[GHC] #7225: "ghc -C" failed

[GHC]

#7225: "ghc -C" failed
-------------------------+--------------------------------------------------
    Reporter:  guest     |       Owner:  igloo             
        Type:  bug       |      Status:  new               
    Priority:  high      |   Milestone:  7.8.1             
   Component:  Compiler  |     Version:  7.4.1             
    Keywords:            |          Os:  Windows           
Architecture:  x86       |     Failure:  Compile-time crash
  Difficulty:  Unknown   |    Testcase:                    
   Blockedby:            |    Blocking:                    
     Related:            |  
-------------------------+--------------------------------------------------

Comment(by goldfire):

 This panic is also triggered by building GHC with the following in
 build.mk:

 {{{
 GhcLibWays = v p dyn p_dyn
 }}}

 Here is the error:
 {{{
   ...
   rts_dist_HC rts/dist/build/posix/Signals.
   rts_dist_HC rts/dist/build/posix/TTY.
   rts_dist_HC rts/dist/build/Apply.hc

 addFlag by -C on the commandline: Warning:
     The -fvia-C flag does nothing; it will be removed in a future GHC
 release
 ghc-stage1: panic! (the 'impossible' happened)
   (GHC version 7.7.20121002 for x86_64-apple-darwin):
         pipeLoop: at phase As but I wanted to stop at phase HCc
 }}}

 If it matters, I'm compiling on Mac OS 10.7.5 and using GHC 7.6.1.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7225#comment:2>
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