2 files changed, 4 insertions, 4 deletions
diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
index ef13a277207..f564f5e99e8 100644
--- a/compiler/rustc_middle/src/query/mod.rs
+++ b/compiler/rustc_middle/src/query/mod.rs
@@ -527,7 +527,7 @@ rustc_queries! {
         }
     }
 
-    query mir_generator_witnesses(key: DefId) -> &'tcx mir::GeneratorLayout<'tcx> {
+    query mir_generator_witnesses(key: DefId) -> &'tcx Option<mir::GeneratorLayout<'tcx>> {
         arena_cache
         desc { |tcx| "generator witness types for `{}`", tcx.def_path_str(key) }
         cache_on_disk_if { key.is_local() }
diff --git a/compiler/rustc_middle/src/ty/util.rs b/compiler/rustc_middle/src/ty/util.rs
index c32ba3edd5c..eb903ebfd99 100644
--- a/compiler/rustc_middle/src/ty/util.rs
+++ b/compiler/rustc_middle/src/ty/util.rs
@@ -668,10 +668,10 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         def_id: DefId,
     ) -> impl Iterator<Item = ty::EarlyBinder<Ty<'tcx>>> {
-        let generator_layout = &self.mir_generator_witnesses(def_id);
+        let generator_layout = self.mir_generator_witnesses(def_id);
         generator_layout
-            .field_tys
-            .iter()
+            .as_ref()
+            .map_or_else(|| [].iter(), |l| l.field_tys.iter())
             .filter(|decl| !decl.ignore_for_traits)
             .map(|decl| ty::EarlyBinder(decl.ty))
     }