--- libs/variant/perf/Jamfile.v2.orig	2019-04-09 21:36:50.000000000 +0200
+++ libs/variant/perf/Jamfile.v2	2020-06-30 15:30:37.415256000 +0200
@@ -18,6 +18,7 @@
 #      <library>/boost/system//boost_system
       <link>static
       <target-os>freebsd:<linkflags>"-lrt"
+      <target-os>bsdsunix:<linkflags>"-lrt"
       <target-os>linux:<linkflags>"-lrt"
       <toolset>gcc:<cxxflags>-fvisibility=hidden
       <toolset>intel-linux:<cxxflags>-fvisibility=hidden