buildworld failure with -Os

CFLAGS=-Os -pipe (-Os is basically -O2)

.9\" -DDAEMON_UID=1 -DDAEMON_GID=1  -DDEFAULT_BATCH_QUEUE=\'E\'
-DDEFAULT_AT_QU
EUE=\'c\' -DPERM_PATH=\"/var/at/\" -I/usr/src/libexec/atrun/../../usr.bin/at
-I/
usr/src/libexec/atrun   -o atrun atrun.o gloadavg.o
/usr/obj/usr/src/i386/usr/lib/libc.so: undefined reference to
`pthread_mutex_des
troy_int'
/usr/obj/usr/src/i386/usr/lib/libc.so: undefined reference to
`pthread_cond_dest
roy_exp'
/usr/obj/usr/src/i386/usr/lib/libc.so: undefined reference to
`pthread_mutex_try
lock_exp'
/usr/obj/usr/src/i386/usr/lib/libc.so: undefined reference to
`pthread_key_creat
e_int'


and zillion of others... I also had to disable CXXFLAGS which was set to
CXXFLAGS+= -fmemoize-lookups -fsave-memoized

roman