gcc-3.4.4-20050211: maybe a danger behaviour

Consider the following example:

enum w {
// c=-1,

    a,
    b
};
whattodo (
    char option
) {
    static
    struct todo {
        enum w what;
        char option;
    } todos[]= {
        {a,'a'},
        {b,'b'},
        {-1}
    };
    struct todo *p= todos;
    do if (
        (option && !option)
    ) break;
    while ((++p)->what >= 0);
    return p->what;
}

Compiling with -O[>0] and -Wall for x86 we have that code for whattodo:

whattodo:
.L2:

	jmp	.L2

a) Formally, the code is correct. As p->what can never be < 0 according to its type.

b) GCC _silently_ allows the {-1} initialization for that type, even with -Wall.

Uncommenting the c= -1 member of enum, or explicit casting p->what to int solves the problem, of course. But maybe some warning would be appropriate in such a situation? It takes some time for me to recognize what leads me to that cool .L2: jmp .L2 from seemengly harmless C code... Or maybe I don't know some healthy compiler option?