Fix a couple more DefKind discrepancies between DefKind::Closure and DefKind::SyntheticCoroutineBody

compiler/rustc_hir/src/def.rs

@@ -287,7 +287,10 @@ impl DefKind {
 
     #[inline]
     pub fn is_fn_like(self) -> bool {
-        matches!(self, DefKind::Fn | DefKind::AssocFn | DefKind::Closure)
+        matches!(
+            self,
+            DefKind::Fn | DefKind::AssocFn | DefKind::Closure | DefKind::SyntheticCoroutineBody
+        )
     }
 
     /// Whether `query get_codegen_attrs` should be used with this definition.

compiler/rustc_mir_transform/src/cross_crate_inline.rs

@@ -24,7 +24,7 @@ fn cross_crate_inlinable(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
 
     // This just reproduces the logic from Instance::requires_inline.
     match tcx.def_kind(def_id) {
-        DefKind::Ctor(..) | DefKind::Closure => return true,
+        DefKind::Ctor(..) | DefKind::Closure | DefKind::SyntheticCoroutineBody => return true,
         DefKind::Fn | DefKind::AssocFn => {}
         _ => return false,
     }

compiler/rustc_symbol_mangling/src/lib.rs

@@ -227,7 +227,11 @@ fn compute_symbol_name<'tcx>(
     // and we want to be sure to avoid any symbol conflicts here.
     let is_globally_shared_function = matches!(
         tcx.def_kind(instance.def_id()),
-        DefKind::Fn | DefKind::AssocFn | DefKind::Closure | DefKind::Ctor(..)
+        DefKind::Fn
+            | DefKind::AssocFn
+            | DefKind::Closure
+            | DefKind::SyntheticCoroutineBody
+            | DefKind::Ctor(..)
     ) && matches!(
         MonoItem::Fn(instance).instantiation_mode(tcx),
         InstantiationMode::GloballyShared { may_conflict: true }

tests/ui/async-await/async-closures/inline-body.rs

@@ -0,0 +1,34 @@
+//@ edition: 2021
+//@ compile-flags: -Zinline-mir
+//@ build-pass
+
+// Ensure that we don't hit a Steal ICE because we forgot to ensure
+// `mir_inliner_callees` for the synthetic by-move coroutine body since
+// its def-id wasn't previously being considered.
+
+#![feature(async_closure, noop_waker)]
+
+use std::future::Future;
+use std::pin::pin;
+use std::task::*;
+
+pub fn block_on<T>(fut: impl Future<Output = T>) -> T {
+    let mut fut = pin!(fut);
+    let ctx = &mut Context::from_waker(Waker::noop());
+
+    loop {
+        match fut.as_mut().poll(ctx) {
+            Poll::Pending => {}
+            Poll::Ready(t) => break t,
+        }
+    }
+}
+
+async fn call_once<T>(f: impl async FnOnce() -> T) -> T {
+    f().await
+}
+
+fn main() {
+    let c = async || {};
+    block_on(call_once(c));
+}