[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):

 Actually, the data at `0x41453420` is valid: it is code,
 {{{
 >>> x/8i 0x41453420
    0x41453420:  add    $0x18,%r12
    0x41453424:  cmp    0x358(%r13),%r12
    0x4145342b:  ja     0x41453450
    0x4145342d:  movq   $0x414533d0,-0x10(%r12)
    0x41453436:  mov    %rsi,(%r12)
 }}}
 This is precisely the code that I would expect given the object file. I
 don't know why my previous watchpoint didn't catch this being mapped (oh,
 perhaps gdb doesn't catch changes due to `mmap` events; that would explain
 it).

 Anyways, in this case I'm quite confused: the relocations all appear to be
 correct but we appear to be doing an indirect jump through `0x41453420`,
 clearly expecting it to be an address where in fact it is code. This
 suggests that things went awry quite a bit earlier.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14291#comment:18>
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