[GHC] #15168: GHC HEAD crashes on Windows 64 after the SRT overhaul (May 16, 2018 and newer)

[GHC]

#15168: GHC HEAD crashes on Windows 64 after the SRT overhaul (May 16, 2018 and
newer)
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        Reporter:  awson             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Windows           |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonmar):

 There's nothing Windows-specific in the GC'ing of CAFs that I'm aware of.
 There are no Windows-specific conditionals in the SRT code generation, nor
 in the garbage collector, so I'm mystified about how this is failing.

 The only wrinkle I know about is the old `COMPILING_WINDOWS_DLL` hacks
 that we had to support SRT references in another DLL:
 https://phabricator.haskell.org/diffusion/GHC/browse/master/rts/sm/Scav.c;bfc1fc2566944a455572303cbb2cbbf0c539c871$393-409

 I removed that code, but it wasn't active in any case because we aren't
 doing shared libraries on Windows, and as far as I could tell it couldn't
 have worked anyway because the code generator had no support for
 generating these references (that part probably got lost earlier).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15168#comment:7>
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