I think the biggest problem with undefined behavior in C is that it is taken to justify violation of C's customary semantics[1] on platforms where it isn't nece

I think the biggest problem with undefined behavior in C is that it is taken to justify violation of C's customary semantics[1] on platforms where it isn't necessary. Many types of undefined behavior in the C standard are essentially dispensations for Lisp machines or one's complement CPUs. It's very surprising to see them invoked by the optimizer on more conventional platforms. It might not satisfy djb, but a standard for these behaviors alone would be great progress.[2] [1] http://arcanesentiment.blogspot.com/2014/12/customary-semantics.html http://arcanesentiment.blogspot.com/2014/12/customary-semant... [2] Posix doesn't really address this, sadly. The committee seems to have avoided standardizing byte size until an unforeseen interaction with a later C standard pushed it into a corner.