[typesanitizer]

Thanks for the feedback.

The preceding paragraph had "and occasionally language features" so I thought it would be understood that I didn't mean it as an optimizer-specific thing, but on re-reading the post, I totally see how the other wording "The knobs to steer the optimizer are limited. Usually, these [...]" implies the wrong thing.

I've changed the wording to be clearer and put the D example into a different bucket.

> In some cases, languages have features which enforce performance-related properties at the semantic checking layer, hence, granting more control that integrates with semantic checks instead of relying on the optimizer: > > - D has first-class support for marking functions as “no GC”.

[WalterBright]

That's better, thanks!