Auto merge of #134294 - matthiaskrgr:rollup-anh6io8, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #134252 (Fix `Path::is_absolute` on Hermit)
 - #134254 (Fix building `std` for Hermit after `c_char` change)
 - #134255 (Update includes in `/library/core/src/error.rs`.)
 - #134261 (Document the symbol Visibility enum)
 - #134262 (Arbitrary self types v2: adjust diagnostic.)
 - #134265 (Rename `ty_def_id` so people will stop using it by accident)
 - #134271 (Arbitrary self types v2: better feature gate test)
 - #134274 (Add check-pass test for `&raw`)

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_middle/src/mir/mono.rs

@@ -294,10 +294,22 @@ pub enum Linkage {
     Common,
 }
 
+/// Specifies the symbol visibility with regards to dynamic linking.
+///
+/// Visibility doesn't have any effect when linkage is internal.
+///
+/// DSO means dynamic shared object, that is a dynamically linked executable or dylib.
 #[derive(Copy, Clone, PartialEq, Debug, HashStable)]
 pub enum Visibility {
+    /// Export the symbol from the DSO and apply overrides of the symbol by outside DSOs to within
+    /// the DSO if the object file format supports this.
     Default,
+    /// Hide the symbol outside of the defining DSO even when external linkage is used to export it
+    /// from the object file.
     Hidden,
+    /// Export the symbol from the DSO, but don't apply overrides of the symbol by outside DSOs to
+    /// within the DSO. Equivalent to default visibility with object file formats that don't support
+    /// overriding exported symbols by another DSO.
     Protected,
 }
 

compiler/rustc_middle/src/query/keys.rs

@@ -41,7 +41,8 @@ pub trait Key: Sized {
         None
     }
 
-    fn ty_def_id(&self) -> Option<DefId> {
+    /// Used to detect when ADT def ids are used as keys in a cycle for better error reporting.
+    fn def_id_for_ty_in_cycle(&self) -> Option<DefId> {
         None
     }
 }
@@ -423,7 +424,7 @@ impl<'tcx> Key for Ty<'tcx> {
         DUMMY_SP
     }
 
-    fn ty_def_id(&self) -> Option<DefId> {
+    fn def_id_for_ty_in_cycle(&self) -> Option<DefId> {
         match *self.kind() {
             ty::Adt(adt, _) => Some(adt.did()),
             ty::Coroutine(def_id, ..) => Some(def_id),
@@ -471,8 +472,8 @@ impl<'tcx, T: Key> Key for ty::PseudoCanonicalInput<'tcx, T> {
         self.value.default_span(tcx)
     }
 
-    fn ty_def_id(&self) -> Option<DefId> {
-        self.value.ty_def_id()
+    fn def_id_for_ty_in_cycle(&self) -> Option<DefId> {
+        self.value.def_id_for_ty_in_cycle()
     }
 }
 
@@ -593,7 +594,7 @@ impl<'tcx> Key for (ValidityRequirement, ty::PseudoCanonicalInput<'tcx, Ty<'tcx>
         DUMMY_SP
     }
 
-    fn ty_def_id(&self) -> Option<DefId> {
+    fn def_id_for_ty_in_cycle(&self) -> Option<DefId> {
         match self.1.value.kind() {
             ty::Adt(adt, _) => Some(adt.did()),
             _ => None,

compiler/rustc_middle/src/values.rs

@@ -100,7 +100,7 @@ impl<'tcx> Value<TyCtxt<'tcx>> for Representability {
         }
         for info in &cycle_error.cycle {
             if info.query.dep_kind == dep_kinds::representability_adt_ty
-                && let Some(def_id) = info.query.ty_def_id
+                && let Some(def_id) = info.query.def_id_for_ty_in_cycle
                 && let Some(def_id) = def_id.as_local()
                 && !item_and_field_ids.iter().any(|&(id, _)| id == def_id)
             {
@@ -182,7 +182,7 @@ impl<'tcx, T> Value<TyCtxt<'tcx>> for Result<T, &'_ ty::layout::LayoutError<'_>>
             &cycle_error.cycle,
             |cycle| {
                 if cycle[0].query.dep_kind == dep_kinds::layout_of
-                    && let Some(def_id) = cycle[0].query.ty_def_id
+                    && let Some(def_id) = cycle[0].query.def_id_for_ty_in_cycle
                     && let Some(def_id) = def_id.as_local()
                     && let def_kind = tcx.def_kind(def_id)
                     && matches!(def_kind, DefKind::Closure)
@@ -209,7 +209,7 @@ impl<'tcx, T> Value<TyCtxt<'tcx>> for Result<T, &'_ ty::layout::LayoutError<'_>>
                         if frame.query.dep_kind != dep_kinds::layout_of {
                             continue;
                         }
-                        let Some(frame_def_id) = frame.query.ty_def_id else {
+                        let Some(frame_def_id) = frame.query.def_id_for_ty_in_cycle else {
                             continue;
                         };
                         let Some(frame_coroutine_kind) = tcx.coroutine_kind(frame_def_id) else {