[BUG] broken C code generated: variable undeclared

[matwey]

Describe the bug

Hello,

I am running Cython 3.0.11 with gcc 7.5.0. When I compile attached minimal example I see the following issue with C compiler:

      src/chunksize/my.c: In function ‘__pyx_f_2my__foo’:
      src/chunksize/my.c:4743:33: error: ‘__pyx_v_chunksize’ undeclared (first use in this function); did you mean ‘__pyx_k_chunksize’?
                           __pyx_t_3 = __pyx_v_chunksize;
                                       ^~~~~~~~~~~~~~~~~
                                       __pyx_k_chunksize
      src/chunksize/my.c:4743:33: note: each undeclared identifier is reported only once for each function it appears in

Code to reproduce the behaviour:

import numpy as np
from cython.parallel cimport prange, parallel

cimport numpy as np
cimport cython

def foo(int chunksize=0):
        return _foo(chunksize)

@cython.boundscheck(False)
@cython.wraparound(False)
cdef void _foo(int chunksize=0):
        cdef Py_ssize_t x_index

        with nogil, parallel():
                for x_index in prange(1024, schedule='static', chunksize=chunksize):
                        pass

Expected behaviour

The code compiled successfully.

OS

Linux

Python version

3.11.9

Cython version

3.0.11

Additional context

No response

[da-woods]

If you add x = chunksize or even <void>chunksize before the with nogil, parallel() block then it works.

I think it only unpacks the optional arguments that it believes are used, and it somehow misses the use as an argument to prange.

Definitely a bug though, thanks