"please don't do this, you're not producing value": http://blog.metaobject.com/2014/04/cc-osmartass.html
"No sane compiler writer would ever assume it allowed the compiler to 'do anything' with your code": http://article.gmane.org/gmane.os.plan9.general/76989
"Everyone is fired": http://web.archive.org/web/20160309163927/http://robertoconc...
The really strange this is: there's probably tons of places that the compiler takes advantage of undefined behaviour, and nobody notices, and in fact is grateful of the magic speed improvement that comes for free simply from adding -O3 or whatever. And these are then used to justify the undefined behaviour that people find slightly mystifying, or that cause actual problems in practice (interestingly these always seem to be related, as in this case, to things that can be statically proven to have NULL-related undefined behaviour). But why not treat these two cases differently?
The customer is always right!