sbrk

Does sbrk not exist on FreeBSD-14 on arm64? Is this by design?

$ cat sb.c
#include <unistd.h>
#include <stdio.h>
int main(int c, char**v) {
        void *x = sbrk(102400);
        printf("%p\n", x);
}
$ cc sb.c
ld: error: undefined symbol: sbrk
>>> referenced by sb.c
>>>               /tmp/sb-e97caf.o:(main)
cc: error: linker command failed with exit code 1 (use -v to see invocation)