[jstimpfle]

Why do you keep sidestepping logical arguments with irrelevant quotes? Correct programs don't contain UB (even the fast ones), so UB is not what makes C fast.

Not checking for UB (aka invalid configurations) at runtime is what makes C (and any other language) fast - or more precisely, it's what allows compilers to emit efficient code.

Some languages / compilers rule out UB statically through the type system or other means, but that comes with tradeoffs that might, or might not, be worth making in your domain.

[pjmlp]

Because C guys keep spreading the false arguments that C was some kind of language sent by god to solve all performance issues, while we in the trenches when the language sprung into existence know it wasn't never the case.

Not to mention the fact that other programming languages, on the mainframe and workstation space, were already starting to collect the benefits of whole program optimizers.

[jstimpfle]

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