[GHC] #11231: GHC's configure script does not honour CC env var

[GHC]

#11231: GHC's configure script does not honour CC env var
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           Reporter:  hvr            |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Build System   |           Version:  7.11
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 `./configure --help` tells us that:

 {{{
 ...

 Some influential environment variables:
   CC          C compiler command
   CFLAGS      C compiler flags
   LDFLAGS     linker flags, e.g. -L<lib dir> if you have libraries in a
               nonstandard directory <lib dir>
   LIBS        libraries to pass to the linker, e.g. -l<library>
   CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir>
 if
               you have headers in a nonstandard directory <include dir>
   CPP         C preprocessor

 Use these variables to override the choices made by `configure' or to help
 it to find libraries and programs with nonstandard names/locations.

 Report bugs to <glasgow-haskell-bugs at haskell.org>.
 }}}

 However, neither

  - `CC=clang-3.8 ./configure`, nor
  - `./configure CC=clang-3.8`

 has any effect. `./configure` keeps using the `/usr/bin/gcc` in `$PATH`.

 The only invocation that has the desired effect is

  - `./configure --with-gcc=clang-3.8`

 However, this is utterly surprising and confusing to experienced
 developers who are used to Autoconf `./configure` scripts adhering to the
 conventions regarding `CC`, and contradicts the `--help` message.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11231>
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