Interrupting cabal-3.8.0.0.20220526 and master with ctrl+c makes it hang on windows

[jneira]

I am experiencing some weird behaviour interrupting cabal rc execution with ctrl+c in windows:
Doing a ctrl+c in the Configuring component for my package, with ghc-pkg subprocesses, hangs the program with rc1

I cant reproduce with 3.6.0.0

[Mikolaj]

Possibly introduced by #7921, even though it says "on unix systems".

could you try building cabal with process 1.6.14 or later?
building with GHC 9.2 may include that by default
I don't remember which GHC gitlab CI uses and so which which GHC the cabal binaries have been built
nor which GHC ghcup uses to build RC1 cabal
anyway, that's a long shot, process < 1.6.14 had some faults, but possibly not as grave as hanging

[jneira]

cabal in gitlab is built with ghc-8.10.7 iirc

[jneira]

I checked that pr and I did not get any hang, tests could be wrong though
#7921 (comment)

And a confirmation of the bug by another windows user would be great, i will try again with other projects myself

[Mikolaj]

Yes, dear Windows users, please reproduce.

[robx]

The "on unix systems" is just to say that the change isn't expected to necessarily fix things on Windows. It definitely does touch Windows too, and there's a decent chance of something like this slipping through...

One factor that might come into play is that GHC has two different Windows I/O managers, which behave differently with respect to types and sub-processes, see e.g. here haskell/process#235. It might be worth checking if that is involved here. (I don't really know which GHC version uses which I/O manager by default and/or whether they're switchable...)

[jneira]

in my test I used ghc-8.10.7, which did not have the new io manager
cabal release itself has been built with ghc-8.10.7
afair that new io manager is still not the default in ghc-9.2