[GHC] #14905: GHCi segfaults with +RTS -Di after hitting a breakpoint

[GHC]

#14905: GHCi segfaults with +RTS -Di after hitting a breakpoint
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        Reporter:  osa1              |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4490
       Wiki Page:                    |
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Comment (by Ömer Sinan Ağacan <omeragacan@…>):

 In [changeset:"8e3410134bd7419db638988d74fcc600b03e2a1a/ghc"
 8e341013/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="8e3410134bd7419db638988d74fcc600b03e2a1a"
 Fix a debug print in disassembler (#14905)

 When interpreter is not profiled (see `interpreterProfiled` in
 `DynFlags`) bytecode generator generates a NULL pointer as the cost
 centre of a `BRK_FUN` instruction:

     let cc | interpreterProfiled dflags = cc_arr ! tick_no
            | otherwise = toRemotePtr nullPtr
     let breakInstr = BRK_FUN (fromIntegral tick_no) (getUnique this_mod)
 cc
     return $ breakInstr `consOL` code

 We now take this into account when disassembling `BRK_FUN`.

 Reviewers: bgamari, simonmar, erikd

 Subscribers: rwbarton, thomie, carter

 Differential Revision: https://phabricator.haskell.org/D4490
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14905#comment:2>
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