I'm trying to build CPython using Clang, with very specific requirements:

* [Python 2.7.14](https://www.python.org/ftp/python/2.7.14/Python-2.7.14.tgz)
* CentOS 6.9 (but settling for Ubuntu 16.04), x64
* [LLVM 5.0.0](http://releases.llvm.org/download.html#5.0.0)

I tried setting env variable `CC` to my clang executable location (i.e. `/opt/llvm/5/bin/clang`, but the `./configure` command fails with the following:

`configure: error: C compiler cannot create executables`

What flags should I set to make this build work?