[GHC] #14677: Code generator does not correctly tag a pointer

[GHC]

#14677: Code generator does not correctly tag a pointer
-------------------------------------+-------------------------------------
        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  CodeGen
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:  15155             |             Blocking:  14626
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by heisenbug):

 I am going to dump here the differences between 8.6.3-created libs and
 HEAD's libs, w.r.t. exported nullary symbols:
 {{{
 $ nm
 /home/pkoeckri/.stack/programs/x86_64-linux/ghc-8.6.3/lib/ghc-8.6.3/base-4.12.0.0/libHSbase-4.12.0.0.a
 | grep evtRead
                  U base_GHCziEventziInternal_evtRead_closure
                  U base_GHCziEventziInternal_evtRead_closure
 0000000000000000 D base_GHCziEventziInternal_evtRead_closure
                  U base_GHCziEventziInternal_evtRead_closure
                  U base_GHCziEventziInternal_evtRead_closure
                  U base_GHCziEventziInternal_evtRead_closure
 }}}
 (`lib/ghc-8.4.4/base-4.11.1.0/libHSbase-4.11.1.0.a` is identical to
 above.)
 {{{
 $ nm _build/stage1/lib/x86_64-linux-
 ghc-8.7.20190106/base-4.12.0.0/libHSbase-4.12.0.0.a  | grep evtRe
                  U base_GHCziEventziInternal_evtRead1_closure
                  U base_GHCziEventziInternal_evtRead1_closure
 0000000000000290 D base_GHCziEventziInternal_evtRead1_closure
 00000000000002a0 D base_GHCziEventziInternal_evtRead_closure
                  U base_GHCziEventziInternal_evtRead1_closure
                  U base_GHCziEventziInternal_evtRead1_closure
                  U base_GHCziEventziInternal_evtRead1_closure
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14677#comment:34>
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