crash on macOS 10.14.2 (18C54) at debug_assert!(backend.is_current());

[TakWolf]

/glium-0.23.0/src/context/mod.rs:647:17

I use edition = "2018" and glium = "0.23.0"

It seems that unsafe { backend.make_current() }; not effect.

full stacks:

/Users/takwolf/.cargo/bin/cargo run --color=always --package foo --bin foo
   Compiling khronos_api v3.0.0
   Compiling cfg-if v0.1.6
   Compiling core-foundation-sys v0.6.2
   Compiling libc v0.2.47
   Compiling xml-rs v0.8.0
   Compiling foreign-types-shared v0.1.1
   Compiling bitflags v1.0.4
   Compiling block v0.1.6
   Compiling autocfg v0.1.2
   Compiling lazy_static v1.2.0
   Compiling void v1.0.2
   Compiling rustc-demangle v0.1.13
   Compiling fnv v1.0.6
   Compiling log v0.4.6
   Compiling foreign-types v0.3.2
   Compiling unreachable v1.0.0
   Compiling backtrace v0.3.13
   Compiling smallvec v0.6.8
   Compiling core-foundation v0.6.3
   Compiling malloc_buf v0.0.6
   Compiling shared_library v0.1.9
   Compiling objc v0.2.5
   Compiling gl_generator v0.10.0
   Compiling core-graphics v0.17.3
   Compiling cocoa v0.18.4
   Compiling gleam v0.6.8
   Compiling glutin v0.19.0
   Compiling glium v0.23.0
   Compiling winit v0.18.1
   Compiling cgl v0.2.3
   Compiling foo v0.1.0 (/Users/takwolf/Develop/workspace/foo)
warning: unused variable: `event`
  --> src/main.rs:27:34
   |
27 |         events_loop.poll_events(|event| {
   |                                  ^^^^^ help: consider using `_event` instead
   |
   = note: #[warn(unused_variables)] on by default

    Finished dev [unoptimized + debuginfo] target(s) in 52.49s
     Running `target/debug/foo`
thread 'main' panicked at 'assertion failed: backend.is_current()', /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/context/mod.rs:647:17
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39
   1: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:70
   2: std::panicking::default_hook::{{closure}}
             at src/libstd/sys_common/backtrace.rs:58
             at src/libstd/panicking.rs:200
   3: std::panicking::default_hook
             at src/libstd/panicking.rs:215
   4: <std::panicking::begin_panic::PanicPayload<A> as core::panic::BoxMeUp>::get
             at src/libstd/panicking.rs:478
   5: core::ptr::swap_nonoverlapping_bytes
             at /rustc/7164a9f151a56316a382d8bc2b15ccf373e129ca/src/libstd/panicking.rs:412
   6: glium::context::Context::new::{{closure}}
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/context/mod.rs:647
   7: glium::context::default_debug_callback::{{closure}}
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/context/mod.rs:951
   8: <glium::version::Api as core::cmp::PartialEq>::eq
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/context/mod.rs:217
   9: glium::backend::glutin::Display::new_inner
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/backend/glutin/mod.rs:115
  10: <&'b str as core::str::pattern::Pattern<'a>>::into_searcher
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/backend/glutin/mod.rs:94
  11: <&'b str as core::str::pattern::Pattern<'a>>::into_searcher
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/backend/glutin/mod.rs:79
  12: <&'b str as core::str::pattern::Pattern<'a>>::into_searcher
             at /Users/takwolf/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/glium-0.23.0/src/backend/glutin/mod.rs:71
  13: foo::main
             at src/main.rs:17
  14: std::rt::lang_start::{{closure}}
             at /rustc/7164a9f151a56316a382d8bc2b15ccf373e129ca/src/libstd/rt.rs:64
  15: std::panicking::try::do_call
             at src/libstd/rt.rs:49
             at src/libstd/panicking.rs:297
  16: panic_unwind::dwarf::eh::read_encoded_pointer
             at src/libpanic_unwind/lib.rs:92
  17: <std::panicking::begin_panic::PanicPayload<A> as core::panic::BoxMeUp>::get
             at src/libstd/panicking.rs:276
             at src/libstd/panic.rs:388
             at src/libstd/rt.rs:48
  18: std::rt::lang_start
             at /rustc/7164a9f151a56316a382d8bc2b15ccf373e129ca/src/libstd/rt.rs:64
  19: foo::main

Process finished with exit code 101

source code is:

use glium::{
    glutin:: {
        EventsLoop,
        WindowBuilder,
        ContextBuilder,
    },
    Display,
    Surface,
};

fn main() {
    let mut events_loop = EventsLoop::new();
    let window_builder = WindowBuilder::new()
        .with_dimensions((800.0, 600.0).into())
        .with_resizable(false);
    let context_builder = ContextBuilder::new();
    let display = Display::new(window_builder, context_builder, &events_loop).unwrap();

    let running = true;
    while running {

        let mut target = display.draw();
        target.clear_color(0.0, 0.0, 1.0, 1.0);
        target.finish().unwrap();
        
        events_loop.poll_events(|event| {

        });

    }

}

[TakWolf]

https://developer.apple.com/macos/whats-new/#deprecationofopenglandopencl

[OtaK]

The deprecation seems unrelated, seems it's related to glutin's make_current or is_current methods of the Context.

In the meantime you can compile with --release, the debug assertion will compile away and it seems to work perfectly well. Can it be a race condition on the time the context becomes current and when the assertion is performed?

Can you give us a bit a guidance here @mitchmindtree?

[michael-p]

Seems that the root cause of this is now fixed in Glutin 0.20.0 (Changelog, so once Glium upgrades that dependency this should be ok.

[TakWolf]

The upstream library glutin have finished this.

Please update glium to 0.24.0

I will close this issues.

Please see:
https://github.com/rust-windowing/glutin/blob/v0.20.0/CHANGELOG.md#version-0200-2019-03-09
rust-windowing/glutin#1099