[GHC] #14097: -ddump-json doesn't interact as expected with -ddump-to-file

[GHC]

#14097: -ddump-json doesn't interact as expected with -ddump-to-file
-------------------------------------+-------------------------------------
        Reporter:  mpickering        |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  JSON
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by mpickering):

 The problem is that `dumpPrefix` is set in DriverPipeline but then this
 modified version of `DynFlags` is not propagated outwards and so it is not
 set at the time `jsonLogFinaliser` calls `dumpSDoc`. This means that
 `chooseDumpFile` fails as `dumpPrefix` is not set and the output is
 instead forwarded onto stdout.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14097#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler