Trouble groking cython memoryviews ... how do I implement here? - cython

Question

Two functions: one which creates a 32-million integer array and another which uses it for a lookup millions of times.
from cpython cimport array as c_array
from array import array
def get_lut(file_location):
cdef c_array.array lut
with open(file_location, "rb") as f:
lut = array("I", f.read())
return lut
def use_lut(int[:] lut):
// Do a whole bunch of lookups.
Compiling with the following command:
c:\Users\Michael\Documents\Poker>set DISTUTILS_USE_SDK=1
c:\Users\Michael\Documents\Poker>python setup.py build_ext -i --compiler=msvc
Produces the following output:
Compiling handeval.pyx because it changed.
Cythonizing handeval.pyx
warning: View.MemoryView:288:5: Cannot profile nogil function.
warning: View.MemoryView:763:5: Cannot profile nogil function.
warning: View.MemoryView:899:5: Cannot profile nogil function.
warning: View.MemoryView:1063:5: Cannot profile nogil function.
warning: View.MemoryView:1070:5: Cannot profile nogil function.
warning: View.MemoryView:1124:5: Cannot profile nogil function.
warning: View.MemoryView:1131:5: Cannot profile nogil function.
warning: View.MemoryView:1142:5: Cannot profile nogil function.
warning: View.MemoryView:1163:5: Cannot profile nogil function.
warning: View.MemoryView:1223:5: Cannot profile nogil function.
warning: View.MemoryView:1295:5: Cannot profile nogil function.
warning: View.MemoryView:1317:5: Cannot profile nogil function.
warning: View.MemoryView:1352:5: Cannot profile nogil function.
warning: View.MemoryView:1362:5: Cannot profile nogil function.
running build_ext
building 'handeval' extension
C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\Bin\amd64\cl.exe /c /nolo
go /Ox /MD /W3 /GS- /DNDEBUG -IC:\Users\Michael\Anaconda3\include -IC:\Users\Mic
hael\Anaconda3\include /Tchandeval.c /Fobuild\temp.win-amd64-3.4\Release\handeva
l.obj
handeval.c
handeval.c(2391) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'long',
possible loss of data
handeval.c(2420) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'int',
possible loss of data
handeval.c(2449) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'int',
possible loss of data
handeval.c(2478) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'int',
possible loss of data
handeval.c(2507) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'int',
possible loss of data
handeval.c(2536) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'int',
possible loss of data
handeval.c(2565) : warning C4244: '+=' : conversion from 'Py_ssize_t' to 'int',
possible loss of data
handeval.c(12955) : error C2275: 'PyGILState_STATE' : illegal use of this type a
s an expression
C:\Users\Michael\Anaconda3\include\pystate.h(191) : see declaration of '
PyGILState_STATE'
handeval.c(12955) : error C2146: syntax error : missing ';' before identifier '_
_pyx_gilstate_save'
handeval.c(12955) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13026) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13052) : error C2275: 'PyGILState_STATE' : illegal use of this type a
s an expression
C:\Users\Michael\Anaconda3\include\pystate.h(191) : see declaration of '
PyGILState_STATE'
handeval.c(13052) : error C2146: syntax error : missing ';' before identifier '_
_pyx_gilstate_save'
handeval.c(13052) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13125) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13152) : error C2275: 'PyGILState_STATE' : illegal use of this type a
s an expression
C:\Users\Michael\Anaconda3\include\pystate.h(191) : see declaration of '
PyGILState_STATE'
handeval.c(13152) : error C2146: syntax error : missing ';' before identifier '_
_pyx_gilstate_save'
handeval.c(13152) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13242) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13909) : error C2275: 'PyGILState_STATE' : illegal use of this type a
s an expression
C:\Users\Michael\Anaconda3\include\pystate.h(191) : see declaration of '
PyGILState_STATE'
handeval.c(13909) : error C2146: syntax error : missing ';' before identifier '_
_pyx_gilstate_save'
handeval.c(13909) : error C2065: '__pyx_gilstate_save' : undeclared identifier
handeval.c(13935) : error C2065: '__pyx_gilstate_save' : undeclared identifier
error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio 10.0\\VC\\Bin\\
amd64\\cl.exe' failed with exit status 2
Whereas removing the int[:] type declaration from the use_lut signature compiles fine.
What am I doing wrong here?