[GHC] #14965: GHC 8.4.1 bug: -O + separate compilation + three list fields + concatenation; core-lint fails

[GHC]

#14965: GHC 8.4.1 bug: -O + separate compilation + three list fields +
concatenation; core-lint fails
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        Reporter:  blynn             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.4.1
      Resolution:                    |             Keywords:  DWARF
Operating System:  Linux             |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Actually I think it may be directly related to #14779, which is fixed in
 8.4.2.   The DWARF bit may be the 'ticks' which are floating around.  The
 Lint error (in corelint.dump) relates to a top level literal string with a
 tick wrapped around it.

 It is still astonishing to me that we get different output though -- how
 on earth does that happen?   Maybe it's because that tick wrapped around
 the literal string is confusing the code generator too.

 Does this all work right in 8.4.2?

 How you even build GHC "with DWARF support" or otherwise?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14965#comment:4>
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