Properly handle `Pin<&mut dyn* Trait>` receiver in codegen

2 files changed, 62 insertions, 0 deletions

diff --git a/src/test/ui/dyn-star/dispatch-on-pin-mut.rs b/src/test/ui/dyn-star/dispatch-on-pin-mut.rs
new file mode 100644
index 00000000000..8eedff87d0d
--- /dev/null
+++ b/src/test/ui/dyn-star/dispatch-on-pin-mut.rs
@@ -0,0 +1,51 @@
+// build-pass
+// edition:2021
+
+#![feature(dyn_star)]
+//~^ WARN the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
+
+use std::future::Future;
+
+async fn foo(f: dyn* Future<Output = i32>) {
+    println!("value: {}", f.await);
+}
+
+async fn async_main() {
+    foo(Box::pin(async { 1 })).await
+}
+
+// ------------------------------------------------------------------------- //
+// Implementation Details Below...
+
+use std::pin::Pin;
+use std::task::*;
+
+pub fn noop_waker() -> Waker {
+    let raw = RawWaker::new(std::ptr::null(), &NOOP_WAKER_VTABLE);
+
+    // SAFETY: the contracts for RawWaker and RawWakerVTable are upheld
+    unsafe { Waker::from_raw(raw) }
+}
+
+const NOOP_WAKER_VTABLE: RawWakerVTable = RawWakerVTable::new(noop_clone, noop, noop, noop);
+
+unsafe fn noop_clone(_p: *const ()) -> RawWaker {
+    RawWaker::new(std::ptr::null(), &NOOP_WAKER_VTABLE)
+}
+
+unsafe fn noop(_p: *const ()) {}
+
+fn main() {
+    let mut fut = async_main();
+
+    // Poll loop, just to test the future...
+    let waker = noop_waker();
+    let ctx = &mut Context::from_waker(&waker);
+
+    loop {
+        match unsafe { Pin::new_unchecked(&mut fut).poll(ctx) } {
+            Poll::Pending => {}
+            Poll::Ready(()) => break,
+        }
+    }
+}
diff --git a/src/test/ui/dyn-star/dispatch-on-pin-mut.stderr b/src/test/ui/dyn-star/dispatch-on-pin-mut.stderr
new file mode 100644
index 00000000000..a73e3400922
--- /dev/null
+++ b/src/test/ui/dyn-star/dispatch-on-pin-mut.stderr
@@ -0,0 +1,11 @@
+warning: the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/dispatch-on-pin-mut.rs:4:12
+   |
+LL | #![feature(dyn_star)]
+   |            ^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+