Can you enable -Werror=format in Clang, but still allow non-literal format strings? (without using -Wno-format-security)

Question

I just added -Werror=format to our makefiles, and I started getting some errors where we were passing non-literal format strings to printf-like functions. (Yeah, not the best idea, but it was mostly in tests, and other places where it's not actually a problem, this would be a breaking change)

So I also added -Wno-format-nonliteral, but it doesn't seem to do anything: https://godbolt.org/z/1x6YvY4d5

Actually, it seems that this option is kinda broken in clang? No warnings/errors from the following when compiling w/ -Wno-format-security -Wformat-nonliteral:

#include <cstring>
#include <cstdio>

using namespace std;

void foo() {
    char buff[10];
    printf(fgets(buff, sizeof(buff), stdin));
}

https://godbolt.org/z/a5Gnz537W