[GHC] #15853: Unregisterised GHC panics when building test cgrun018

[GHC]

#15853: Unregisterised GHC panics when building test cgrun018
-------------------------------------+-------------------------------------
           Reporter:  iliastsi       |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  high           |         Milestone:
          Component:  Compiler       |           Version:  8.4.3
  (CodeGen)                          |
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Compile-time
  Unknown/Multiple                   |  crash or panic
          Test Case:  cgrun018       |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 An unregisterised ghc-8.4 on amd64 panics when building test cgrun018.

 {{{
 Compile failed (exit code 1) errors were:
 [1 of 1] Compiling Main             ( cgrun018.hs, cgrun018.o )
 ghc-stage2: panic! (the 'impossible' happened)
   (GHC version 8.4.4 for x86_64-unknown-linux):
         pprStatics: float
   F32
   F32
   F32
   F32
   F32
   F32
   F32
   F32
   F32
   F32
   F32
   Call stack:
       CallStack (from HasCallStack):
         callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in
 ghc:Outputable
         pprPanic, called at compiler/cmm/PprC.hs:525:5 in ghc:PprC
 }}}

 We have seen this error while building packages for Debian on 64-bit
 architectures where GHC is unregisterised (e.g., mips64el, s390x):
 [https://buildd.debian.org/status/fetch.php?pkg=haskell-
 gloss&arch=mips64el&ver=1.13.0.1-1&stamp=1540810998&raw=0 gloss on
 mips64el],
 [https://buildd.debian.org/status/fetch.php?pkg=haskell-
 juicypixels&arch=s390x&ver=3.2.9.5-3&stamp=1540808360&raw=0 juicypixels on
 s390x]

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15853>
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