3 files changed, 60 insertions, 52 deletions
diff --git a/compiler/rustc_middle/src/lib.rs b/compiler/rustc_middle/src/lib.rs
index aadaca18326..80762e3e5c1 100644
--- a/compiler/rustc_middle/src/lib.rs
+++ b/compiler/rustc_middle/src/lib.rs
@@ -35,6 +35,7 @@
 #![feature(const_type_name)]
 #![feature(discriminant_kind)]
 #![feature(coroutines)]
+#![feature(stmt_expr_attributes)]
 #![feature(if_let_guard)]
 #![feature(inline_const)]
 #![feature(iter_from_coroutine)]
diff --git a/compiler/rustc_middle/src/ty/closure.rs b/compiler/rustc_middle/src/ty/closure.rs
index 11167515b7c..b66c664e6ae 100644
--- a/compiler/rustc_middle/src/ty/closure.rs
+++ b/compiler/rustc_middle/src/ty/closure.rs
@@ -422,49 +422,53 @@ pub fn analyze_coroutine_closure_captures<'a, 'tcx: 'a, T>(
     child_captures: impl IntoIterator<Item = &'a CapturedPlace<'tcx>>,
     mut for_each: impl FnMut((usize, &'a CapturedPlace<'tcx>), (usize, &'a CapturedPlace<'tcx>)) -> T,
 ) -> impl Iterator<Item = T> + Captures<'a> + Captures<'tcx> {
-    std::iter::from_coroutine(move || {
-        let mut child_captures = child_captures.into_iter().enumerate().peekable();
-
-        // One parent capture may correspond to several child captures if we end up
-        // refining the set of captures via edition-2021 precise captures. We want to
-        // match up any number of child captures with one parent capture, so we keep
-        // peeking off this `Peekable` until the child doesn't match anymore.
-        for (parent_field_idx, parent_capture) in parent_captures.into_iter().enumerate() {
-            // Make sure we use every field at least once, b/c why are we capturing something
-            // if it's not used in the inner coroutine.
-            let mut field_used_at_least_once = false;
-
-            // A parent matches a child if they share the same prefix of projections.
-            // The child may have more, if it is capturing sub-fields out of
-            // something that is captured by-move in the parent closure.
-            while child_captures.peek().map_or(false, |(_, child_capture)| {
-                child_prefix_matches_parent_projections(parent_capture, child_capture)
-            }) {
-                let (child_field_idx, child_capture) = child_captures.next().unwrap();
-                // This analysis only makes sense if the parent capture is a
-                // prefix of the child capture.
-                assert!(
-                    child_capture.place.projections.len() >= parent_capture.place.projections.len(),
-                    "parent capture ({parent_capture:#?}) expected to be prefix of \
+    std::iter::from_coroutine(
+        #[cfg_attr(not(bootstrap), coroutine)]
+        move || {
+            let mut child_captures = child_captures.into_iter().enumerate().peekable();
+
+            // One parent capture may correspond to several child captures if we end up
+            // refining the set of captures via edition-2021 precise captures. We want to
+            // match up any number of child captures with one parent capture, so we keep
+            // peeking off this `Peekable` until the child doesn't match anymore.
+            for (parent_field_idx, parent_capture) in parent_captures.into_iter().enumerate() {
+                // Make sure we use every field at least once, b/c why are we capturing something
+                // if it's not used in the inner coroutine.
+                let mut field_used_at_least_once = false;
+
+                // A parent matches a child if they share the same prefix of projections.
+                // The child may have more, if it is capturing sub-fields out of
+                // something that is captured by-move in the parent closure.
+                while child_captures.peek().map_or(false, |(_, child_capture)| {
+                    child_prefix_matches_parent_projections(parent_capture, child_capture)
+                }) {
+                    let (child_field_idx, child_capture) = child_captures.next().unwrap();
+                    // This analysis only makes sense if the parent capture is a
+                    // prefix of the child capture.
+                    assert!(
+                        child_capture.place.projections.len()
+                            >= parent_capture.place.projections.len(),
+                        "parent capture ({parent_capture:#?}) expected to be prefix of \
                     child capture ({child_capture:#?})"
-                );
+                    );
 
-                yield for_each(
-                    (parent_field_idx, parent_capture),
-                    (child_field_idx, child_capture),
-                );
+                    yield for_each(
+                        (parent_field_idx, parent_capture),
+                        (child_field_idx, child_capture),
+                    );
 
-                field_used_at_least_once = true;
-            }
+                    field_used_at_least_once = true;
+                }
 
-            // Make sure the field was used at least once.
-            assert!(
-                field_used_at_least_once,
-                "we captured {parent_capture:#?} but it was not used in the child coroutine?"
-            );
-        }
-        assert_eq!(child_captures.next(), None, "leftover child captures?");
-    })
+                // Make sure the field was used at least once.
+                assert!(
+                    field_used_at_least_once,
+                    "we captured {parent_capture:#?} but it was not used in the child coroutine?"
+                );
+            }
+            assert_eq!(child_captures.next(), None, "leftover child captures?");
+        },
+    )
 }
 
 fn child_prefix_matches_parent_projections(
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 7dbe59e132d..45fa5e8f7ca 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -1284,20 +1284,23 @@ impl<'tcx> TyCtxt<'tcx> {
         self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
 
         let definitions = &self.untracked.definitions;
-        std::iter::from_coroutine(|| {
-            let mut i = 0;
-
-            // Recompute the number of definitions each time, because our caller may be creating
-            // new ones.
-            while i < { definitions.read().num_definitions() } {
-                let local_def_index = rustc_span::def_id::DefIndex::from_usize(i);
-                yield LocalDefId { local_def_index };
-                i += 1;
-            }
+        std::iter::from_coroutine(
+            #[cfg_attr(not(bootstrap), coroutine)]
+            || {
+                let mut i = 0;
+
+                // Recompute the number of definitions each time, because our caller may be creating
+                // new ones.
+                while i < { definitions.read().num_definitions() } {
+                    let local_def_index = rustc_span::def_id::DefIndex::from_usize(i);
+                    yield LocalDefId { local_def_index };
+                    i += 1;
+                }
 
-            // Freeze definitions once we finish iterating on them, to prevent adding new ones.
-            definitions.freeze();
-        })
+                // Freeze definitions once we finish iterating on them, to prevent adding new ones.
+                definitions.freeze();
+            },
+        )
     }
 
     pub fn def_path_table(self) -> &'tcx rustc_hir::definitions::DefPathTable {