restrict in practice

[Walter Bright]

bearophile wrote:
> A downside of the restrict of C is that the compiler is not able to
> spot if the annotation is used in the wrong place.

That's a near fatal problem with it, because:

1. restrict is difficult to understand

2. it is prone to being used erroneously due to misunderstanding

3. it is not checkable by the compiler

4. even if used correctly, it can be broken by seemingly minor changes 
done later