Triangle example fails (RHEL7)

[xloem]

With current git tip, I see a brief flicker and the application immediately terminates.

cd examples/triangle && "build/triangle"
[Warn] Unable to find layer: VK_LAYER_KHRONOS_validation
[]WGPUFeatureName {
        Depth32FloatStencil8
        TimestampQuery
        PipelineStatisticsQuery
        TextureCompressionBC
        TextureCompressionETC2
        TextureCompressionASTC
        IndirectFirstInstance
        WGPUNativeFeature_PUSH_CONSTANTS
        WGPUNativeFeature_TEXTURE_ADAPTER_SPECIFIC_FORMAT_FEATURES
        WGPUNativeFeature_MULTI_DRAW_INDIRECT
        WGPUNativeFeature_VERTEX_WRITABLE_STORAGE
}
[Warn] Missing extensions: ["VK_KHR_timeline_semaphore"]
X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  149 ()
  Minor opcode of failed request:  4
  Serial number of failed request:  179
  Current serial number in output stream:  185

EDIT: I've found others describing experiencing this issue on the internet, but nothing I find clear yet. They mention unmapped windows and GL. The crash appears to happen in the second call to glfwGetWindowSize. The first call completes fine.

(gdb) bt
#0  0x00007ffff65e5eb0 in XGetWindowAttributes () from /lib64/libX11.so.6
#1  0x000000000041a0ad in _glfwPlatformGetWindowSize (window=0x49ecc0, width=0x7fffffffd24c, height=0x7fffffffd248) at /home/user/src/glfw/src/x11_window.c:2201
#2  0x000000000040f41c in glfwGetWindowSize (handle=0x49ecc0, width=0x7fffffffd24c, height=0x7fffffffd248) at /home/user/src/glfw/src/window.c:551
#3  0x0000000000405386 in main () at /home/user/src/wgpu-native/examples/triangle/main.c:285

EDIT: Here is an xtrace log.

EDIT: I modified the source to select GL as primary backend rather than Vulkan, and experienced the below. Note: the .c line numbers are off because I added extra statements to try to narrow the earlier issue down (it turns out it was triggered after setting the swap chain). I thought I did pass RUST_BACKTRACE=full, even though it complains. I could have made a typo setting the environment variable. :

cargo build 
    Finished dev [unoptimized + debuginfo] target(s) in 0.18s
cd examples/triangle && mkdir -p build && cd build && cmake -DCMAKE_BUILD_TYPE=Debug ..  && cmake --build .
-- Configuring done
-- Generating done
-- Build files have been written to: /home/user/src/wgpu-native/examples/triangle/build
gmake[1]: Entering directory `/shared/src/wgpu-native/examples/triangle/build'
gmake[2]: Entering directory `/shared/src/wgpu-native/examples/triangle/build'
gmake[3]: Entering directory `/shared/src/wgpu-native/examples/triangle/build'
Consolidate compiler generated dependencies of target triangle
gmake[3]: Leaving directory `/shared/src/wgpu-native/examples/triangle/build'
[100%] Built target triangle
gmake[2]: Leaving directory `/shared/src/wgpu-native/examples/triangle/build'
gmake[1]: Leaving directory `/shared/src/wgpu-native/examples/triangle/build'
cd examples/triangle && "build/triangle"
thread '<unnamed>' panicked at 'invalid AdapterId', src/lib.rs:184:5
stack backtrace:
   0: rust_begin_unwind
             at /builddir/build/BUILD/rustc-1.65.0-src/library/std/src/panicking.rs:584:5
   1: core::panicking::panic_fmt
             at /builddir/build/BUILD/rustc-1.65.0-src/library/core/src/panicking.rs:142:14
   2: core::panicking::panic_display
             at /builddir/build/BUILD/rustc-1.65.0-src/library/core/src/panicking.rs:72:5
   3: core::panicking::panic_str
             at /builddir/build/BUILD/rustc-1.65.0-src/library/core/src/panicking.rs:56:5
   4: core::option::expect_failed
             at /builddir/build/BUILD/rustc-1.65.0-src/library/core/src/option.rs:1880:5
   5: core::option::Option<T>::expect
             at /builddir/build/BUILD/rustc-1.65.0-src/library/core/src/option.rs:738:21
   6: <*mut wgpu_native::native::WGPUAdapterImpl as wgpu_native::native::UnwrapId<wgpu_core::id::Id<wgpu_core::instance::Adapter<wgpu_hal::empty::Api>>>>::unwrap_handle
             at /shared/src/wgpu-native/src/lib.rs:138:33
   7: wgpuAdapterEnumerateFeatures
             at /shared/src/wgpu-native/src/device.rs:183:30
   8: printAdapterFeatures
             at /home/user/src/wgpu-native/examples/framework.c:136:18
   9: main
             at /home/user/src/wgpu-native/examples/triangle/main.c:179:3
  10: __libc_start_main
  11: <unknown>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
fatal runtime error: failed to initiate panic, error 5
[Warn] No config found!
[Warn] EGL says it can present to the window but not natively
/bin/sh: line 1: 10211 Aborted                 (core dumped) "build/triangle"
make: *** [run-example-triangle] Error 134

NOTE: the glfw examples run fine for me.