[BUG] Tests and examples hang on MinGW (Windows)

[stemann]

Describe the bug

C++ tests and examples hang when executed on Windows using MinGW.

To Reproduce

There's a build (which includes tests and examples) of the recent main branch available for download from https://buildkite.com/julialang/yggdrasil/builds/15678#0193d95c-e190-48eb-b664-f0e384591eb5:

• Direct download: M/MLX/products/MLX.v0.21.2.x86_64-w64-mingw32-cxx11.tar.gz

Other builds (without examples and tests) are available from https://github.com/JuliaBinaryWrappers/MLX_jll.jl/releases

Dependencies:

• With https://julialang-s3.julialang.org/bin/winnt/x64/1.11/julia-1.11.2-win64.zip one gets libblastrampoline, and libopenblas etc.

tutorial.exe, distributed.exe etc. hangs, and other executables segfault:

~/Downloads/mlx/julia-1.11.2/bin$ ls -la ../../bin/
total 16724
drwx------+ 1 Administrator None        0 Dec 18 19:25 .
drwxr-xr-x+ 1 Administrator None        0 Dec 18 19:20 ..
-rwx------+ 1 Administrator None   134288 Jan  1  1970 distributed.exe
-rwx------+ 1 Administrator None 13080004 Jan  1  1970 libmlx.dll
-rwx------+ 1 Administrator None   177271 Jan  1  1970 linear_regression.exe
-rwx------+ 1 Administrator None   177768 Jan  1  1970 logistic_regression.exe
-rwx------+ 1 Administrator None   133560 Jan  1  1970 metal_capture.exe
-rwx------+ 1 Administrator None  3219625 Jan  1  1970 tests.exe
-rwx------+ 1 Administrator None   180219 Jan  1  1970 tutorial.exe

~/Downloads/mlx/julia-1.11.2/bin $ ../../bin/tests.exe
[doctest] doctest version is "2.4.11"
[doctest] run with "--help" for options
Segmentation fault

~/Downloads/mlx/julia-1.11.2/bin $ ../../bin/tutorial.exe
array([[1, 1],
       [1, 1]], dtype=float32)

# HANG

~/Downloads/mlx/julia-1.11.2/bin $ ../../bin/linear_regression.exe
Segmentation fault

~/Downloads/mlx/julia-1.11.2/bin $ ../../bin/logistic_regression.exe
Segmentation fault

~/Downloads/mlx/julia-1.11.2/bin $ ../../bin/metal_capture.exe
terminate called after throwing an instance of 'std::invalid_argument'
  what():  [new_stream] Cannot make gpu stream without gpu backend.

# HANG

~/Downloads/mlx/julia-1.11.2/bin $ ../../bin/distributed.exe
No communication backend found

# HANG

Expected behavior

Tests to pass, examples to terminate.

Desktop (please complete the following information):

• OS Version: Windows 2019
• Version git main @ 070bd43

Additional context

N/A

[awni]

If you're able to figure out where it's hanging or segfaulting.. we might be able to point you in the right direction for debugging / fixing.