From a3fdee9a7523a72a5ee72cdb4c1cf3c2cec444bc Mon Sep 17 00:00:00 2001
From: Wim Looman <wim@nemo157.com>
Date: Thu, 4 Oct 2018 20:49:38 +0200
Subject: Change generator trait to use pinning

---
 src/libstd/future.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

(limited to 'src/libstd')

diff --git a/src/libstd/future.rs b/src/libstd/future.rs
index 22900c3067b..d1203be3cf0 100644
--- a/src/libstd/future.rs
+++ b/src/libstd/future.rs
@@ -33,7 +33,9 @@ impl<T: Generator<Yield = ()>> !Unpin for GenFuture<T> {}
 impl<T: Generator<Yield = ()>> Future for GenFuture<T> {
     type Output = T::Return;
     fn poll(self: Pin<&mut Self>, lw: &LocalWaker) -> Poll<Self::Output> {
-        set_task_waker(lw, || match unsafe { Pin::get_unchecked_mut(self).0.resume() } {
+        // Safe because we're !Unpin + !Drop mapping to a ?Unpin value
+        let gen = unsafe { Pin::map_unchecked_mut(self, |s| &mut s.0) };
+        set_task_waker(lw, || match gen.resume() {
             GeneratorState::Yielded(()) => Poll::Pending,
             GeneratorState::Complete(x) => Poll::Ready(x),
         })
-- 
cgit 1.4.1-3-g733a5