gpui: Entire app freezes when opening a new window from a popup window

[hackerbirds]

Summary

On macOS, GPUI apps freeze when opening a new window from a PopUp window.

I did not test other platforms.

Here is minimal code that reproduce the issue. Pressing enter from a PopUp window will immediately freeze the app:

use gpui::*;

actions!(actions, [OpenNewWindow]);

fn main() {
    let app = Application::new();

    app.run(move |cx| {
        cx.bind_keys([gpui::KeyBinding::new("enter", OpenNewWindow, None)]);

        cx.on_action(|&OpenNewWindow, cx| {
            println!("Opening new window");
            cx.open_window(WindowOptions::default(), |_window, cx| {
                cx.new(|_cx| EmptyView)
            })
            .unwrap();
        });

        let popup_window_options = WindowOptions {
            // ! NOTE: Anything other than `WindowKind::PopUp` works!
            kind: WindowKind::PopUp,
            ..Default::default()
        };

        cx.open_window(popup_window_options, |_window, cx| cx.new(|_cx| EmptyView))
            .unwrap();
    });
}

Here is some stack trace I got from force quitting the app which could help. Looks like there might be a deadlock of some kind:

Lengthy stack trace

Heaviest stack for the main thread of the target process:
  11  start + 7184 (dyld + 36180) [0x180c1dd54]
  11  main + 36 (zed-popup-freeze + 14844) [0x10487f9fc]
  11  std::rt::lang_start::h877cca2d8777ca07 + 84 (rt.rs:205,5 in zed-popup-freeze + 32228) [0x104883de4]
  11  std::rt::lang_start_internal::hdb28e94b6865fa11 + 940 (zed-popup-freeze + 8419944) [0x105083a68]
  11  std::rt::lang_start::_$u7b$$u7b$closure$u7d$$u7d$::hbdc3e835ebf1b6fd + 28 (rt.rs:206,18 in zed-popup-freeze + 32268) [0x104883e0c]
  11  std::sys::backtrace::__rust_begin_short_backtrace::hfc0d45751c9653af + 24 (backtrace.rs:158,18 in zed-popup-freeze + 22796) [0x10488190c]
  11  core::ops::function::FnOnce::call_once::h017c641f418d3ad9 + 20 (function.rs:253,5 in zed-popup-freeze + 23364) [0x104881b44]
  11  zed_popup_freeze::main::h8f0c702f8147536a + 28 (main.rs:8,9 in zed-popup-freeze + 14068) [0x10487f6f4]
  11  gpui::app::Application::run::h8862b4115355e216 + 536 (app.rs:180,18 in zed-popup-freeze + 33172) [0x104884194]
  11  _$LT$gpui..platform..mac..platform..MacPlatform$u20$as$u20$gpui..platform..Platform$GT$::run::h7b28914573ca7173 + 1628 (zed-popup-freeze + 1340676) [0x1049c3504]
  11  _$LT$$BP$mut$u20$objc..runtime..Object$u20$as$u20$cocoa..appkit..NSApplication$GT$::run::h456d9166a7f8e4ee + 336 (zed-popup-freeze + 6982640) [0x104f24bf0]
  11  objc::message::platform::send_unverified::hde956cac3c5b1792 + 140 (zed-popup-freeze + 7047472) [0x104f34930]
  11  _$LT$$LP$$RP$$u20$as$u20$objc..message..MessageArguments$GT$::invoke::h96dc824aaf35ad0e + 72 (zed-popup-freeze + 7050404) [0x104f354a4]
  11  -[NSApplication run] + 408 (AppKit + 100264) [0x1854867a8]
  11  -[NSApplication _handleEvent:] + 60 (AppKit + 5775180) [0x1859eff4c]
  11  -[NSApplication(NSEventRouting) sendEvent:] + 716 (AppKit + 11454568) [0x185f5a868]
  11  -[NSWindow(NSEventRouting) sendEvent:] + 372 (AppKit + 14368348) [0x186221e5c]
  11  -[NSWindow(NSEventRouting) _reallySendEvent:isDelayedEvent:] + 300 (AppKit + 14369548) [0x18622230c]
  11  gpui::platform::mac::window::handle_key_down::h8e6d97937a5f64de + 60 (zed-popup-freeze + 1489992) [0x1049e7c48]
  11  gpui::platform::mac::window::handle_key_event::ha9e82103abce615a + 1152 (zed-popup-freeze + 1491228) [0x1049e811c]
  11  gpui::platform::mac::window::handle_key_event::_$u7b$$u7b$closure$u7d$$u7d$::h12b9bc28638b2077 + 380 (zed-popup-freeze + 1495228) [0x1049e90bc]
  11  _$LT$alloc..boxed..Box$LT$F$C$A$GT$$u20$as$u20$core..ops..function..FnMut$LT$Args$GT$$GT$::call_mut::h8c155216a7d0703d + 68 (zed-popup-freeze + 3785500) [0x104c1831c]
  11  gpui::window::Window::new::_$u7b$$u7b$closure$u7d$$u7d$::h0afae544cd794eb8 + 96 (zed-popup-freeze + 1684320) [0x104a17360]
  11  gpui::window::AnyWindowHandle::update::h1d4720baaff0877f + 52 (zed-popup-freeze + 1729016) [0x104a221f8]
  11  _$LT$gpui..app..async_context..AsyncApp$u20$as$u20$gpui..AppContext$GT$::update_window::hcbd3ff7e7f086f1f + 532 (zed-popup-freeze + 2653632) [0x104b03dc0]
  11  _$LT$gpui..app..App$u20$as$u20$gpui..AppContext$GT$::update_window::h5aa1893ca2de8e76 + 40 (zed-popup-freeze + 2753352) [0x104b1c348]
  11  gpui::app::App::update_window_id::h9e57b6ffb2f52bff + 80 (zed-popup-freeze + 2691132) [0x104b0d03c]
  11  gpui::app::App::update::he39ff219153bbe77 + 116 (zed-popup-freeze + 2680564) [0x104b0a6f4]
  11  gpui::app::App::update_window_id::_$u7b$$u7b$closure$u7d$$u7d$::h469a640fb1759e52 + 828 (zed-popup-freeze + 2708704) [0x104b114e0]
  11  gpui::window::Window::new::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h5b44c874037fef8b + 80 (zed-popup-freeze + 1684476) [0x104a173fc]
