Is there any way to give a warning when a nested function use its parent function's local variable value.

[xinglp]

Such as this code

void foo(int x)
{
    int a;
    void foo2(int i)
    {
        // I want warning for the below code.
        if (i == a){}
        x += i;
        a += i;
    }
    foo2(a);
}

Because I use nested function for better code orgnization and callback. Thanks.