How recently? Both gcc 4.1.2 (2007) and clang 3.0.0 (2011) optimizes `x+1 > x` to true for a signed int `x` on -O1. And it probably goes way back, these are just the oldest compilers I found on godbolt.
The thing is it's very hard to draw the line once you go that route. Different people expect different things from undefined behavior. The best thing is to not expect anything sane. And if you are unhappy about certain undefined behaviors in the standard then it's better to push the standard to define more behavior. Certain unnecessary undefined behaviors get resolved with newer standards, although I would expect significant pushback on defining the behavior signed integer overflow.
Do you have a source for this?
As I mentioned elsewhere in the thread, you can ask gcc to trap if your code is about to dereference NULL, but the compiler can't easily detect all instances of out-of-bounds array access, due to the way arrays and pointers work in C. I believe Valgrind can help detect out-of-bounds errors at runtime, but in most languages you don't need a sledgehammer like Valgrind to find these common errors.