internal error: PAP object entered!

While trying to debug why my test didn't seem to be running, I got an internal error (below).

After a clean and rebuild it happened again so it's not a flake. Unfortunately I don't know what's causing it so I can't produce an MWE, but I can link to the project and commit on GitHub:

https://github.com/dspies-leapyear/persistwrap/tree/885a079923cb3eefb24db344f5e2fddee9fab425

Just run the test with:

stack test persistwrap:persistwrap-test

Progress 9/10: persistwrap-0.1.0.0test/Driver.hs
  test_widget_schemas:                 persistwrap-test: internal error: PAP object entered!
    (GHC version 8.4.4 for x86_64_apple_darwin)
    Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
persistwrap-test: SignalException 6

persistwrap-0.1.0.0: Test suite persistwrap-test failed
Completed 10 action(s).
Test suite failure for package persistwrap-0.1.0.0
    persistwrap-test:  exited with: ExitFailure (-6)
Logs printed to console

Trac metadata

Trac field	Value
Version	8.4.4
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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