>but it's hard to tighten the rules after the fact. Depends on what you mean by tighten the rules. If you tighten the rules for the optimizer by simply allowin

>but it's hard to tighten the rules after the fact. Depends on what you mean by tighten the rules. If you tighten the rules for the optimizer by simply allowing everything to alias, that should not introduce bugs into currently well formed programs. (Except that they might be slower.)