[GHC] #16063: ghc-8.6.3 + Mac OSX + FFI dependency causes 'impossible happened' compiler failure

[GHC]

#16063: ghc-8.6.3 + Mac OSX +  FFI dependency causes 'impossible happened' compiler
failure
-------------------------------------+-------------------------------------
        Reporter:  benselfridge      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.3
      Resolution:                    |             Keywords:
Operating System:  MacOS X           |         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 bgamari):

 Hmmm, that archive name doesn't look quite right.

 I tried to reproduce this but ran into two issues:

  * I do not have root access to a macOS box; can you modify the `install`
 rule of `softfloat-hs` to accomodate non-root users?
  * the commit 1d4010468c307c7262fc66c3d1caeb3b3d468640 of `test/riscv-
 tests` is not reachable via any branch:
 {{{
 $ git submodule update
 error: Server does not allow request for unadvertised object
 1d4010468c307c7262fc66c3d1caeb3b3d468640
 Fetched in submodule path 'test/riscv-tests', but it did not contain
 1d4010468c307c7262fc66c3d1caeb3b3d468640. Direct fetching of that commit
 failed.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16063#comment:1>
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