[GHC] #14291: Tests tend to fail in the ext-interp way when split sections is enabled

[GHC]

#14291: Tests tend to fail in the ext-interp way when split sections is enabled
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:  13716
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 So, to recap, it appears that my theory from comment:13 is wrong: the
 relocation in `s1MQ_info` (see comment:9) appears to be consistent with
 what `objdump` says the target should be and with where the RTS says it
 mapped the target section.

 However, it occurred to me that maybe I'm focusing on the wrong
 relocation: the crash occurs when we attempt a `jmpq *($rbx)` where `$rbx`
 was computed (through quite a long chain) from the bits mentioned in
 comment:9. Perhaps instead it is a relocation at the address `*($rbx)`
 (which resolves to `base_DataziData_zdfDataAnyzuzdcgfoldl_closure`) that
 is the at fault.

 `objdump` says the following about this symbol,
 {{{
 00000000000386f0 <base_DataziData_zdfDataAnyzuzdcgfoldl_closure>:
         ...
                         386f0: R_X86_64_64
 base_DataziData_zdfDataAnyzuzdcgfoldl_info
 }}}
 So indeed there is a relocation there.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14291#comment:17>
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