Losing the magic

Posted Dec 7, 2022 19:48 UTC (Wed) by pizza (subscriber, #46)
In reply to: Losing the magic by Wol
Parent article: Losing the magic

> And it's all very well khim saying "the compiler writers have given you an opt-out". But SchrodinUB should always be opt IN.

The thing is... they are! Run GCC without any arguments and you'll get -O0, ie "no optimization".

These UB-affected optimizations are only ever attempted if the compiler is explicitly told to try.

Now what I find hilarious are folks who complain about the pitfalls of modern optimization techniques failing on their code while simultaneously complaining "but without '-O5 -fmoar_ponies' my program is too big/slow/whatever". Those folks also tend to ignore or disable warnings, so.. yeah.