  11  gpui::window::Window::dispatch_event::h042b933f711bdb21 + 2312 (zed-popup-freeze + 1738660) [0x104a247a4]
  11  gpui::window::Window::dispatch_key_event::h4694442ba508bb8f + 3392 (zed-popup-freeze + 1715752) [0x104a1ee28]
  11  gpui::window::Window::dispatch_action_on_node::hc07668fb15829794 + 1804 (zed-popup-freeze + 1723876) [0x104a20de4]
  11  gpui::app::App::on_action::_$u7b$$u7b$closure$u7d$$u7d$::h6b455c3bd622e887 + 160 (app.rs:1703,21 in zed-popup-freeze + 41952) [0x1048863e0]
  11  zed_popup_freeze::main::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h9f976aa2ad8ccd0e + 88 (main.rs:13,16 in zed-popup-freeze + 19864) [0x104880d98]
  11  gpui::app::App::open_window::hd56e24ecf92aa54a + 60 (app.rs:948,14 in zed-popup-freeze + 33632) [0x104884360]
  11  gpui::app::App::update::h514a53a8fa61f7f6 + 124 (app.rs:761,22 in zed-popup-freeze + 40664) [0x104885ed8]
  11  gpui::app::App::open_window::_$u7b$$u7b$closure$u7d$$u7d$::hc7fcff924c50ebb5 + 336 (app.rs:951,19 in zed-popup-freeze + 35420) [0x104884a5c]
  11  gpui::window::Window::new::hd1d114e6a94d5848 + 804 (zed-popup-freeze + 1672384) [0x104a144c0]
  11  _$LT$gpui..platform..mac..platform..MacPlatform$u20$as$u20$gpui..platform..Platform$GT$::open_window::he8f131be8d7b58cd + 388 (zed-popup-freeze + 1345600) [0x1049c4840]
  11  gpui::platform::mac::window::MacWindow::open::hcefe09daf098d6d6 + 14720 (zed-popup-freeze + 1441572) [0x1049dbf24]
  11  _$LT$$BP$mut$u20$objc..runtime..Object$u20$as$u20$cocoa..appkit..NSWindow$GT$::makeKeyAndOrderFront_::hdac240509c4787bf + 356 (zed-popup-freeze + 6996968) [0x104f283e8]
  11  objc::message::platform::send_unverified::h58016f96ee3655bf + 152 (zed-popup-freeze + 7046292) [0x104f34494]
  11  _$LT$$LP$A$C$$RP$$u20$as$u20$objc..message..MessageArguments$GT$::invoke::h4648719283251d68 + 96 (zed-popup-freeze + 7031900) [0x104f30c5c]
  11  -[NSWindow makeKeyAndOrderFront:] + 24 (AppKit + 13708272) [0x186180bf0]
  11  -[NSWindow _makeKeyRegardlessOfVisibility] + 56 (AppKit + 617976) [0x185504df8]
  11  -[NSWindow makeKeyWindow] + 160 (AppKit + 618172) [0x185504ebc]
  11  -[NSWindow _changeKeyAndMainLimitedOK:] + 624 (AppKit + 13734248) [0x186187168]
  11  -[NSWindow becomeKeyWindow] + 832 (AppKit + 791908) [0x18552f564]
  11  -[NSNotificationCenter postNotificationName:object:userInfo:] + 88 (Foundation + 10535688) [0x18327b308]
  11  _CFXNotificationPost + 740 (CoreFoundation + 216988) [0x181059f9c]
  11  _CFXRegistrationPost + 436 (CoreFoundation + 765560) [0x1810dfe78]
  11  ___CFXRegistrationPost_block_invoke + 92 (CoreFoundation + 765748) [0x1810dff34]
  11  __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148 (CoreFoundation + 353412) [0x18107b484]
  11  gpui::platform::mac::window::window_did_change_key_status::hfb3865db1f8c4fc6 + 972 (zed-popup-freeze + 1502968) [0x1049eaef8]
  11  objc::message::platform::send_unverified::hcab4ec54393c72dd + 140 (zed-popup-freeze + 7150480) [0x104f4db90]
  11  _$LT$$LP$$RP$$u20$as$u20$objc..message..MessageArguments$GT$::invoke::h895fd4df7c773b27 + 72 (zed-popup-freeze + 7178396) [0x104f5489c]
  11  -[NSWindow resignKeyWindow] + 620 (AppKit + 807560) [0x185533288]
  11  -[NSNotificationCenter postNotificationName:object:userInfo:] + 88 (Foundation + 10535688) [0x18327b308]
  11  _CFXNotificationPost + 740 (CoreFoundation + 216988) [0x181059f9c]
  11  _CFXRegistrationPost + 436 (CoreFoundation + 765560) [0x1810dfe78]
  11  ___CFXRegistrationPost_block_invoke + 92 (CoreFoundation + 765748) [0x1810dff34]
  11  __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148 (CoreFoundation + 353412) [0x18107b484]
  11  gpui::platform::mac::window::window_did_change_key_status::hfb3865db1f8c4fc6 + 156 (zed-popup-freeze + 1502152) [0x1049eabc8]
  11  lock_api::mutex::Mutex$LT$R$C$T$GT$::lock::hee67da89b642bcbe + 28 (zed-popup-freeze + 4002064) [0x104c4d110]
  11  _$LT$parking_lot..raw_mutex..RawMutex$u20$as$u20$lock_api..mutex..RawMutex$GT$::lock::hebed15d28f2aeb5e + 116 (zed-popup-freeze + 1907152) [0x104a4d9d0]
  11  parking_lot::raw_mutex::RawMutex::lock_slow::h4f28ee6c8d310c17 + 348 (zed-popup-freeze + 8710212) [0x1050ca844]
  11  parking_lot_core::parking_lot::park::hbdfbfea7aed3be99 + 272 (zed-popup-freeze + 8182288) [0x105049a10]
  11  parking_lot_core::parking_lot::park::_$u7b$$u7b$closure$u7d$$u7d$::hff5b0b2cae44f063 + 724 (zed-popup-freeze + 8191080) [0x10504bc68]
  11  _$LT$parking_lot_core..thread_parker..imp..ThreadParker$u20$as$u20$parking_lot_core..thread_parker..ThreadParkerT$GT$::park::h6a83654e8c61b04b + 256 (zed-popup-freeze + 8209760) [0x105050560]
  11  __psynch_cvwait + 8 (libsystem_kernel.dylib + 17656) [0x180fa64f8]
 *11  psynch_cvcontinue + 0 (pthread + 18508) [0xfffffe000c09f6dc]


