title: Can't import compiled cython function after successful compilation
body: <p>I'm testing out Cython on Windows 10 (Spyder 3.2.3) and Python 3.6.3 following the <a href="http://docs.cython.org/en/latest/src/tutorial/cython_tutorial.html" rel="nofollow noreferrer">Tutorial</a>, and I wrote this function:</p>
  
  <pre><code>from libc.stdlib cimport malloc, free
  
  cdef int** t3(int* El, int lEl):
      cdef int lElsq = lEl*lEl
      cdef int i,j
      cdef int** rr = &lt;int**&gt; malloc(2*sizeof(int*))
      for i in range(2):
          rr[i] = &lt;int*&gt; malloc(lElsq*sizeof(int))
      for i in range(lEl):
          for j in range(lEl):
              rr[0][i*lEl+j] = El[i]
              rr[1][i*lEl+j] = El[j]
      return rr
  </code></pre>
  
  <p>I put it into a <code>pyx</code> file and following the tutorial compiled it using the MS Visual Studio 14 compiler.</p>
  
  <p>Command: <code>%run setup.py build_ext --inplace</code></p>
  
  <p>Setup file:</p>
  
  <pre><code>from distutils.core import setup
  from Cython.Build import cythonize
  
  setup(
      ext_modules=cythonize("tempCython.pyx"),
  )
  </code></pre>
  
  <p>The compilation didn't throw any error and a lot of files were created:</p>
  
  <p>In the same directory as the original file:</p>
  
  <ul>
  <li>a <code>tempCython.c</code> file of the same name</li>
  <li>a <code>tempCython.cp36-win_amd64.pyd</code> file</li>
  </ul>
  
  <p>In the subdirectory <code>build\temp.win-amd64-3.6\Release</code>:</p>
  
  <ul>
  <li>a <code>tempCython.obj</code> file</li>
  <li>a <code>tempCython.cp36-win_amd64.exp</code> file</li>
  <li>a <code>tempCython.cp36-win_amd64.lib</code> file</li>
  </ul>
  
  <p>The <a href="http://docs.cython.org/en/latest/src/tutorial/cython_tutorial.html" rel="nofollow noreferrer">Cython tutorial</a> tells me I need the <code>pyd</code> file, so I removed the <code>cp36-win_amd64</code> in the filename.</p>
  
  <p>I can import it without error, but my function <code>t3</code> just never shows up, it's simply not there.</p>
  
  <p>Without any kind of error message I'm at a loss now. I have encountered errors like these before sometimes in 3rd-party packages, but I never understood what caused them. Why is my function not there?</p>
  
  <p>I'd also like to know the point of all those additional files, which ones do I actually need?</p>