Scipy build failures with PREFIX on include / library path

[matthew-brett]

Trying to fix #58 in a general way, we put the build PREFIX into CPPFLAGS and the LDFLAGS - see https://github.com/matthew-brett/multibuild/pull/67/files . However this causes a scipy build failure - see scipy/scipy#8136 and https://travis-ci.org/scipy/scipy/jobs/299202869 .

The error was:

ld: warning: directory not found for option '-Lgfortran: warning: x86_64 conflicts with i386 (arch flags ignored)
/usr/local/Cellar/gcc/6.2.0/lib/gcc/6/gcc/x86_64-apple-darwin15.6.0/6.2.0'
Undefined symbols for architecture x86_64:
  "_PyArg_ParseTupleAndKeywords", referenced from:
      _f2py_rout__fftpack_zfft in _fftpackmodule.o
      _f2py_rout__fftpack_drfft in _fftpackmodule.o
      _f2py_rout__fftpack_zrfft in _fftpackmodule.o
      _f2py_rout__fftpack_zfftnd in _fftpackmodule.o
      _f2py_rout__fftpack_destroy_zfft_cache in _fftpackmodule.o
      _f2py_rout__fftpack_destroy_zfftnd_cache in _fftpackmodule.o
      _f2py_rout__fftpack_destroy_drfft_cache in _fftpackmodule.o
      ...
  "_PyBytes_FromString", referenced from:
      _PyInit__fftpack in _fftpackmodule.o
...

@xoviat kindly reverted the PREFIX changes in #71, #74.

This seems to be a problem with our gfortran install no longer finding the Python includes - time to investigate ...

[matthew-brett]

Hmm - the install is rather invasive for my poor laptop, involving:

brew install gcc ccache libmpc

I think this is not urgent, and I hope to have a beastly Mac Pro on my desk in a week or so, so I propose to wait until then to track this down. @xoviat @radarhere - is it OK to wait to debug this until the end of next week?

[ghost]

Sounds ok to me.

[radarhere]

Sure, that's fine - thanks for looking into it

[isuruf]

Isn't this the old numpy.distutils "feature" where LDFLAGS env variable is used when set instead of appending the values of that variable?

numpy/numpy#7427