Just FYI, to build ffmpeg with "USE_SYSTRACE=Yes", I had to have the following change to systrace.filter[1]; Evidently, due to their config mechanism change, invoking raise(3).
--patrick [1] Index: systrace.filter =================================================================== RCS file: /cvs/obsd/ports/infrastructure/db/systrace.filter,v retrieving revision 1.50 diff -u -p -u -p -r1.50 systrace.filter --- systrace.filter 5 Nov 2015 12:10:33 -0000 1.50 +++ systrace.filter 16 Nov 2015 23:56:09 -0000 @@ -4,6 +4,7 @@ native-__set_tcb: permit native-__tfork: permit native-__threxit: permit + native-thrkill: permit native-__thrsigdivert: permit native-__thrsleep: permit native-__thrwakeup: permit