pub type PFN_cusparseSpGEMM_compute = unsafe extern "C" fn(handle: cusparseHandle_t, op_a: cusparseOperation_t, op_b: cusparseOperation_t, alpha: *const c_void, mat_a: cusparseSpMatDescr_t, mat_b: cusparseSpMatDescr_t, beta: *const c_void, mat_c: cusparseSpMatDescr_t, compute_type: cudaDataType, alg: cusparseSpGEMMAlg_t, descr: cusparseSpGEMMDescr_t, buffer_size2: *mut usize, external_buffer2: *mut c_void) -> cusparseStatus_t;