[GHC] #365: GHC dies silently with faulty preprocessor

[GHC]

#365: GHC dies silently with faulty preprocessor
-------------------------------------+-------------------------------------
        Reporter:  josefs            |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.11
      Resolution:                    |                Keywords:
Operating System:  Windows           |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by Phyx-):

 More specifically, I think the issue here is with the use of
 [https://github.com/haskell/process/blob/52cad6528a01b7cca011ac1c4ef7d33b1f500532/cbits/runProcess.c
 runInteractiveProcess], which ultimately calls [https://msdn.microsoft.com
 /en-us/library/windows/desktop/ms682425(v=vs.85).aspx CreateProcess] on
 Windows. The problem is that processes created using `CreateProcess` must
 be known by the Windows loader. From the MSDN page.

      "This module can be a Windows-based application. It can be some other
 type of module (for example, MS-DOS or OS/2) if the appropriate subsystem
 is available on the local computer. "

 Since .py are not known by the system loader the call fails with `Exec
 format error`

 I think there are two solutions:
 * Specify `cmd.exe` or rather, whatever `ComSpec` is pointing to as the
 application and the preprocessor to run as the argument.
 * Alternatively use `ShellExecute` instead of `CreateProcess` to start the
 preprocessors.

 However both of them won't necessarily fix the tests that are failing,
 since that would require the .py extension to be registered to the python2
 in msys.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/365#comment:7>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler