[GHC] #14504: Nofib is broken on Windows

[GHC]

#14504: Nofib is broken on Windows
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  NoFib benchmark   |              Version:  8.2.1
  suite                              |
      Resolution:                    |             Keywords:
Operating System:  Windows           |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Phyx-):

 It's broken because `ghc --info` doesn't expand `$topdir` as one would
 expect it to.

 {{{
 > ghc --info
  [("Project name","The Glorious Glasgow Haskell Compilation System")
  ,("GCC extra via C opts"," -fwrapv")
  ,("C compiler command","$topdir/../mingw/bin/gcc.exe")
  ,("C compiler flags"," -fno-stack-protector")
  ,("C compiler link flags","")
  ,("Haskell CPP command","$topdir/../mingw/bin/gcc.exe")
  ,("Haskell CPP flags","-E -undef -traditional ")
  ,("ld command","$topdir/../mingw/bin/ld.exe")
 }}}

 It used work only by accident because of my earlier bug which emitted
 hard-coded paths in the settings file.

 Looks like the bug here is that GHC doesn't report something useful for
 `--info`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14504#comment:2>
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