[GHC] #14345: Warning when linking with C++ code

12 Oct 2017


      #14345: Warning when linking with C++ code
-------------------------------------+-------------------------------------
           Reporter:  crockeea       |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.2.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Incorrect
  Unknown/Multiple                   |  error/warning at compile-time
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 When linking with a C++ file, GHC 8.2.1.20170928 produces a warning
 because it runs gcc with 'std=gnu99', even when I pass 'std=c++11' to cc-
 options (when using stack, I see that the command is something like 'gcc
 std=gnu99 ... std=c++11', so it isn't *ignoring* my input, just appending
 it.) I believe this warning is new as of 8.2.

 The attached example demonstrates the problem:

 {{{
...
cabal configure
cabal build
 cc1plus: warning: command line option ‘-std=gnu99’ is valid for C/ObjC but
 not for C++
 cc1plus: warning: command line option ‘-std=gnu99’ is valid for C/ObjC but
 not for C++
 }}}
-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14345
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