[GHC] #15660: source file modify race leads to inconsistent error message

[GHC]

#15660: source file modify race leads to inconsistent error message
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        Reporter:  joeyhess          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  low               |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  Poor/confusing    |  Unknown/Multiple
  error message                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by joeyhess):

 When I experienced this in the wild, the only problem was the surprise
 that it was mixing versions of the file; once past the surprise it was
 little bother to need to look up the code manually. So it would probably
 suffice for ghc to detect the race and not quote the wrong version of the
 file. I suppose it could use file stat information or a hash and so avoid
 keeping a copy.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15660#comment:5>
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