executor: use WakerHack unconditionally even if `nightly` feature is enabled. (#3528)

This ensures the executor compiles with all recent nightly versions,
including the stable-but-with-nightly-features-enabled xtensa rustc.

2 files changed, 11 insertions, 32 deletions

diff --git a/embassy-executor/src/lib.rs b/embassy-executor/src/lib.rs
index 8e07a8b18..d816539ac 100644
--- a/embassy-executor/src/lib.rs
+++ b/embassy-executor/src/lib.rs
@@ -1,5 +1,4 @@
 #![cfg_attr(not(any(feature = "arch-std", feature = "arch-wasm")), no_std)]
-#![cfg_attr(all(feature = "nightly", not(at_least_2024_09_06)), feature(waker_getters))]
 #![allow(clippy::new_without_default)]
 #![doc = include_str!("../README.md")]
 #![warn(missing_docs)]
diff --git a/embassy-executor/src/raw/waker.rs b/embassy-executor/src/raw/waker.rs
index 30b8cdd4c..d2256adfa 100644
--- a/embassy-executor/src/raw/waker.rs
+++ b/embassy-executor/src/raw/waker.rs
@@ -32,40 +32,20 @@ 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 {
-    let (vtable, data) = {
-        #[cfg(not(feature = "nightly"))]
-        {
-            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) };
-            (hack.vtable, hack.data)
-        }
-
-        #[cfg(feature = "nightly")]
-        {
-            #[cfg(not(at_least_2024_09_06))]
-            {
-                let raw_waker = waker.as_raw();
-                (raw_waker.vtable(), raw_waker.data())
-            }
+    struct WakerHack {
+        data: *const (),
+        vtable: &'static RawWakerVTable,
+    }
 
-            #[cfg(at_least_2024_09_06)]
-            {
-                (waker.vtable(), waker.data())
-            }
-        }
-    };
+    // 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) };
 
-    if vtable != &VTABLE {
+    if hack.vtable != &VTABLE {
         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(data as *const TaskHeader) }
+    unsafe { TaskRef::from_ptr(hack.data as *const TaskHeader) }
 }