For the last few days, I get this (on a VAX system running -current):

cc -O2  -D_KERNEL -D_LKM -I. -I/usr/src/sys/lkm/compat/ibcs2 -I/usr/src/sys
-I/usr/src/sys/arch -Wall -Wstrict-prototypes -Wmissing-prototypes
-Wpointer-arith -Wno-uninitialized -Werror   -DCOMPAT_SVR4 -DSYSVSEM -DSYSVMSG
-DSYSVSHM -DSVR4_COMPAT_SOLARIS2 -c /usr/src/sys/compat/ibcs2/ibcs2_exec.c
cc1: warnings being treated as errors
/usr/src/sys/compat/ibcs2/ibcs2_exec.c:74: warning: initialization discards
`const' from pointer target type
*** Error code 1

Stop.

the above is from -current sup'ed as of today (January 25th, '01).