TLFLAGS_IN_TDLIST
curthread->tlflags &= ~(TLFLAGS_IN_TDLIST | TLFLAGS_DETACHED);
if (((thrd)->tlflags & TLFLAGS_IN_TDLIST) == 0) { \
(thrd)->tlflags |= TLFLAGS_IN_TDLIST; \
if (((thrd)->tlflags & TLFLAGS_IN_TDLIST) != 0) { \
(thrd)->tlflags &= ~TLFLAGS_IN_TDLIST; \