Merge pull request #3657 from embassy-rs/waker-unhack

Remove WakerHack for good.

embassy-executor/src/raw/waker.rs

@@ -32,22 +32,11 @@ pub(crate) unsafe fn from_task(p: TaskRef) -> Waker {
 ///
 /// Panics if the waker is not created by the Embassy executor.
 pub fn task_from_waker(waker: &Waker) -> TaskRef {
-    struct WakerHack {
-        data: *const (),
-        vtable: &'static RawWakerVTable,
-    }
-
-    // safety: OK because WakerHack has the same layout as Waker.
-    // This is not really guaranteed because the structs are `repr(Rust)`, it is
-    // indeed the case in the current implementation.
-    // TODO use waker_getters when stable. https://github.com/rust-lang/rust/issues/96992
-    let hack: &WakerHack = unsafe { core::mem::transmute(waker) };
-
     // make sure to compare vtable addresses. Doing `==` on the references
     // will compare the contents, which is slower.
-    if hack.vtable as *const _ != &VTABLE as *const _ {
+    if waker.vtable() as *const _ != &VTABLE as *const _ {
         panic!("Found waker not created by the Embassy executor. `embassy_time::Timer` only works with the Embassy executor.")
     }
     // safety: our wakers are always created with `TaskRef::as_ptr`
-    unsafe { TaskRef::from_ptr(hack.data as *const TaskHeader) }
+    unsafe { TaskRef::from_ptr(waker.data() as *const TaskHeader) }
 }