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Opened by sheaf@trac-sheafDeveloper

GHCi 9.0 hangs when trying to run a program that otherwise runs fine

Summary

I'm testing out GHC-9.0.1-rc1, and encountered an issue when trying to run a program in GHCi. GHCi hangs, without any indication of what the problem might be.

Steps to reproduce

Unfortunately I don't have a simple reproducer, but all of the example applications in my shader library seem to run into the same problem. To reproduce (Linux & Windows only):

git clone https://gitlab.com/sheaf/fir
cd fir/fir-examples
cabal repl JuliaSet

ghci> main
[... hangs]

Note that running the executables directly works fine, e.g. in this case cabal run JuliaSet runs without problems.
On previous versions of GHC, the programs run in GHCi without problems.

Show/hide further info about running the reproducer.

Additional info for running the reproducer

The examples require SDL and the Vulkan SDK to be installed, visible to cabal. The library has installation instructions; in my case I installed the Vulkan SDK from the LunarG website at C:/VulkanSDK/1.2.154.1/, and have the following cabal.project.local file:

with-compiler: C:/Haskell/GHC/ghc-9.0.1-rc1/bin/ghc.exe

package vulkan
  extra-lib-dirs: C:/VulkanSDK/1.2.154.1/Lib

package vulkan-utils
  extra-lib-dirs: C:/VulkanSDK/1.2.154.1/Lib
  extra-include-dirs: C:/VulkanSDK/1.2.154.1/Include/

Environment

GHC 9.0-rc1, on Windows 10 x64. For the moment I am assuming this is Windows specific (until someone can reproduce on Linux).

Please let me know how to attempt debugging this; currently I don't know what's happening beyond GHCi hanging (which I realise is not very helpful).