Process:          zed-popup-freeze [32315]
UUID:             5BCDBD9E-A738-3DC8-94DA-C1A205A49EC0
Path:             /Users/USER/*/zed-popup-freeze
Codesigning ID:   zed_popup_freeze-425fdf267a8e621b
Shared Cache:     B69FF43C-DBFD-3FB1-B4FE-A8FE32EA1062 slid base address 0x180b0c000, slide 0xb0c000 (System Primary)
Architecture:     arm64
Responsible:      Electron (VSCodium) [951]
Memory Limit:     0MB
Jetsam Priority:  180
Footprint:        71.89 MB
Time Since Fork:  37s
Num samples:      11 (1-11)
CPU Time:         0.004s (10.6M cycles, 9.5M instructions, 1.11c/i)
Num threads:      6
Note:             3 idle work queue threads omitted

  Thread 0x41551    DispatchQueue "com.apple.main-thread"(1)    Thread name "main"    11 samples (1-11)    priority 46 (base 46)    last ran 34.367s ago
  <thread QoS user interactive (requested user interactive), process unclamped, jetsam priority 180 (requested 180, assertion 0), process memory limit 0MB, process received importance donation from WindowServer [404], IO tier 0>
  11  start + 7184 (dyld + 36180) [0x180c1dd54] 1-11
    11  main + 36 (zed-popup-freeze + 14844) [0x10487f9fc] 1-11
      11  std::rt::lang_start::h877cca2d8777ca07 + 84 (rt.rs:205,5 in zed-popup-freeze + 32228) [0x104883de4] 1-11
        11  std::rt::lang_start_internal::hdb28e94b6865fa11 + 940 (zed-popup-freeze + 8419944) [0x105083a68] 1-11
          11  std::rt::lang_start::_$u7b$$u7b$closure$u7d$$u7d$::hbdc3e835ebf1b6fd + 28 (rt.rs:206,18 in zed-popup-freeze + 32268) [0x104883e0c] 1-11
            11  std::sys::backtrace::__rust_begin_short_backtrace::hfc0d45751c9653af + 24 (backtrace.rs:158,18 in zed-popup-freeze + 22796) [0x10488190c] 1-11
              11  core::ops::function::FnOnce::call_once::h017c641f418d3ad9 + 20 (function.rs:253,5 in zed-popup-freeze + 23364) [0x104881b44] 1-11
                11  zed_popup_freeze::main::h8f0c702f8147536a + 28 (main.rs:8,9 in zed-popup-freeze + 14068) [0x10487f6f4] 1-11
                  11  gpui::app::Application::run::h8862b4115355e216 + 536 (app.rs:180,18 in zed-popup-freeze + 33172) [0x104884194] 1-11
                    11  _$LT$gpui..platform..mac..platform..MacPlatform$u20$as$u20$gpui..platform..Platform$GT$::run::h7b28914573ca7173 + 1628 (zed-popup-freeze + 1340676) [0x1049c3504] 1-11
                      11  _$LT$$BP$mut$u20$objc..runtime..Object$u20$as$u20$cocoa..appkit..NSApplication$GT$::run::h456d9166a7f8e4ee + 336 (zed-popup-freeze + 6982640) [0x104f24bf0] 1-11
                        11  objc::message::platform::send_unverified::hde956cac3c5b1792 + 140 (zed-popup-freeze + 7047472) [0x104f34930] 1-11
                          11  _$LT$$LP$$RP$$u20$as$u20$objc..message..MessageArguments$GT$::invoke::h96dc824aaf35ad0e + 72 (zed-popup-freeze + 7050404) [0x104f354a4] 1-11
                            11  -[NSApplication run] + 408 (AppKit + 100264) [0x1854867a8] 1-11
                              11  -[NSApplication _handleEvent:] + 60 (AppKit + 5775180) [0x1859eff4c] 1-11
                                11  -[NSApplication(NSEventRouting) sendEvent:] + 716 (AppKit + 11454568) [0x185f5a868] 1-11
                                  11  -[NSWindow(NSEventRouting) sendEvent:] + 372 (AppKit + 14368348) [0x186221e5c] 1-11
                                    11  -[NSWindow(NSEventRouting) _reallySendEvent:isDelayedEvent:] + 300 (AppKit + 14369548) [0x18622230c] 1-11
                                      11  gpui::platform::mac::window::handle_key_down::h8e6d97937a5f64de + 60 (zed-popup-freeze + 1489992) [0x1049e7c48] 1-11
                                        11  gpui::platform::mac::window::handle_key_event::ha9e82103abce615a + 1152 (zed-popup-freeze + 1491228) [0x1049e811c] 1-11
                                          11  gpui::platform::mac::window::handle_key_event::_$u7b$$u7b$closure$u7d$$u7d$::h12b9bc28638b2077 + 380 (zed-popup-freeze + 1495228) [0x1049e90bc] 1-11
                                            11  _$LT$alloc..boxed..Box$LT$F$C$A$GT$$u20$as$u20$core..ops..function..FnMut$LT$Args$GT$$GT$::call_mut::h8c155216a7d0703d + 68 (zed-popup-freeze + 3785500) [0x104c1831c] 1-11
                                              11  gpui::window::Window::new::_$u7b$$u7b$closure$u7d$$u7d$::h0afae544cd794eb8 + 96 (zed-popup-freeze + 1684320) [0x104a17360] 1-11
                                                11  gpui::window::AnyWindowHandle::update::h1d4720baaff0877f + 52 (zed-popup-freeze + 1729016) [0x104a221f8] 1-11
                                                  11  _$LT$gpui..app..async_context..AsyncApp$u20$as$u20$gpui..AppContext$GT$::update_window::hcbd3ff7e7f086f1f + 532 (zed-popup-freeze + 2653632) [0x104b03dc0] 1-11
                                                    11  _$LT$gpui..app..App$u20$as$u20$gpui..AppContext$GT$::update_window::h5aa1893ca2de8e76 + 40 (zed-popup-freeze + 2753352) [0x104b1c348] 1-11
