chore: fix nightly CI on linux/ios

Co-authored-by: Mads Marquart <mads@marquart.dk>

src/platform/x11.rs

@@ -81,9 +81,7 @@ pub type XWindow = u32;
 #[inline]
 pub fn register_xlib_error_hook(hook: XlibErrorHook) {
     // Append new hook.
-    unsafe {
+    crate::platform_impl::XLIB_ERROR_HOOKS.lock().unwrap().push(hook);
-        crate::platform_impl::XLIB_ERROR_HOOKS.lock().unwrap().push(hook);
-    }
 }
 
 /// Additional methods on [`ActiveEventLoop`] that are specific to X11.

src/platform_impl/ios/app_state.rs

@@ -147,6 +147,8 @@ impl AppState {
         // must be mut because plain `static` requires `Sync`
         static mut APP_STATE: RefCell<Option<AppState>> = RefCell::new(None);
 
+        #[allow(unknown_lints)] // New lint below
+        #[allow(static_mut_refs)] // TODO: Use `MainThreadBound` instead.
         let mut guard = unsafe { APP_STATE.borrow_mut() };
         if guard.is_none() {
             #[inline(never)]

src/platform_impl/linux/mod.rs

@@ -647,7 +647,7 @@ pub(crate) enum PlatformCustomCursor {
 
 /// Hooks for X11 errors.
 #[cfg(x11_platform)]
-pub(crate) static mut XLIB_ERROR_HOOKS: Mutex<Vec<XlibErrorHook>> = Mutex::new(Vec::new());
+pub(crate) static XLIB_ERROR_HOOKS: Mutex<Vec<XlibErrorHook>> = Mutex::new(Vec::new());
 
 #[cfg(x11_platform)]
 unsafe extern "C" fn x_error_callback(
@@ -658,7 +658,7 @@ unsafe extern "C" fn x_error_callback(
     if let Ok(ref xconn) = *xconn_lock {
         // Call all the hooks.
         let mut error_handled = false;
-        for hook in unsafe { XLIB_ERROR_HOOKS.lock() }.unwrap().iter() {
+        for hook in XLIB_ERROR_HOOKS.lock().unwrap().iter() {
             error_handled |= hook(display as *mut _, event as *mut _);
         }