madsmtm
Fails compiling in `rust-analyzer`
Compile Error in aarch64-apple-darwin target.
proj config:
[package]
name = "untitled"
version = "0.0.0"
edition = "2021"
[dependencies]
objc2 = "0.6.1"
objc2-foundation = "0.3.1"
objc2-app-kit = "0.3.1"
objc2-0.6.1 example code:
#![deny(unsafe_op_in_unsafe_fn)]
use std::cell::OnceCell;
use objc2::rc::Retained;
use objc2::runtime::ProtocolObject;
use objc2::{define_class, msg_send, DefinedClass, MainThreadOnly};
use objc2_app_kit::{
NSApplication, NSApplicationActivationPolicy, NSApplicationDelegate, NSAutoresizingMaskOptions,
NSBackingStoreType, NSColor, NSFont, NSTextAlignment, NSTextField, NSWindow, NSWindowDelegate,
NSWindowStyleMask,
};
use objc2_foundation::{
ns_string, MainThreadMarker, NSNotification, NSObject, NSObjectProtocol, NSPoint, NSRect,
NSSize,
};
#[derive(Debug, Default)]
struct AppDelegateIvars {
window: OnceCell<Retained<NSWindow>>,
}
define_class!(
// SAFETY:
// - The superclass NSObject does not have any subclassing requirements.
// - `Delegate` does not implement `Drop`.
#[unsafe(super = NSObject)]
#[thread_kind = MainThreadOnly]
#[ivars = AppDelegateIvars]
struct Delegate;
// SAFETY: `NSObjectProtocol` has no safety requirements.
unsafe impl NSObjectProtocol for Delegate {}
// SAFETY: `NSApplicationDelegate` has no safety requirements.
unsafe impl NSApplicationDelegate for Delegate {
// SAFETY: The signature is correct.
#[unsafe(method(applicationDidFinishLaunching:))]
fn did_finish_launching(&self, notification: &NSNotification) {
let mtm = self.mtm();
let app = unsafe { notification.object() }
.unwrap()
.downcast::<NSApplication>()
.unwrap();
let text_field = unsafe {
let text_field = NSTextField::labelWithString(ns_string!("Hello, World!"), mtm);
text_field.setFrame(NSRect::new(
NSPoint::new(5.0, 100.0),
NSSize::new(290.0, 100.0),
));
text_field.setTextColor(Some(&NSColor::colorWithSRGBRed_green_blue_alpha(
0.0, 0.5, 0.0, 1.0,
)));
text_field.setAlignment(NSTextAlignment::Center);
text_field.setFont(Some(&NSFont::systemFontOfSize(45.0)));
text_field.setAutoresizingMask(
NSAutoresizingMaskOptions::ViewWidthSizable
| NSAutoresizingMaskOptions::ViewHeightSizable,
);
text_field
};
// SAFETY: We disable releasing when closed below.
let window = unsafe {
NSWindow::initWithContentRect_styleMask_backing_defer(
NSWindow::alloc(mtm),
NSRect::new(NSPoint::new(0.0, 0.0), NSSize::new(300.0, 300.0)),
NSWindowStyleMask::Titled
| NSWindowStyleMask::Closable
| NSWindowStyleMask::Miniaturizable
| NSWindowStyleMask::Resizable,
NSBackingStoreType::Buffered,
false,
)
};
// SAFETY: Disable auto-release when closing windows.
// This is required when creating `NSWindow` outside a window
// controller.
unsafe { window.setReleasedWhenClosed(false) };
// Set various window properties.
window.setTitle(ns_string!("A window"));
let view = window.contentView().expect("window must have content view");
unsafe { view.addSubview(&text_field) };
window.center();
unsafe { window.setContentMinSize(NSSize::new(300.0, 300.0)) };
window.setDelegate(Some(ProtocolObject::from_ref(self)));
// Show the window.
window.makeKeyAndOrderFront(None);
// Store the window in the delegate.
self.ivars().window.set(window).unwrap();
app.setActivationPolicy(NSApplicationActivationPolicy::Regular);
// Activate the application.
// Required when launching unbundled (as is done with Cargo).
#[allow(deprecated)]
app.activateIgnoringOtherApps(true);
}
}
// SAFETY: `NSWindowDelegate` has no safety requirements.
unsafe impl NSWindowDelegate for Delegate {
#[unsafe(method(windowWillClose:))]
fn window_will_close(&self, _notification: &NSNotification) {
// Quit the application when the window is closed.
unsafe { NSApplication::sharedApplication(self.mtm()).terminate(None) };
}
}
);
impl Delegate {
fn new(mtm: MainThreadMarker) -> Retained<Self> {
let this = Self::alloc(mtm).set_ivars(AppDelegateIvars::default());
// SAFETY: The signature of `NSObject`'s `init` method is correct.
unsafe { msg_send![super(this), init] }
}
}
fn main() {
let mtm = MainThreadMarker::new().unwrap();
let app = NSApplication::sharedApplication(mtm);
let delegate = Delegate::new(mtm);
app.setDelegate(Some(ProtocolObject::from_ref(&*delegate)));
app.run();
}
compile error:
error[E0200]: the trait `NSObjectProtocol` requires an `unsafe impl` declaration
--> src/main.rs:22:1
|
22 | / define_class!(
... |
113 | | );
| |_^
|
= note: the trait `NSObjectProtocol` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
= note: this error originates in the macro `$crate::__define_class_output_impls` which comes from the expansion of the macro `define_class` (in Nightly builds, run with -Z macro-backtrace for more info)
help: add `unsafe` to this trait implementation
--> /Users/username/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/objc2-0.6.1/src/macros/define_class.rs:862:9
|
862 | unsafe impl $protocol for $for {}
| ++++++
The same problem occurs in all unsafe implementations of the define_class! macro.
Thanks.
Hmm. I copied your exact example and I could not reproduce your error. I'm on an m1 mac, macOS 15.5, xcode 26 beta (but the non-beta should also work fine).
Ok, Reinstalling Rust solved the problem for me, probably a cache issue.
2025年7月20日 01:24，simlay @.***> 写道：
simlay left a comment (madsmtm/objc2#771) https://github.com/madsmtm/objc2/issues/771#issuecomment-3092467246 Hmm. I copied your exact example and I could not reproduce your error. I'm on an m1 mac, macOS 15.5, xcode 26 beta (but the non-beta should also work fine).
— Reply to this email directly, view it on GitHub https://github.com/madsmtm/objc2/issues/771#issuecomment-3092467246, or unsubscribe https://github.com/notifications/unsubscribe-auth/ANUJDBANBA23DHCYKRQDSGL3JJ5MLAVCNFSM6AAAAACB4QXRYKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTAOJSGQ3DOMRUGY. You are receiving this because you authored the thread.
Yeah, I've seen this kind of issue when using rust-analyzer before. Probably due to our (very) weird macros. I'll keep it open in case I get around to investigating it further at some point.
