Cleanup of Python variables wrong in nogil functions

[da-woods]

cdef void f() nogil:
    with gil:
        x = []

On current master this generates the C code:

goto __pyx_L0;
  __pyx_L1_error:;
  __Pyx_XDECREF(__pyx_t_1);
  #ifdef WITH_THREAD
  __pyx_gilstate_save = __Pyx_PyGILState_Ensure();
  #endif
  __Pyx_WriteUnraisable("xxx.f", __pyx_clineno, __pyx_lineno, __pyx_filename, 1, 0);
  #ifdef WITH_THREAD
  __Pyx_PyGILState_Release(__pyx_gilstate_save);
  #endif
  __pyx_L0:;
  __Pyx_XDECREF(__pyx_v_x);

Note that both __Pyx_XDECREFs happen outside the __Pyx_PyGILState_Ensure block.

On 0.29.x the code generated looks fine.

[scoder]

Thanks for noticing and for the short reproducer.