[GHC] #12661: Testsuite driver fails on Windows

[GHC]

#12661: Testsuite driver fails on Windows
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        Reporter:  bgamari       |                Owner:
            Type:  bug           |               Status:  new
        Priority:  normal        |            Milestone:
       Component:  Test Suite    |              Version:  8.0.1
      Resolution:                |             Keywords:
Operating System:  Windows       |         Architecture:  x86_64 (amd64)
 Type of failure:  None/Unknown  |            Test Case:
      Blocked By:                |             Blocking:
 Related Tickets:                |  Differential Rev(s):
       Wiki Page:                |
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Comment (by bgamari):

 Replying to [comment:5 Phyx-]:
 > Right, so I see the problem...
 >
 > You're using the msys version of python, which doesn't correctly search
 for the SO name.
 >
 Indeed it looks like that is the issue. Great catch!


 > it doesn't add the ".dll" to it. so the loader doesn't find it. What you
 want, is the mingw-w64 version of python (which is also compiled with GCC
 so MSVC runtime not needed).
 >
 > {{{
 > pacman -S mingw-w64-$(uname -m)-python3
 > }}}
 >
 > Odd, the installation of Sphinx should have installed it as well. It
 would be python3.5. The msys python is a bit broken (which is
 unsurprising, the msys versions are usually the bare minimum to get the
 msys shell itself working).
 >
 Judging from the output from that `pacman` command I suspect that the
 correct python was already installed. However...

 > correct the link from python3 -> mingw python3.5 and you should be good
 to go.

 Ahh, I suspect this is what I missed. In fact, shouldn't it also be
 necessary to symlink `python` to `python3.5` as well to ensure that no
 references to the broken python leak through? This is a rather subtle
 step, do you think you could mention this on
 [[Building/Preparation/Windows]]?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12661#comment:6>
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