An obsolete weakness occurs when someone uses deprecated or obsolete functions when building a system. As a programming language evolves, some functions occasionally become obsolete.
These functions are considered obsolete on most systems, and very non-portable.
The highlighted line of code below is the trigger point of this particular Fedora 23 obsolete weakness.
/* rt_sigprocmask may fail if: 1. sigsetsize != sizeof (sigset_t) (EINVAL) 2. a failure in copy from/to user space (EFAULT) 3. an invalid 'how' operation (EINVAL) The first case is already handle in glibc syscall call by using the arch defined _NSIG. Second case is handled by using a stack allocated mask. The last one should be handled by the block/unblock functions. */ sigset_t set; __libc_signal_block_app (&set); INTERNAL_SYSCALL_DECL (err); pid_t pid = INTERNAL_SYSCALL (getpid, err, 0); pid_t tid = INTERNAL_SYSCALL (gettid, err, 0); int ret = INLINE_SYSCALL (tgkill, 3, pid, tid, sig); __libc_signal_restore_set (&set); return ret; } libc_hidden_def (raise) weak_alias (raise, gsignal)