--- ./ext/POSIX/POSIX.xs.orig	2020-06-14 23:01:25.000000000 +0000
+++ ./ext/POSIX/POSIX.xs	2020-10-27 10:53:50.744531872 +0000
@@ -3110,6 +3110,10 @@ sigaction(sig, optaction, oldaction = 0)
 		/* Set up any desired flags. */
 		svp = hv_fetchs(action, "FLAGS", FALSE);
 		act.sa_flags = svp ? SvIV(*svp) : 0;
+#ifdef SA_SIGINFO
+		/* Perl_sighandler depends on the extra arguments. */
+		act.sa_flags |= SA_SIGINFO;
+#endif
 
 		/* Safe signals use "csighandler", which vectors through the
 		   PL_sighandlerp pointer when it's safe to do so.