Matthew Pickering authored May 03, 2023 and Marge Bot committed Jun 09, 2023

This fixes the behaviour of -keep-tmp-files when used in an OPTIONS_GHC
pragma for files with module level scope.

Instead of simple not deleting the files, we also need to remove them
from the TmpFs so they are not deleted later on when all the other files
are deleted.

There are additional complications because you also need to remove the
directory where these files live from the TmpFs so we don't try to
delete those later either.

I added two tests.

1. Tests simply that -keep-tmp-files works at all with a single module
   and --make mode.
2. The other tests that temporary files are deleted for other modules
   which don't enable -keep-tmp-files.

Fixes #23339