For a new project, I have been trying to build the
threepenny-gui package, something which I have done many times in the past without any trouble. This time however, I ran into an unusual error message:
Now, a quick Google shows that this error message has been seen before — in 2010, after which it was fixed with a GHC update. I tried changing GHC versions (that output above was with GHC 8.8.4), but it didn’t work with 8.8.3 or 8.8.2 either. I also tried deleting
regex-posix¹ and reinstalling it again, but that didn’t work either. At this point, I must confess that this error has completely stumped me; does anyone else have any idea what might be causing it, and if so, how can I fix it?
¹ Specifically, I removed
C:\sr\snapshots\14724cfd\pkgdb\regex-posix-0.96.0.0-11M5Q2Uki3ACYikP2WXOuq.conf, and did
ghc-pkg unregister regex-posix.