The amount of exploits caused by such issues, is not as irrelevant as you hint at, after all if Apple developers get it wrong [1], what about all those that work in boring enterprises 9-5 and don't care one second about mundane stuff like static analyzers, warnings as errors, unit tests, code reviews.

The moment one needs to work with more than one compiler, including different versions of the same compiler, one needs to become a language lawyer to keep some sanity.

[1] I know the source of error wasn't related to these exact questions.