr>(
self,
did: DefId,