+ SIGTRAP.
+
+ FreeBSD kernels prior to r341800 can return stale siginfo for at
+ least some events, but those events can be identified by
+ additional flags set in pl_flags. True breakpoint and
+ single-step traps should not have other flags set in
+ pl_flags. */
+ if (pl.pl_flags != PL_FLAG_SI || pl.pl_siginfo.si_signo != SIGTRAP)