[GHC] #10288: -flate-dmd-anal triggers "Entered absent arg"

[GHC]

#10288: -flate-dmd-anal triggers "Entered absent arg"
-------------------------------------+-------------------------------------
        Reporter:  yongqli           |                   Owner:
            Type:  bug               |                  Status:  infoneeded
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Runtime crash     |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by yongqli):

 See Main.hs here: https://gist.github.com/yongqli/5dc94aeaeda2e24c6637

 You need the following packages: {{{ linear, lens, vector, vector-th-
 unbox, strict }}}

 Running with {{{ ghc Main.hs -O2 -flate-dmd-anal -fforce-recomp; ./Main
 }}} will give

 {{{ Main: Oops!  Entered absent arg w_sGY6 MVN V1 Double }}}

 It takes about 3 days's worth of work to produce a test case like this. Is
 there a better option than deleting a piece of code and then recompiling?
 I essentially have to "unwrite" my whole program. Is there a fuzzer-like
 tool that could conceivably be used?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10288#comment:3>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler