[GHC] #15728: Program with safe array operations triggers debug runtime assertion

[GHC]

#15728: Program with safe array operations triggers debug runtime assertion
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        Reporter:  osa1              |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Runtime System    |              Version:  8.6.1
      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:                    |
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Comment (by bgamari):

 It appears that the write in question comes from code emitted for
 `writeSmallArray#`:
 {{{
 Hardware watchpoint 1: *(void**) 0x4200105788

 Old value = (void *) 0xaaaaaaaaaaaaaaaa
 New value = (void *) 0x4200012f01
 0x000000000041fb51 in .Lslgf_info () at
 primitive/Data/Primitive/SmallArray.hs:191
 191       primitive_ $ writeSmallArray# sma# i# x
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15728#comment:3>
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