Auto merge of #107064 - GuillaumeGomez:rollup-pbgu6r3, r=GuillaumeGomez

Rollup of 5 pull requests

Successful merges:

 - #105977 (Transform async `ResumeTy` in generator transform)
 - #106927 (make `CastError::NeedsDeref` create a `MachineApplicable` suggestion)
 - #106931 (document + UI test `E0208` and make its output more user-friendly)
 - #107027 (Remove extra removal from test path)
 - #107037 (Fix Dominators::rank_partial_cmp to match documentation)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

core/src/future/mod.rs

@@ -112,6 +112,10 @@ pub unsafe fn get_context<'a, 'b>(cx: ResumeTy) -> &'a mut Context<'b> {
     unsafe { &mut *cx.0.as_ptr().cast() }
 }
 
+// FIXME(swatinem): This fn is currently needed to work around shortcomings
+// in type and lifetime inference.
+// See the comment at the bottom of `LoweringContext::make_async_expr` and
+// <https://github.com/rust-lang/rust/issues/104826>.
 #[doc(hidden)]
 #[unstable(feature = "gen_future", issue = "50547")]
 #[inline]

core/src/task/wake.rs

@@ -174,6 +174,7 @@ impl RawWakerVTable {
 /// Currently, `Context` only serves to provide access to a [`&Waker`](Waker)
 /// which can be used to wake the current task.
 #[stable(feature = "futures_api", since = "1.36.0")]
+#[cfg_attr(not(bootstrap), lang = "Context")]
 pub struct Context<'a> {
     waker: &'a Waker,
     // Ensure we future-proof against variance changes by forcing