My understanding of the line that is removed is, that the logic is
wrong. According to the setup.py file[0] it says that:
> To exclude certain options in the cmake config use --no:
> for example:
> --no USE_AVX_INSTRUCTIONS: will set -DUSE_AVX_INSTRUCTIONS=no
This means, that a true value of `avxSupport` will deactivate it in the
setup, which is not what we want.
[0]: https://github.com/davisking/dlib/blob/v19.21/setup.py#L22
7db40fa5d5