Automating GHC build for Windows

Páli Gábor János pali.gabor at
Tue Nov 4 22:16:37 UTC 2014

2014-11-03 1:24 GMT+01:00 Gintautas Miliauskas <gintautas.miliauskas at>:
> Without knowing much about the surrounding code, I would try two things
> here.
> 2. Since the error is completely deterministic, you could try "freezing"
> evaluation right before the crash ([..] just
> adding a time delay / console read on the code), and then using a utility
> app to check which process is keeping the file open, whether it's the same
> process or something else.

I tried this approach and it seems I do not even need to check the
environment further: when ghc-cabal.exe stops in writeFileAtomic
(waiting for a keypress) and displays the parameters it was called
with, it says that the same dist-boot\setup-configXXXX.tmp file is
about to renamed (to dist-boot\setup-config) twice after each other
(perhaps from different threads?)!  Note that I do not experience the
same when the writeFileAtomic function is called for other files.

Well, I guess this can easily cause the problems I have seen so far...
I can also imagine that this bug is present on other systems as well,
but does not cause any harm (for some reason) so it is basically

However, first it would be nice if somebody else could confirm that it
is indeed the case.

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