Rollup merge of #120950 - compiler-errors:miri-async-closurs, r=RalfJung,oli-obk

Fix async closures in CTFE

First commit renames `is_coroutine_or_closure` into `is_closure_like`, because `is_coroutine_or_closure_or_coroutine_closure` seems confusing and long.

Second commit fixes some forgotten cases where we want to handle `TyKind::CoroutineClosure` the same as closures and coroutines.

The test exercises the change to `ValidityVisitor::aggregate_field_path_elem` which is the source of #120946, but not the change to `UsedParamsNeedSubstVisitor`, though I feel like it's not that big of a deal. Let me know if you'd like for me to look into constructing a test for the latter, though I have no idea what it'd look like (we can't assert against `TooGeneric` anywhere?).

Fixes #120946

r? oli-obk cc ``@RalfJung``

1 files changed, 6 insertions, 0 deletions

diff --git a/compiler/rustc_hir/src/def.rs b/compiler/rustc_hir/src/def.rs
index f08ab4bfc09..23943ee28e2 100644
--- a/compiler/rustc_hir/src/def.rs
+++ b/compiler/rustc_hir/src/def.rs
@@ -116,6 +116,12 @@ pub enum DefKind {
     Impl {
         of_trait: bool,
     },
+    /// A closure, coroutine, or coroutine-closure.
+    ///
+    /// These are all represented with the same `ExprKind::Closure` in the AST and HIR,
+    /// which makes it difficult to distinguish these during def collection. Therefore,
+    /// we treat them all the same, and code which needs to distinguish them can match
+    /// or `hir::ClosureKind` or `type_of`.
     Closure,
 }