--- emx_callout_replica.ko (AB-BA proof module, original shape) ---
$ cd /root/emxkmod && make
cc  -O2 -pipe -D_KERNEL -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes
-Wmissing-prototypes -Wpointer-arith -Wcast-qual -Wold-style-definition
-Wmissing-include-dirs -Wno-pointer-sign -Winit-self -Wundef
-Wno-unused-but-set-variable -std=gnu11 -Werror -DKLD_MODULE -nostdinc [...]
-c emx_callout_replica.c
cc -Wl,--build-id=sha1 -nostdlib -Wl,--hash-style=sysv -r -Wl,-d
-o emx_callout_replica.ko emx_callout_replica.o
-rw-r--r-- 1 root wheel 9920 Sep 15 23:42 emx_callout_replica.ko
BUILD_RC=0  (-Werror clean)

--- fixed-shape rebuild (fix.diff protocol validation) ---
$ cd /root/emxkmod3 && make
[... same flags ...] -c emx_callout_replica.c
cc -Wl,--build-id=sha1 -nostdlib -Wl,--hash-style=sysv -r -Wl,-d
-o emx_callout_replica.ko emx_callout_replica.o
BUILD_RC=0