Crash when moving Window to background in Example

[seivan]

This sample crashes when running with Metal on macOS Mojave.

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: ()', src/libcore/result.rs:1009:5
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:71
   2: std::panicking::default_hook::{{closure}}
             at src/libstd/sys_common/backtrace.rs:59
             at src/libstd/panicking.rs:211
   3: std::panicking::default_hook
             at src/libstd/panicking.rs:227
   4: <std::panicking::begin_panic::PanicPayload<A> as core::panic::BoxMeUp>::get
             at src/libstd/panicking.rs:491
   5: std::panicking::continue_panic_fmt
             at src/libstd/panicking.rs:398
   6: std::panicking::try::do_call
             at src/libstd/panicking.rs:325
   7: core::char::methods::<impl char>::escape_debug
             at src/libcore/panicking.rs:95
   8: <parking_lot::raw_mutex::RawMutex as lock_api::mutex::RawMutex>::unlock
             at /rustc/9fda7c2237db910e41d6a712e9a2139b352e558b/src/libcore/macros.rs:26
   9: <parking_lot::raw_mutex::RawMutex as lock_api::mutex::RawMutex>::unlock
             at /rustc/9fda7c2237db910e41d6a712e9a2139b352e558b/src/libcore/result.rs:808
  10: core::alloc::Layout::repeat
             at wgpu-native/src/swap_chain.rs:159
  11: wgpu::TextureCopyView::into_native
             at wgpu-rs/src/lib.rs:673
  12: core::ptr::real_drop_in_place
             at /rustc/9fda7c2237db910e41d6a712e9a2139b352e558b/src/libcore/ptr.rs:204
  13: cube::framework::run
             at gfx-examples/src/framework.rs:111
  14: cube::main
             at gfx-examples/src/cube.rs:330
  15: std::rt::lang_start::{{closure}}
             at /rustc/9fda7c2237db910e41d6a712e9a2139b352e558b/src/libstd/rt.rs:74
  16: std::panicking::try::do_call
             at src/libstd/rt.rs:59
             at src/libstd/panicking.rs:310
  17: panic_unwind::dwarf::eh::read_encoded_pointer
             at src/libpanic_unwind/lib.rs:102
  18: <std::panicking::begin_panic::PanicPayload<A> as core::panic::BoxMeUp>::get
             at src/libstd/panicking.rs:289
             at src/libstd/panic.rs:398
             at src/libstd/rt.rs:58
  19: std::rt::lang_start
             at /rustc/9fda7c2237db910e41d6a712e9a2139b352e558b/src/libstd/rt.rs:74
  20: <cube::Vertex as core::clone::Clone>::clone

[kvark]

Thanks for filing the issue!
There isn't proper support here yet for swapchain resizing/recreation/errors.

[seivan]

@kvark Is that an issue in gfx-hal, gfx-examples or WebGPU itself?
I mean as far as I remember, gfx-hal didn't have this issue at all, so it could be the example or WebGPU?

[kvark]

Yes, it's here.

…

On Feb 18, 2019, at 07:33, Seivan Heidari ***@***.***> wrote: @kvark Is that an issue in gfx-hal, gfx-examples or WebGPU itself? I mean as far as I remember, gfx-hal didn't have this issue at all, so it could be the example or WebGPU? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[seivan]

This also happens on iOS but I'm not 100% sure it's related.

thread '<unnamed>' panicked at 'called `Result::unwrap()` on an `Err` value: ()', src/libcore/result.rs:1009:5
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
   1: std::sys_common::backtrace::_print
   2: std::panicking::default_hook::{{closure}}
   3: std::panicking::default_hook
   4: std::panicking::rust_panic_with_hook
   5: std::panicking::continue_panic_fmt
   6: rust_begin_unwind
   7: core::panicking::panic_fmt
   8: core::result::unwrap_failed
   9: <core::result::Result<T, E>>::unwrap
  10: wgpu_swap_chain_present
  11: <wgpu::SwapChainOutput<'a> as core::ops::drop::Drop>::drop
  12: core::ptr::real_drop_in_place

Seems to be a swapchain issue - but I can't tell further.

[seivan]

Resolved in #69
However still limited to N amount of Swapchains (or MTLDrawables returned from a swapchain)