When give a nonzero flags to getTime, c_retval will get -1 and goto cleanup. But py_retval still is NULL,so pass c_retval value to py_retval. This will make the output message more correct. error before use this patch: SystemError: error return without exception set after use the patch: libvirtError: unsupported flags (0x1) in function qemuDomainGetTime Signed-off-by: Luyao Huang <lhuang(a)redhat.com&gt; --- libvirt-override.c | 1 + 1 file changed, 1 insertion(+) diff --git a/libvirt-override.c b/libvirt-override.c index 9ba87eb..eed8d50 100644 --- a/libvirt-override.c +++ b/libvirt-override.c @@ -7758,6 +7758,7 @@ libvirt_virDomainGetTime(PyObject *self ATTRIBUTE_UNUSED, PyObject *args) { LIBVIRT_END_ALLOW_THREADS; if (c_retval < 0) + py_retval = libvirt_intWrap(c_retval); goto cleanup; if (!(pyobj_seconds = libvirt_longlongWrap(seconds)) || -- 1.8.3.1