title: I've got a CPython C++ module with C++11 code, but I can't seem to build on travis-ci
body: <p>This project work fine on my local Ubuntu 12.04 and Mac OSX 10.10 (with fink python) machines.  I can't seem to figure out how to configure the .travis.yml to get the .cpp files to build with g++-4.8 (4.9 or 5.x) would be fine too.</p>
  
  <p>Project: <a href="https://github.com/schwehr/libais" rel="nofollow">https://github.com/schwehr/libais</a></p>
  
  <p>My most recent failed attempt:</p>
  
  <pre><code>language: python
  
  python:
    - "2.7"
    - "3.4"
  
  before_install:
    - sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
    - sudo apt-get update -qq
    - if [ "$CXX" = "g++" ]; then export CXX="g++-4.8" CC="gcc-4.8"; fi
  
  install:
    - sudo apt-get install -qq gcc-4.8 g++-4.8
    - python setup.py install
  
  script:
    - python setup.py test 
  </code></pre>
  
  <p>Gives:</p>
  
  <pre><code>gcc -pthread -fno-strict-aliasing -g -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -I/opt/python/2.7.9/include/python2.7 -c src/libais/ais_py.cpp -o build/temp.linux-x86_64-2.7/src/libais/ais_py.o -std=c++11
  cc1plus: warning: command line option ‘-Wstrict-prototypes’ is valid for Ada/C/ObjC but not for C++ [enabled by default]
  cc1plus: error: unrecognized command line option ‘-std=c++11’
  </code></pre>
  
  <p>The key portion of my setup.py:</p>
  
  <pre><code>EXTRA_COMPILE_ARGS = []
  if sys.platform in ('darwin', 'linux', 'linux2'):
      EXTRA_COMPILE_ARGS = ['-std=c++11']
  
  AIS_MODULE = Extension(
      '_ais',
      extra_compile_args=EXTRA_COMPILE_ARGS,
  </code></pre>