Factor out conservative_is_privately_uninhabited

compiler/rustc_middle/src/query/mod.rs

@@ -2078,17 +2078,6 @@ rustc_queries! {
         desc { "normalizing opaque types in `{:?}`", key }
     }
 
-    /// Checks whether a type is definitely uninhabited. This is
-    /// conservative: for some types that are uninhabited we return `false`,
-    /// but we only return `true` for types that are definitely uninhabited.
-    /// `ty.conservative_is_privately_uninhabited` implies that any value of type `ty`
-    /// will be `Abi::Uninhabited`. (Note that uninhabited types may have nonzero
-    /// size, to account for partial initialisation. See #49298 for details.)
-    query conservative_is_privately_uninhabited(key: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
-        desc { "conservatively checking if `{}` is privately uninhabited", key.value }
-        remap_env_constness
-    }
-
     query limits(key: ()) -> Limits {
         desc { "looking up limits" }
     }

compiler/rustc_middle/src/ty/inhabitedness/inhabited_predicate.rs

@@ -41,6 +41,13 @@ impl<'tcx> InhabitedPredicate<'tcx> {
         self.apply_inner(tcx, param_env, &|_| Err(())).ok()
     }
 
+    /// Same as `apply`, but `NotInModule(_)` predicates yield `false`. That is,
+    /// privately uninhabited types are considered always uninhabited.
+    pub fn apply_ignore_module(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> bool {
+        let Ok(result) = self.apply_inner::<!>(tcx, param_env, &|_| Ok(true));
+        result
+    }
+
     fn apply_inner<E>(
         self,
         tcx: TyCtxt<'tcx>,

compiler/rustc_middle/src/ty/inhabitedness/mod.rs

@@ -169,6 +169,15 @@ impl<'tcx> Ty<'tcx> {
     ) -> bool {
         self.inhabited_predicate(tcx).apply(tcx, param_env, module)
     }
+
+    /// Returns true if the type is uninhabited without regard to visibility
+    pub fn is_privately_uninhabited(
+        self,
+        tcx: TyCtxt<'tcx>,
+        param_env: ty::ParamEnv<'tcx>,
+    ) -> bool {
+        !self.inhabited_predicate(tcx).apply_ignore_module(tcx, param_env)
+    }
 }
 
 /// N.B. this query should only be called through `Ty::inhabited_predicate`