Change sys::Thread::new to take the thread entry as Box<dyn FnBox() + 'static>̣

src/libstd/sys/windows/thread.rs

@@ -28,7 +28,8 @@ pub struct Thread {
 }
 
 impl Thread {
-    pub unsafe fn new<'a>(stack: usize, p: Box<dyn FnBox() + 'a>)
+    // unsafe: see thread::Builder::spawn_unchecked for safety requirements
+    pub unsafe fn new(stack: usize, p: Box<dyn FnBox()>)
                           -> io::Result<Thread> {
         let p = box p;