[GHC] #13217: configure script uses different CFLAGS from the actual build

[GHC]

#13217: configure script uses different CFLAGS from the actual build
-------------------------------------+-------------------------------------
        Reporter:  dobenour          |                Owner:
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Build System      |              Version:  8.1
      Resolution:                    |             Keywords:  autoconf
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Building GHC      |  Unknown/Multiple
  failed                             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by rwbarton):

 Could you be more specific? There are various sets of flags and even
 potentially multiple C compilers that will be used at different points
 during the build of GHC.

 And in the instance in Phab:D2996, it looks like the failure occurred
 while compiling the RTS; but `-Werror` was in effect only because this was
 part of a validate build. More generally the user can specify additional
 options for building the RTS via the make variable `GhcRtsCcOpts`, and we
 can't know the value of that variable at configure time.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13217#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler