# race5663.ko build (guest /root/poc5663, kernel 6.5-DEVELOPMENT X86_64_GENERIC)
$ { echo KMOD=race5663; echo SRCS=race5663.c; echo SYSDIR=/usr/src/sys; echo '.include "/usr/src/sys/conf/kmod.mk"'; } > Makefile && make
cc  -O2 -pipe -D_KERNEL -Wall [..] -Werror -DKLD_MODULE -nostdinc [..] -c race5663.c
cc -Wl,--build-id=sha1 -nostdlib -Wl,--hash-style=sysv -r -Wl,-d -o race5663.ko race5663.o
(no warnings, no errors; -Werror clean) => race5663.ko 9512 bytes (v2)