[pypy-issue] Issue #2596: cvxcanon from PyPI fails to build (pypy/pypy)

[Amber Brown]

New issue 2596: cvxcanon from PyPI fails to build
https://bitbucket.org/pypy/pypy/issues/2596/cvxcanon-from-pypi-fails-to-build

Amber Brown:

OS: MacOS 10.12.5
PyPy versions: 
Python 3.5.3 (a37ecfe5f142bc971a86d17305cc5d1d70abec64, Jun 10 2017, 18:23:14)
[PyPy 5.8.0-beta0 with GCC 4.2.1 Compatible Apple LLVM 8.1.0 (clang-802.0.42)]
and
Python 2.7.13 (c925e73810367cd960a32592dd7f728f436c125c, Jun 09 2017, 01:01:49)
[PyPy 5.8.0 with GCC 4.2.1 Compatible Apple LLVM 8.1.0 (clang-802.0.42)]
(both available through Homebrew)

Steps to reproduce:

- pip install numpy
- pip install cvxcanon

Relevant failure:

```
  In file included from src/python/CVXcanon_wrap.cpp:3157:
  In file included from /tmp/pypyvenv/site-packages/numpy/core/include/numpy/arrayobject.h:4:
  In file included from /tmp/pypyvenv/site-packages/numpy/core/include/numpy/ndarrayobject.h:18:
  In file included from /tmp/pypyvenv/site-packages/numpy/core/include/numpy/ndarraytypes.h:1809:
  /tmp/pypyvenv/site-packages/numpy/core/include/numpy/npy_1_7_deprecated_api.h:15:2: warning: "Using deprecated NumPy API, disable it by "          "#defining NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION" [-W#warnings]
  #warning "Using deprecated NumPy API, disable it by " \
   ^
  src/python/CVXcanon_wrap.cpp:5146:12: error: no matching function for call to 'PyPySlice_Check'
        if( !PySlice_Check(slice) ) {
             ^~~~~~~~~~~~~
  /tmp/pypyvenv/include/pypy_decl.h:748:23: note: expanded from macro 'PySlice_Check'
  #define PySlice_Check PyPySlice_Check
                        ^~~~~~~~~~~~~~~
  /tmp/pypyvenv/include/pypy_decl.h:749:17: note: candidate function not viable: no known conversion from 'PySliceObject *' to 'PyObject *' (aka '_object *') for 1st argument
  PyAPI_FUNC(int) PySlice_Check(PyObject *arg0);
                  ^
  /tmp/pypyvenv/include/pypy_decl.h:748:23: note: expanded from macro 'PySlice_Check'
  #define PySlice_Check PyPySlice_Check
```

Full traceback attached (PyPy2), error is identical on PyPy3.