[GHC] #15548: Make TABLES_NEXT_TO_CODE a dynflag

[GHC]

#15548: Make TABLES_NEXT_TO_CODE a dynflag
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        Reporter:  nomeata           |                Owner:  (none)
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D5082
       Wiki Page:                    |
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Comment (by nomeata):

 There is one curious spot left, in `SysTools`
 {{{
            tntc_gcc_args
             | mkTablesNextToCode targetUnregisterised
                = ["-DTABLES_NEXT_TO_CODE"]
             | otherwise = []
            cpp_args= map Option (words cpp_args_str)
            gcc_args = map Option (words gcc_args_str
                                ++ unreg_gcc_args
                                ++ tntc_gcc_args)
 }}}
 This sets the default C arguments based on the initial settings (not the
 dynflags). I am wondering if anything actually relies on GHC setting the
 flag here, especially since `/usr/lib/ghc/include/ghcautoconf.h`, included
 by various header files, _also_ sets `TABLES_NEXT_TO_CODE`.

 I guess I should just try it out.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15548#comment:3>
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