[im3w1l]

> very rare cases in C where something is technically Undefined Behaviour, but in practice works and is recommended.

In the bad old days, such cases were very common. I think complaining about it is a part of the process that slowly resolves it.

[quelsolaar]

Lots of code has been broken because people have written UB code and then optimzers become smarter and vreak the code.

This category of we call ”usless UB” are things that wont help optimizeayions, and all major compiler have to support beacause if they dont, their users complain too much, can be relied on.

Unfortunately its very hard for the average use to know what UB can be relied on (there isnt much).