[GHC] #15948: Hadrian cannot build on Windows

[GHC]

#15948: Hadrian cannot build on Windows
-------------------------------------+-------------------------------------
           Reporter:  bgamari        |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  highest        |         Milestone:  8.8.1
          Component:  Build System   |           Version:  8.7
  (Hadrian)                          |
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 The Hadrian build on Windows currently fails with
 {{{
 'C:/msys64/home/ben/ghc/builds/0/project-0/_build/stage0/bin/ghc.exe'
 exited
 ghc.exe: could not detect mingw toolchain
 }}}
 when trying to build the RTS.

 I strongly suspect that the problem is that the stage1 toolchain built by
 Hadrian lives in `_build/stage0/bin/ghc` whereas the mingw tarballs were
 extracted to `inplace/mingw`. It's quite unclear to me how this ever
 worked.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15948>
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