HelenOS sources

__tcb_is_set       67 uspace/lib/c/generic/libc.c 	assert(!__tcb_is_set());
__tcb_is_set      753 uspace/lib/c/generic/thread/fibril.c 	assert(__tcb_is_set());
__tcb_is_set       62 uspace/lib/c/generic/thread/thread.c 	assert(!__tcb_is_set());
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