No bounds checking for dynamic arrays at compile time?

[Walter Bright]

On 12/13/2012 1:38 AM, bearophile wrote:
> To spot at compile-time situations like:
>
>
> void main() {
>      int[5] x;
>      x[$] = 1;
>      enum size_t n = 2;
>      x[$ + n] = 2;
> }

The compiler does that already.


> void main() {
>      int[] x = new int[5];
>      x[$] = 1; // easy
>      x[x.length] = 1; // idem
>      enum size_t n = 2;
>      x[$ + n] = 2; // not too much hard if n is unsigned
>      x[x.length + n] = 2; // idem
> }

I just don't see the point in adding flow analysis for that, and it'll ding you 
at runtime anyway. There are a lot more interesting things that flow analysis 
can do.