[GHC] #8825: ghc can't determine gcc version on ru_RU locale

[GHC]

#8825: ghc can't determine gcc version on ru_RU locale
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        Reporter:  slyfox            |            Owner:
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.8.1-rc1
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by slyfox):

 Replying to [comment:1 juhpetersen]:
 > So `LANG=C ghc ...` or `LANG=en_US.utf8 ghc ...` do not give the
 warning?

 Yes, LANG=C "fixes" it.

 > I suspect it would be better to give an explicit example of how to
 reproduce the warning.
 > What version of binutils (for GNU ld) do you have installed?

 ghc's warning explicitely says about 'gcc' / 'clang'.
 I don't think it matters, but it's '''binutils-2.24'''.

 Once I'll manage to filter out which exactly file triggers it from 9
 parallel building threads
 I'll post a minimal example. I thought error message is obvious enough,
 but whatever:

 '''compiler/main/SysTools.lhs'''
 {{{
 -- See Note [Run-time linker info].
 getCompilerInfo' :: DynFlags -> IO CompilerInfo
 getCompilerInfo' dflags = do
   let (pgm,_) = pgm_c dflags
       -- Try to grab the info from the process output.
       parseCompilerInfo _stdo stde _exitc
         -- Regular GCC
         | any ("gcc version" `isPrefixOf`) stde =
           return GCC
         -- Regular clang
         | any ("clang version" `isPrefixOf`) stde =
           return Clang
         ...

   -- Process the executable call
   info <- catchIO (do
                 (exitc, stdo, stde) <- readProcessWithExitCode pgm ["-v"]
 ""
                 -- Split the output by lines to make certain kinds
                 -- of processing easier.
                 parseCompilerInfo (lines stdo) (lines stde) exitc
             )
             (\err -> do
                 debugTraceMsg dflags 2
                     (text "Error (figuring out compiler information):" <+>
                      text (show err))
                 errorMsg dflags $ hang (text "Warning:") 9 $
                   text "Couldn't figure out linker information!" $$
                   text "Make sure you're using GNU gcc, or clang"
                 return UnknownCC)
   return info
 }}}

 > I don't think I have seen this on Fedora anyway, so it sounds like it
 could be a Gentoo specific issue perhaps.

 Gentoo does not do translation to russian on it's own.
 What locale do you use on Fedora?
 Do you have non-english locale installed for gcc?

 That should be easy to check:
 {{{
 LANG=ru_RU.UTF-8 gcc -v 2>&1 | tail -n1
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8825#comment:2>
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