[GHC] #10046: Linker script patch in rts/Linker.c doesn't work for (non-C or non-en..) locales

[GHC]

#10046: Linker script patch in rts/Linker.c doesn't work for (non-C or non-en..)
locales
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        Reporter:  hgolden           |                   Owner:  simonmar
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Runtime System    |                 Version:  7.8.4
      Resolution:                    |                Keywords:  linker
Operating System:  Unknown/Multiple  |  script
 Type of failure:  Incorrect result  |            Architecture:
  at runtime                         |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:  2615, 9237        |                Blocking:
                                     |  Differential Revisions:
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Comment (by rwbarton):

 > The only concern I have is in the case of multithreaded code that
 _might_ be affected if it is running while the locale is changed. I don't
 know enough to know if this is a real issue or not, nor do I know how to
 deal with it if necessary.

 Yes, this is an issue with `setlocale`. POSIX has `uselocale` and related
 functions which allow setting the locale on a per-thread basis, though.

 `dlopen` can execute code from the shared library it loads (constructor
 functions), so as you say we should only modify the locale around the call
 to `dlerror`, which should be safe. Really the most correct thing to do
 would be to return both the localized error message and the
 `LC_MESSAGES=C` error message from `internal_dlopen`, and use the latter
 message to detect linker scripts, and present the former message to the
 user if we ultimately can't load the shared library.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10046#comment:1>
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