[torstenvl]

> From cryptic "undefined behaviors" to . . . [the] lack of a single reference implementation of the compiler/libC, and you have a language that is harsh to defend.

I think you're confused, because this is internally incoherent.

In single reference implementation languages, all behavior is undefined behavior. Undefined behavior is just behavior for which there are no requirements imposed by the international standard. It's an unbounded form of implementation-defined behavior.

Undefined behavior does not mean that the behavior is completely unpredictable. It does mean you should read your compiler's documentation (including tweaking what happens with certain common UB). For example, if you want signed integer overflow to always wrap, and you read the GCC or Clang documentation, you'll know to use -fwrapv. If overflow could cause catastrophic failure and the program should abort if it happens (e.g., Therac-25), you'll know to use -ftrapv. There's nothing wrong with writing to an arbitrary memory address, either, if you've read your documentation and that's how your environment communicates with a particular I/O port.