[GHC] #15608: Segfault in retainer profiling

[GHC]

#15608: Segfault in retainer profiling
-------------------------------------+-------------------------------------
        Reporter:  osa1              |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Profiling         |              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):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Description changed by osa1:

Old description:

> To reproduce, build ghc using "prof" flavor, then
>
> {{{
> $ ghc-stage2 --interactive +RTS -hr
> GHCi, version 8.7.20180905: http://www.haskell.org/ghc/  :? for help
> Loaded GHCi configuration from /home/omer/rcbackup/.ghci
> λ:1> sequence_ (replicate 100000000 (return ()))
> zsh: segmentation fault (core dumped)  ghc-stage2 --interactive +RTS -hr
> }}}

New description:

 To reproduce, build ghc using "prof" flavor, then

 {{{
 $ ghc-stage2 --interactive +RTS -hr
 GHCi, version 8.7.20180905: http://www.haskell.org/ghc/  :? for help
 Loaded GHCi configuration from /home/omer/rcbackup/.ghci
 λ:1> sequence_ (replicate 100000000 (return ()))
 zsh: segmentation fault (core dumped)  ghc-stage2 --interactive +RTS -hr
 }}}

 If I use debug runtime in stage2 compiler I can't even run the repl:

 {{{
 haskell $ ghc-stage2 --interactive +RTS -hr
 rr: Saving execution to trace directory `/home/omer/.local/share/rr/ghc-
 stage2-13'.
 GHCi, version 8.7.20180906: http://www.haskell.org/ghc/  :? for help
 zsh: segmentation fault  ghc-stage2 --interactive +RTS -hr
 }}}

--

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15608#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler