make kernel build error on recent -current

[Alexey Dokuchaev]

hi there,

i'm seeing this while trying to make my kernel:

cc -c -O2 -pipe -mtune=pentium4 -march=pentium4 -fno-strict-aliasing -march=pentium4 -std=c99 -g -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes  -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  -Wundef -Wno-pointer-sign -fformat-extensions -nostdinc  -I. -I/usr/src/sys -I/usr/src/sys/contrib/altq -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common -finline-limit=8000 --param inline-unit-growth=100 --param large-function-growth=1000 -fno-builtin -mno-align-long-strings -mpreferred-stack-boundary=2  -mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 -ffreestanding -Werror  /usr/src/sys/kern/kern_intr.c
cc1: warnings being treated as errors
/usr/src/sys/kern/kern_intr.c: In function 'intr_priority':
/usr/src/sys/kern/kern_intr.c:117: warning: 'pri' may be used uninitialized in this function
*** Error code 1

it seems that `kern.pre.mk' enables -Werror despite my NO_WERROR setting.

./danfe