[GHC] #12060: GHC panic depending on what a Haskell module is named

[GHC]

#12060: GHC panic depending on what a Haskell module is named
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           Reporter:  Darwin226       |             Owner:
               Type:  bug             |            Status:  new
           Priority:  normal          |         Milestone:
          Component:  GHCi            |           Version:  7.10.3
           Keywords:                  |  Operating System:  Windows
       Architecture:  x86_64 (amd64)  |   Type of failure:  Runtime crash
          Test Case:                  |        Blocked By:
           Blocking:                  |   Related Tickets:
Differential Rev(s):                  |         Wiki Page:
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 I'm trying to make bindings for the imgui C++ library and have encountered
 an apparent bug. I'm unable to produce a minimal example so I've packed up
 the whole project in a zip file. It only works on Windows for now but I
 assume this problem is platform dependant anyways.

 There's a module `UI.Imgui` that imports two things. A `FunPtr` wrapping
 function and an actual function defined in a .cpp file. Another module
 Main imports this module.

 If the project is run in a repl (in my case I'm doing `stack repl`) and
 then the `test` function is evaluated it results in a GHC panic

 {{{#!hs
 ghc.exe: panic! (the 'impossible' happened)
   (GHC version 7.10.3 for x86_64-unknown-mingw32):
         loadObj
 "C:\\Users\\Luka\\AppData\\Local\\Temp\\ghc5900_0\\ghc_5.o": failed

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 }}}

 Now here's the fun part. If you rename the module, file and it's import to
 something like Imgui2 it works. If you rename it to UI2.Imgui (with
 appropriate folder renaming) it also works!

 I'm sure a huge portion of the code is irrelevant. I couldn't reproduce
 this with simple .cpp files.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12060>
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