update to work on smol/master

Author: dignifiedquire

src/os/unix/net/datagram.rs

@@ -319,7 +319,8 @@ impl AsRawFd for UnixDatagram {
 
 impl FromRawFd for UnixDatagram {
     unsafe fn from_raw_fd(fd: RawFd) -> UnixDatagram {
-        let datagram = Async::<StdUnixDatagram>::from_raw_fd(fd);
+        let raw = StdUnixDatagram::from_raw_fd(fd);
+        let datagram = Async::<StdUnixDatagram>::new(raw).expect("invalid file descriptor");
         UnixDatagram { watcher: datagram }
     }
 }

src/task/builder.rs

@@ -55,7 +55,7 @@ impl Builder {
         let wrapped = self.build(future);
 
         let task = wrapped.tag.task().clone();
-        let smol_task = smol::Task::spawn(wrapped).detach();
+        let smol_task = smol::Task::spawn(wrapped).into();
 
         Ok(JoinHandle::new(smol_task, task))
     }

src/task/spawn_blocking.rs

@@ -37,6 +37,6 @@ where
 {
     once_cell::sync::Lazy::force(&crate::rt::RUNTIME);
 
-    let handle = smol::Task::blocking(async move { f() }).detach();
+    let handle = smol::Task::blocking(async move { f() }).into();
     JoinHandle::new(handle, Task::new(None))
 }