newbie python - cmake build problem I can't seem to fix...

[Ryan Schmidt]

> On Sep 9, 2016, at 3:06 PM, Ken Cunningham wrote:
> 
>> 
>> It's not *bad*, just not ideal. If the build system doesn't respect PYTHON_EXECUTABLE, then upstream should fix that.
> 
> True.
> 
> As it turns out, I learned how to re-write the python to be compatible with 3.x, and fixed the port that way. So that's probably the best outcome, and I'll submit that upstream for them to fix someday.

That's good. But it still suggests that the port is building with whatever "python" is, which as you've seen is different on different systems. Does the code work with the very old version of python included on macOS Tiger? Will it work with the version of python included with whatever version of macOS comes after Sierra? You might not know. It might be better to pick a known good version of python, add that as a dependency, and make the port use that. This is not just a good idea but even required if the port were to do something like install a python module (because that python module would be for that one version of python), or needs python not just to build but to run (because it would run that version of python).


> Although I'd still like to know how to adjust the $PATH, if you feel so inclined one day -- promise to use my powers for good and not for evil ...

I found a simple example of how to do this in the gupnp-igd port, which has this block:


variant python27 description {Enable Python 2.7 bindings} {
    configure.args-replace      --disable-python --enable-python
    depends_lib-append          port:py27-gobject
    configure.python            ${prefix}/bin/python2.7
    set python_prefix           ${frameworks_dir}/Python.framework/Versions/2.7
    set python_pkg_config_path  ${python_prefix}/lib/pkgconfig
    configure.pkg_config_path   ${python_pkg_config_path}
    build.env-append            PATH=${python_prefix}/bin:$env(PATH)
}