1 files changed, 21 insertions, 5 deletions
diff --git a/compiler/rustc_middle/src/ty/typeck_results.rs b/compiler/rustc_middle/src/ty/typeck_results.rs
index 47943b94c..e04dbbff9 100644
--- a/compiler/rustc_middle/src/ty/typeck_results.rs
+++ b/compiler/rustc_middle/src/ty/typeck_results.rs
@@ -20,7 +20,7 @@ use rustc_hir::{
     hir_id::OwnerId,
     HirId, ItemLocalId, ItemLocalMap, ItemLocalSet,
 };
-use rustc_index::vec::{Idx, IndexVec};
+use rustc_index::{Idx, IndexVec};
 use rustc_macros::HashStable;
 use rustc_middle::mir::FakeReadCause;
 use rustc_session::Session;
@@ -151,10 +151,14 @@ pub struct TypeckResults<'tcx> {
     /// this field will be set to `Some(ErrorGuaranteed)`.
     pub tainted_by_errors: Option<ErrorGuaranteed>,
 
-    /// All the opaque types that have hidden types set
-    /// by this function. We also store the
-    /// type here, so that mir-borrowck can use it as a hint for figuring out hidden types,
-    /// even if they are only set in dead code (which doesn't show up in MIR).
+    /// All the opaque types that have hidden types set by this function.
+    /// We also store the type here, so that the compiler can use it as a hint
+    /// for figuring out hidden types, even if they are only set in dead code
+    /// (which doesn't show up in MIR).
+    ///
+    /// These types are mapped back to the opaque's identity substitutions
+    /// (with erased regions), which is why we don't associated substs with any
+    /// of these usages.
     pub concrete_opaque_types: FxIndexMap<LocalDefId, ty::OpaqueHiddenType<'tcx>>,
 
     /// Tracks the minimum captures required for a closure;
@@ -208,6 +212,9 @@ pub struct TypeckResults<'tcx> {
     /// Contains the data for evaluating the effect of feature `capture_disjoint_fields`
     /// on closure size.
     pub closure_size_eval: FxHashMap<LocalDefId, ClosureSizeProfileData<'tcx>>,
+
+    /// Container types and field indices of `offset_of!` expressions
+    offset_of_data: ItemLocalMap<(Ty<'tcx>, Vec<FieldIdx>)>,
 }
 
 /// Whenever a value may be live across a generator yield, the type of that value winds up in the
@@ -280,6 +287,7 @@ impl<'tcx> TypeckResults<'tcx> {
             generator_interior_predicates: Default::default(),
             treat_byte_string_as_slice: Default::default(),
             closure_size_eval: Default::default(),
+            offset_of_data: Default::default(),
         }
     }
 
@@ -530,6 +538,14 @@ impl<'tcx> TypeckResults<'tcx> {
     pub fn coercion_casts(&self) -> &ItemLocalSet {
         &self.coercion_casts
     }
+
+    pub fn offset_of_data(&self) -> LocalTableInContext<'_, (Ty<'tcx>, Vec<FieldIdx>)> {
+        LocalTableInContext { hir_owner: self.hir_owner, data: &self.offset_of_data }
+    }
+
+    pub fn offset_of_data_mut(&mut self) -> LocalTableInContextMut<'_, (Ty<'tcx>, Vec<FieldIdx>)> {
+        LocalTableInContextMut { hir_owner: self.hir_owner, data: &mut self.offset_of_data }
+    }
 }
 
 /// Validate that the given HirId (respectively its `local_id` part) can be