tevent compiles correctly on an amd64 platform.  However during compilation on a 32 bit platform fails. Default compiler gcc version 4.2.1 20070831 patched [FreeBSD] is used.  

When samba 4.0.4, 4.0.5 or 4.0.6 are compiled on the same machine, libtevent.so is successfully linked, unfortunately confusing the issue.

[19/25] Compiling tevent_poll.c
./tevent_poll.c: In function 'poll_event_loop_poll':
./tevent_poll.c:553: warning: comparison is always false due to limited range of data type
[20/25] Compiling tevent_signal.c
[21/25] Compiling tevent_standard.c
[22/25] Compiling tevent_timed.c
[23/25] Compiling tevent_util.c
[24/25] Compiling tevent_wakeup.c
[25/25] Linking default/libtevent.so
default/tevent_poll_1.o: In function `poll_event_loop_once':
tevent_poll.c:(.text+0x882): undefined reference to `__stack_chk_fail_local'
default/tevent_signal_1.o: In function `signal_pipe_handler':
tevent_signal.c:(.text+0xbc1): undefined reference to `__stack_chk_fail_local'
default/lib/replace/replace_2.o: In function `rep_get_current_dir_name':
replace.c:(.text+0xa3): undefined reference to `__stack_chk_fail_local'
Waf: Leaving directory `/var/ports/usr/ports/devel/tevent/work/tevent-0.9.18/bin'
Build failed:  -> task failed (err #1):
        {task: cc_link tevent_1.o,tevent_debug_1.o,tevent_fd_1.o,tevent_immediate_1.o,tevent_queue_1.o,tevent_req_1.o,tevent_select_1.o,tevent_poll_1.o,tevent_signal_1.o,tevent_standard_1.o,tevent_timed_1.o,tevent_util_1.o,tevent_wakeup_1.o,replace_2.o,strptime_2.o,xattr_2.o -> libtevent.so}
*** [do-build] Error code 1

Stop in /usr/ports/devel/tevent.

Fix: 

Unknown
How-To-Repeat: cd /usr/ports/devel/tevent && make clean && make

Content of /etc/make.conf
CFLAGS+= -pipe -O2 -g0 -march=prescott -mtune=prescott
COPTFLAGS+= -march=prescott -mtune=prescott
ARCH= i386