                                                      11  gpui::app::App::update_window_id::h9e57b6ffb2f52bff + 80 (zed-popup-freeze + 2691132) [0x104b0d03c] 1-11
                                                        11  gpui::app::App::update::he39ff219153bbe77 + 116 (zed-popup-freeze + 2680564) [0x104b0a6f4] 1-11
                                                          11  gpui::app::App::update_window_id::_$u7b$$u7b$closure$u7d$$u7d$::h469a640fb1759e52 + 828 (zed-popup-freeze + 2708704) [0x104b114e0] 1-11
                                                            11  gpui::window::Window::new::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h5b44c874037fef8b + 80 (zed-popup-freeze + 1684476) [0x104a173fc] 1-11
                                                              11  gpui::window::Window::dispatch_event::h042b933f711bdb21 + 2312 (zed-popup-freeze + 1738660) [0x104a247a4] 1-11
                                                                11  gpui::window::Window::dispatch_key_event::h4694442ba508bb8f + 3392 (zed-popup-freeze + 1715752) [0x104a1ee28] 1-11
                                                                  11  gpui::window::Window::dispatch_action_on_node::hc07668fb15829794 + 1804 (zed-popup-freeze + 1723876) [0x104a20de4] 1-11
                                                                    11  gpui::app::App::on_action::_$u7b$$u7b$closure$u7d$$u7d$::h6b455c3bd622e887 + 160 (app.rs:1703,21 in zed-popup-freeze + 41952) [0x1048863e0] 1-11
                                                                      11  zed_popup_freeze::main::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h9f976aa2ad8ccd0e + 88 (main.rs:13,16 in zed-popup-freeze + 19864) [0x104880d98] 1-11
                                                                        11  gpui::app::App::open_window::hd56e24ecf92aa54a + 60 (app.rs:948,14 in zed-popup-freeze + 33632) [0x104884360] 1-11
                                                                          11  gpui::app::App::update::h514a53a8fa61f7f6 + 124 (app.rs:761,22 in zed-popup-freeze + 40664) [0x104885ed8] 1-11
                                                                            11  gpui::app::App::open_window::_$u7b$$u7b$closure$u7d$$u7d$::hc7fcff924c50ebb5 + 336 (app.rs:951,19 in zed-popup-freeze + 35420) [0x104884a5c] 1-11
                                                                              11  gpui::window::Window::new::hd1d114e6a94d5848 + 804 (zed-popup-freeze + 1672384) [0x104a144c0] 1-11
                                                                                11  _$LT$gpui..platform..mac..platform..MacPlatform$u20$as$u20$gpui..platform..Platform$GT$::open_window::he8f131be8d7b58cd + 388 (zed-popup-freeze + 1345600) [0x1049c4840] 1-11
                                                                                  11  gpui::platform::mac::window::MacWindow::open::hcefe09daf098d6d6 + 14720 (zed-popup-freeze + 1441572) [0x1049dbf24] 1-11
                                                                                    11  _$LT$$BP$mut$u20$objc..runtime..Object$u20$as$u20$cocoa..appkit..NSWindow$GT$::makeKeyAndOrderFront_::hdac240509c4787bf + 356 (zed-popup-freeze + 6996968) [0x104f283e8] 1-11
                                                                                      11  objc::message::platform::send_unverified::h58016f96ee3655bf + 152 (zed-popup-freeze + 7046292) [0x104f34494] 1-11
                                                                                        11  _$LT$$LP$A$C$$RP$$u20$as$u20$objc..message..MessageArguments$GT$::invoke::h4648719283251d68 + 96 (zed-popup-freeze + 7031900) [0x104f30c5c] 1-11
                                                                                          11  -[NSWindow makeKeyAndOrderFront:] + 24 (AppKit + 13708272) [0x186180bf0] 1-11
                                                                                            11  -[NSWindow _makeKeyRegardlessOfVisibility] + 56 (AppKit + 617976) [0x185504df8] 1-11
                                                                                              11  -[NSWindow makeKeyWindow] + 160 (AppKit + 618172) [0x185504ebc] 1-11
                                                                                                11  -[NSWindow _changeKeyAndMainLimitedOK:] + 624 (AppKit + 13734248) [0x186187168] 1-11
                                                                                                  11  -[NSWindow becomeKeyWindow] + 832 (AppKit + 791908) [0x18552f564] 1-11
                                                                                                    11  -[NSNotificationCenter postNotificationName:object:userInfo:] + 88 (Foundation + 10535688) [0x18327b308] 1-11
                                                                                                      11  _CFXNotificationPost + 740 (CoreFoundation + 216988) [0x181059f9c] 1-11
