I have tested "pure OpenBSD" way to reproduce problem and I can confirm that in this configuration bug is fixed.
sysctl kern.version
kern.version=OpenBSD 5.9-current (GENERIC.MP) #2002: Sun May 1 06:35:58 MDT
2016
dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
