Update or arpwatch fails due to the error listed below on CURRENT (FreeBSD 11.0-CURRENT #5 r297337: Mon Mar 28 11:09:43 CEST 2016):

[...]
--- arpsnmp.o ---
--- arpwatch.o ---
./arpwatch.c:144:40: warning: unknown attribute 'volatile' ignored [-Wunknown-attributes]
__dead  void usage(void) __attribute__((volatile));
                                        ^
./arpwatch.c:211:4: error: use of undeclared identifier 'zeroflag'
                        zeroflag = 1;
                        ^
cc -O2 -pipe -O3 -march=native  -fstack-protector -fno-strict-aliasing -DPACKAGE_NAME=\"\" -DPACKAGE_TARNAME=\"\" -DPACKAGE_VERSION=\"\" -DPACKAGE_STRING=\"\" -DPACKAGE_BUGREPORT=\"\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_FCNTL_H=1 -DHAVE_MEMORY_H=1 -DTIME_WITH_SYS_TIME=1 -DHAVE_BCOPY=1 -DHAVE_STRERROR=1 -DRETSIGTYPE=void -DRETSIGVAL= -DHAVE_SIGSET=1 -Dsignal=sig--- arpsnmp.o ---
DECLWAITSTATUS=int  -DARPDIR=\"/usr/local/arpwatch\" -DPATH_SENDMAIL=\"/usr/sbin/sendmail\" -I. -c ./arpsnmp.c
--- arpwatch.o ---
./arpwatch.c:436:40: warning: format specifies type 'int' but the argument has type 'unsigned long' [-Wformat]
                syslog(LOG_ERR, "short (want %d)\n", sizeof(*eh) + sizeof(*ea));
                                             ~~      ^~~~~~~~~~~~~~~~~~~~~~~~~
                                             %lu
--- version.o ---
--- arpwatch.o ---
./arpwatch.c:588:40: warning: format specifies type 'int' but the argument has type 'unsigned long' [-Wformat]
cc -O2 -pipe -O3 -march=native  -fstack-protector -fno-strict-aliasing -DPACKAGE_NAME=\"\" -DPACKAGE_TARNAME=\"\" -DPACKAGE_VERSION=\"\" -DPACKAGE_STRING=\"\" -DPACKAGE_BUGREPORT=\"\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_FCNTL_H=1 -DHAVE_MEMORY_H=1 -DTIME_WITH_SYS_TIME=1 -DHAVE_BCOPY=1 -DHAVE_STRERROR=1 -DRETSIGTYPE=void -DRETSIGVAL= -DHAVE_SIGSET=1 -Dsignal=sig--- version.o ---
DECLWAITSTATUS=int  -DARPDIR=\"/usr/local/arpwatch\" -DPATH_SENDMAIL=\"/usr/sbin/sendmail\" -I. -c ./version.c
--- arpwatch.o ---
                syslog(LOG_ERR, "short (want %d)\n", sizeof(*fh) + sizeof(*ea));
                                             ~~      ^~~~~~~~~~~~~~~~~~~~~~~~~
                                             %lu
3 warnings and 1 error generated.
*** [arpwatch.o] Error code 1