                                                                                                        11  _CFXRegistrationPost + 436 (CoreFoundation + 765560) [0x1810dfe78] 1-11
                                                                                                          11  ___CFXRegistrationPost_block_invoke + 92 (CoreFoundation + 765748) [0x1810dff34] 1-11
                                                                                                            11  __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148 (CoreFoundation + 353412) [0x18107b484] 1-11
                                                                                                              11  gpui::platform::mac::window::window_did_change_key_status::hfb3865db1f8c4fc6 + 972 (zed-popup-freeze + 1502968) [0x1049eaef8] 1-11
                                                                                                                11  objc::message::platform::send_unverified::hcab4ec54393c72dd + 140 (zed-popup-freeze + 7150480) [0x104f4db90] 1-11
                                                                                                                  11  _$LT$$LP$$RP$$u20$as$u20$objc..message..MessageArguments$GT$::invoke::h895fd4df7c773b27 + 72 (zed-popup-freeze + 7178396) [0x104f5489c] 1-11
                                                                                                                    11  -[NSWindow resignKeyWindow] + 620 (AppKit + 807560) [0x185533288] 1-11
                                                                                                                      11  -[NSNotificationCenter postNotificationName:object:userInfo:] + 88 (Foundation + 10535688) [0x18327b308] 1-11
                                                                                                                        11  _CFXNotificationPost + 740 (CoreFoundation + 216988) [0x181059f9c] 1-11
                                                                                                                          11  _CFXRegistrationPost + 436 (CoreFoundation + 765560) [0x1810dfe78] 1-11
                                                                                                                            11  ___CFXRegistrationPost_block_invoke + 92 (CoreFoundation + 765748) [0x1810dff34] 1-11
                                                                                                                              11  __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148 (CoreFoundation + 353412) [0x18107b484] 1-11
                                                                                                                                11  gpui::platform::mac::window::window_did_change_key_status::hfb3865db1f8c4fc6 + 156 (zed-popup-freeze + 1502152) [0x1049eabc8] 1-11
                                                                                                                                  11  lock_api::mutex::Mutex$LT$R$C$T$GT$::lock::hee67da89b642bcbe + 28 (zed-popup-freeze + 4002064) [0x104c4d110] 1-11
                                                                                                                                    11  _$LT$parking_lot..raw_mutex..RawMutex$u20$as$u20$lock_api..mutex..RawMutex$GT$::lock::hebed15d28f2aeb5e + 116 (zed-popup-freeze + 1907152) [0x104a4d9d0] 1-11
                                                                                                                                      11  parking_lot::raw_mutex::RawMutex::lock_slow::h4f28ee6c8d310c17 + 348 (zed-popup-freeze + 8710212) [0x1050ca844] 1-11
                                                                                                                                        11  parking_lot_core::parking_lot::park::hbdfbfea7aed3be99 + 272 (zed-popup-freeze + 8182288) [0x105049a10] 1-11
                                                                                                                                          11  parking_lot_core::parking_lot::park::_$u7b$$u7b$closure$u7d$$u7d$::hff5b0b2cae44f063 + 724 (zed-popup-freeze + 8191080) [0x10504bc68] 1-11
                                                                                                                                            11  _$LT$parking_lot_core..thread_parker..imp..ThreadParker$u20$as$u20$parking_lot_core..thread_parker..ThreadParkerT$GT$::park::h6a83654e8c61b04b + 256 (zed-popup-freeze + 8209760) [0x105050560] 1-11
                                                                                                                                              11  __psynch_cvwait + 8 (libsystem_kernel.dylib + 17656) [0x180fa64f8] 1-11
                                                                                                                                               *11  psynch_cvcontinue + 0 (pthread + 18508) [0xfffffe000c09f6dc] 1-11

