Make OsStr usable with queries

Author: madsmtm

compiler/rustc_data_structures/src/stable_hasher.rs

@@ -565,6 +565,8 @@ where
     }
 }
 
+impl_stable_traits_for_trivial_type!(::std::ffi::OsStr);
+
 impl_stable_traits_for_trivial_type!(::std::path::Path);
 impl_stable_traits_for_trivial_type!(::std::path::PathBuf);
 

compiler/rustc_middle/src/query/erase.rs

@@ -1,3 +1,4 @@
+use std::ffi::OsStr;
 use std::intrinsics::transmute_unchecked;
 use std::mem::MaybeUninit;
 
@@ -65,6 +66,10 @@ impl<T> EraseType for &'_ [T] {
     type Result = [u8; size_of::<&'static [()]>()];
 }
 
+impl EraseType for &'_ OsStr {
+    type Result = [u8; size_of::<&'static OsStr>()];
+}
+
 impl<T> EraseType for &'_ ty::List<T> {
     type Result = [u8; size_of::<&'static ty::List<()>>()];
 }
@@ -180,6 +185,10 @@ impl<T> EraseType for Option<&'_ [T]> {
     type Result = [u8; size_of::<Option<&'static [()]>>()];
 }
 
+impl EraseType for Option<&'_ OsStr> {
+    type Result = [u8; size_of::<Option<&'static OsStr>>()];
+}
+
 impl EraseType for Option<mir::DestructuredConstant<'_>> {
     type Result = [u8; size_of::<Option<mir::DestructuredConstant<'static>>>()];
 }

compiler/rustc_middle/src/query/keys.rs

@@ -1,5 +1,7 @@
 //! Defines the set of legal keys that can be used in queries.
 
+use std::ffi::OsStr;
+
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE, LocalDefId, LocalModDefId, ModDefId};
 use rustc_hir::hir_id::{HirId, OwnerId};
 use rustc_query_system::dep_graph::DepNodeIndex;
@@ -492,6 +494,22 @@ impl Key for Option<Symbol> {
     }
 }
 
+impl<'tcx> Key for &'tcx OsStr {
+    type Cache<V> = DefaultCache<Self, V>;
+
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for Option<&'tcx OsStr> {
+    type Cache<V> = DefaultCache<Self, V>;
+
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
 /// Canonical query goals correspond to abstract trait operations that
 /// are not tied to any crate in particular.
 impl<'tcx, T: Clone> Key for CanonicalQueryInput<'tcx, T> {