MNT: suppress compiler warning from cupyx.cusolver

[leofang]

No description provided.

[kmaehashi]

/test mini

LGTM! Confirmed the following warning (in main) disappeared:

https://github.com/cupy/cupy/actions/runs/5529072408/jobs/10086636516#step:6:414

    gcc -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -fPIC -D_FORCE_INLINES=1 -DCUPY_NO_CUDA=1 -I/home/runner/work/cupy/cupy/cupy/_core/include/cupy/cub -I/home/runner/work/cupy/cupy/cupy/_core/include -I/opt/hostedtoolcache/Python/3.9.17/x64/include/python3.9 -c cupy_backends/cuda/libs/cudnn.cpp -o build/temp.linux-x86_64-3.9/cupy_backends/cuda/libs/cudnn.o
    cupyx/cusolver.cpp: In function ‘PyObject* __pyx_pw_5cupyx_8cusolver_21_geqrf_orgqr_batched(PyObject*, PyObject*, PyObject*)’:
    cupyx/cusolver.cpp:20661:39: warning: ‘__pyx_v_orgqr_bufferSize’ may be used uninitialized in this function [-Wmaybe-uninitialized]
    20661 |   __pyx_t_7 = __pyx_v_orgqr_bufferSize(__pyx_v_handle, __pyx_v_m, __pyx_v_mc, __pyx_v_mn, __pyx_v_x_ptr, __pyx_v_m, __pyx_v_tau_ptr, 0); if (unlikely(__pyx_t_7 == ((int)-1) && PyErr_Occurred())) __PYX_ERR(0, 965, __pyx_L1_error)
          |               ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    cupyx/cusolver.cpp:19182:9: note: ‘__pyx_v_orgqr_bufferSize’ was declared here
    19182 |   int (*__pyx_v_orgqr_bufferSize)(intptr_t, int, int, int, size_t, int, size_t, int __pyx_skip_dispatch);
          |         ^~~~~~~~~~~~~~~~~~~~~~~~
    cupyx/cusolver.cpp:20720:39: warning: ‘__pyx_v_orgqr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
    20720 |         __pyx_v_status = __pyx_v_orgqr(__pyx_v_handle, __pyx_v_m, __pyx_v_mc, __pyx_v_mn, __pyx_v_x_ptr, __pyx_v_m, __pyx_v_tau_ptr, __pyx_v_w_ptr, __pyx_v_buffersize, __pyx_v_info_ptr, __pyx_v_batch_size, __pyx_v_orig_n);
          |                          ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    cupyx/cusolver.cpp:19181:38: note: ‘__pyx_v_orgqr’ was declared here
    19181 |   __pyx_t_5cupyx_8cusolver_orgqr_ptr __pyx_v_orgqr;
          |                                      ^~~~~~~~~~~~~

[kmaehashi]

https://ci.preferred.jp/cupy.win.cuda120/137846/

NameError: name 'sorgqr_bufferSize' is not defined

Hmm, can't assign cimported function to object? 🤔

[leofang]

NameError: name 'sorgqr_bufferSize' is not defined

Hmm, can't assign cimported function to object? 🤔

Sorry, I did it in a rush and didn't check carefully, it's fixed now in commit 7337ee0.

It seems Cython has the ability to infer if a pure function pointer is being assigned, without the programmer to explicitly spelling out the type. So, the previous way cdef object sorgqr_bufferSize = None was actually wrong. By providing an else branch, Cython is smart enough to 1. generate the functor signature and 2. suppress the warning on uninitialized values.

[leofang]

/test mini

[kmaehashi]

Test failure unrelated.