  Thread 0x41563    Thread name "com.apple.NSEventThread"    11 samples (1-11)    priority 46 (base 46)    cpu time 0.003s (7.0M cycles, 7.8M instructions, 0.90c/i)    last ran 0.110s ago
  <thread QoS user interactive (requested user interactive), process unclamped, jetsam priority 180 (requested 180, assertion 0), process memory limit 0MB, process received importance donation from WindowServer [404], IO tier 0>
  11  thread_start + 8 (libsystem_pthread.dylib + 7080) [0x180fe0ba8] 1-11
    11  _pthread_start + 136 (libsystem_pthread.dylib + 27656) [0x180fe5c08] 1-11
      11  _NSEventThread + 184 (AppKit + 720052) [0x18551dcb4] 1-11
        11  _CFRunLoopRunSpecificWithOptions + 532 (CoreFoundation + 1147740) [0x18113d35c] 1-11
          11  __CFRunLoopRun + 1188 (CoreFoundation + 386280) [0x1810834e8] 1-11
            11  __CFRunLoopServiceMachPort + 160 (CoreFoundation + 392080) [0x181084b90] 1-11
              11  mach_msg + 24 (libsystem_kernel.dylib + 4020) [0x180fa2fb4] 1-11
                11  mach_msg_overwrite + 484 (libsystem_kernel.dylib + 39308) [0x180fab98c] 1-11
                  11  mach_msg2_trap + 8 (libsystem_kernel.dylib + 3124) [0x180fa2c34] 1-11
                   *11  ??? (kernel.release.t8132 + 195860) [0xfffffe0008883d14] 1-11

