old_contents: from distutils.core import setup, Extension
  setup(name="fastcache", version="0.1",
        packages = ["fastcache", "fastcache.tests"],
        ext_modules= [Extension("fastcache._lrucache",
                      ["src/_lrucache.c"],
                      ),
                  ]
        
    )
  
new_contents: from distutils.core import setup, Extension
  setup(name="fastcache", version="0.1",
        packages = ["fastcache", "fastcache.tests"],
        ext_modules= [Extension("fastcache._lrucache",
                      ["src/_lrucache.c"],
                      extra_compile_args=['-std=c99']),
                  ]
        
    )
  
subject: Fix travis build error by specifying compiler arg -std=c99