Rollup merge of #111686 - cjgillot:no-foreign-item, r=compiler-errors

Retire is_foreign_item query.

This can be written in terms of `DefKind`. This does not deserve the cost of a query.

compiler/rustc_middle/src/hir/mod.rs

@@ -10,6 +10,7 @@ use crate::query::Providers;
 use crate::ty::{EarlyBinder, ImplSubject, TyCtxt};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::{par_for_each_in, DynSend, DynSync};
+use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::*;
 use rustc_query_system::ich::StableHashingContext;
@@ -110,6 +111,12 @@ impl<'tcx> TyCtxt<'tcx> {
             None => self.type_of(def_id).map_bound(ImplSubject::Inherent),
         }
     }
+
+    /// Returns `true` if this is a foreign item (i.e., linked via `extern { ... }`).
+    pub fn is_foreign_item(self, def_id: impl Into<DefId>) -> bool {
+        self.opt_parent(def_id.into())
+            .map_or(false, |parent| matches!(self.def_kind(parent), DefKind::ForeignMod))
+    }
 }
 
 pub fn provide(providers: &mut Providers) {

compiler/rustc_middle/src/query/mod.rs

@@ -726,12 +726,6 @@ rustc_queries! {
         desc { |tcx| "checking if item is promotable: `{}`", tcx.def_path_str(key) }
     }
 
-    /// Returns `true` if this is a foreign item (i.e., linked via `extern { ... }`).
-    query is_foreign_item(key: DefId) -> bool {
-        desc { |tcx| "checking if `{}` is a foreign item", tcx.def_path_str(key) }
-        separate_provide_extern
-    }
-
     /// Returns `Some(generator_kind)` if the node pointed to by `def_id` is a generator.
     query generator_kind(def_id: DefId) -> Option<hir::GeneratorKind> {
         desc { |tcx| "looking up generator kind of `{}`", tcx.def_path_str(def_id) }