  Thread 0x4156d    Thread name "CVDisplayLink"    11 samples (1-11)    priority 54 (base 54)    cpu time 0.002s (3.6M cycles, 1740.8K instructions, 2.08c/i)
  <process unclamped, jetsam priority 180 (requested 180, assertion 0), process memory limit 0MB, process received importance donation from WindowServer [404], IO tier 0>
  11  thread_start + 8 (libsystem_pthread.dylib + 7080) [0x180fe0ba8] 1-11
    11  _pthread_start + 136 (libsystem_pthread.dylib + 27656) [0x180fe5c08] 1-11
      11  CVDisplayLink::runIOThread() + 500 (CoreVideo + 11300) [0x18b5f4c24] 1-11
        11  CVDisplayLink::waitUntil(unsigned long long) + 336 (CoreVideo + 15164) [0x18b5f5b3c] 1-11
          11  __psynch_cvwait + 8 (libsystem_kernel.dylib + 17656) [0x180fa64f8] 1-11
           *11  psynch_cvcontinue + 0 (pthread + 18508) [0xfffffe000c09f6dc] 1-11

  Binary Images:
           0x10487c000 -        0x10548ffff  zed-popup-freeze (0)                      <5BCDBD9E-A738-3DC8-94DA-C1A205A49EC0>             /Users/USER/*/zed-popup-freeze
           0x180c15000 -        0x180cb3f63  dyld (1330)                               <B50F5A1A-BE81-3068-92E1-3554F2BE478A>             /usr/lib/dyld
           0x180fa2000 -        0x180fde49f  libsystem_kernel.dylib (12377.41.6)       <9FE7C84D-0C2B-363F-BEE5-6FD76D67A227>             /usr/lib/system/libsystem_kernel.dylib
           0x180fdf000 -        0x180febabb  libsystem_pthread.dylib (539)             <E95973B8-824C-361E-ADF4-390747C40897>             /usr/lib/system/libsystem_pthread.dylib
           0x181025000 -        0x18156babf  com.apple.CoreFoundation 6.9 (4109.1.401) <3C4A3ADD-9E48-33DA-82EE-80520E6CBE3B>             /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation
           0x18286f000 -        0x18381225f  com.apple.Foundation 6.9 (4109.1.401)     <00467F1F-216A-36FE-8587-C820C7E0437D>             /System/Library/Frameworks/Foundation.framework/Versions/C/Foundation
           0x18546e000 -        0x186b9ab9f  com.apple.AppKit 6.9 (2685.20.119)        <3C0949BB-E361-369A-80B7-17440EB09E98>             /System/Library/Frameworks/AppKit.framework/Versions/C/AppKit
           0x18b5f2000 -        0x18b675fff  com.apple.CoreVideo 1.8 (726.2)           <D8605842-8C6C-36D7-820D-2132D91E0C06>             /System/Library/Frameworks/CoreVideo.framework/Versions/A/CoreVideo
   *0xfffffe0008854000 - 0xfffffe00091bbfff  kernel.release.t8132 (25.1.0)             <D63F3888-78EC-3973-B4BA-5F51AA6B6573>__TEXT_EXEC  /System/Library/Kernels/kernel.release.t8132
   *0xfffffe000c09ae90 - 0xfffffe000c0a0d27  com.apple.kec.pthread (1)                 <BADB8104-0DD8-3205-A9F0-B8499E5CFAFE>__TEXT_EXEC  /System/Library/Extensions/pthread.kext/Contents/MacOS/pthread

