typedef void (*ft1)(int x, void** pp);
typedef void (*ft2)(int x, unsigned int** pp);

static void bah(int x, unsigned int** pp) { ; }

int main() {
	ft1 foo;
	foo = bah;
	return 0;
}

------
$ gcc fptest.c -o fptest
fptest.c: In function ‘main’:
fptest.c:8: warning: assignment from incompatible pointer type