GLF_CANCELING
!test_bit(GLF_CANCELING, &gl->gl_flags)) {
set_bit(GLF_CANCELING, &gl->gl_flags);
clear_bit(GLF_CANCELING, &gl->gl_flags);
if (test_bit(GLF_CANCELING, gflags))
if (!test_bit(GLF_CANCELING, &gl->gl_flags))
{(1UL << GLF_CANCELING), "C" })