Zed Version and System Specs

N/A

If applicable, attach your Zed.log file to this issue.

No response

[hackerbirds]

I narrowed down the issue to these lines of code:

zed/crates/gpui/src/platform/mac/window.rs

Lines 2018 to 2032 in 1683052

	// When opening a pop-up while the application isn't active, Cocoa sends a spurious
	// `windowDidBecomeKey` message to the previous key window even though that window
	// isn't actually key. This causes a bug if the application is later activated while
	// the pop-up is still open, making it impossible to activate the previous key window
	// even if the pop-up gets closed. The only way to activate it again is to de-activate
	// the app and re-activate it, which is a pretty bad UX.
	// The following code detects the spurious event and invokes `resignKeyWindow`:
	// in theory, we're not supposed to invoke this method manually but it balances out
	// the spurious `becomeKeyWindow` event and helps us work around that bug.
	if selector == sel!(windowDidBecomeKey:) && !is_active {
	unsafe {
	let _: () = msg_send![lock.native_window, resignKeyWindow];
	return;
	}
	}

I have no idea what it's really supposed to do, but removing them fixes the issue.

[miguelraz]

Aha! Great catch!

Thanks for the reproducer! I'll let the eng team know.

[github-actions]

Hi there! Zed development moves fast and a significant number of bugs become outdated. If you can reproduce this bug on the latest stable Zed, please let us know by leaving a comment with the Zed version. If the bug doesn't appear for you anymore, feel free to close the issue yourself; otherwise, the bot will close it in a couple of weeks.
Thanks for your help!

[ssiebert-pg]

I encountered the same deadlock in a different scenario: macOS window state restoration on app startup.

When macOS tries to restore windows from a previous session (NSPersistentUIRestorer), it triggers the same re-entrant window_did_change_key_status deadlock:

NSPersistentUIRestorer restoreStateFromRecords
  → _finishedRestoringWindowsWithZOrder
    → NSWindow becomeKeyWindow
      → gpui::window_did_change_key_status (acquires lock)
        → NSWindow resignKeyWindow
          → gpui::window_did_change_key_status (deadlock - same lock)

Stack trace is nearly identical to the one reported here - the mutex in parking_lot::raw_mutex::RawMutex::lock_slow blocks forever.

Workaround: Disable macOS window restoration before GPUI starts:

#[cfg(target_os = "macos")]
fn disable_window_restoration() {
    use objc::runtime::{NO, YES};
    use objc::{class, msg_send, sel, sel_impl};
    
    unsafe {
        let defaults: *mut objc::runtime::Object =
            msg_send![class!(NSUserDefaults), standardUserDefaults];
        let key1: *mut objc::runtime::Object = 
            msg_send![class!(NSString), stringWithUTF8String: b"NSQuitAlwaysKeepsWindows\0".as_ptr()];
        let key2: *mut objc::runtime::Object = 
            msg_send![class!(NSString), stringWithUTF8String: b"ApplePersistenceIgnoreState\0".as_ptr()];
        let _: () = msg_send![defaults, setBool:NO forKey:key1];
        let _: () = msg_send![defaults, setBool:YES forKey:key2];
    }
}

Call this at the very start of main() before Application::new().

This confirms the root cause is the re-entrant lock issue in window_did_change_key_status, not specific to popup windows.