Try as I might I can't get gcc to produce warnings for this (invocation: gcc --std=c99 -Wall -Werror -Wpedantic -Wnonnull). I can get clang to do so however.

I didn't expect to get any compiler warnings for code that passes NULL to a [static 1] parameter, so I wasn't surprised when this code compiled silently:

    #include <stdio.h>
    
    void end(int foo[static 1]) {
        printf("%d\n", *foo);
    }

    void middle(int *foo) {
        end(foo);
    }

    int main() {
        middle(NULL);
        return 0;
    }

But I was a bit disappointed that the following compiled without warning as well:

    #include <stdio.h>

    void end(int foo[static 1]) {
        printf("%d\n", *foo);
    }

    int main() {
        int *foo = NULL;
        end(foo);
        return 0;
    }