> Historically, Visual C++ did not take advantage of the
> fact that the C and C++ standards consider the result
> of overflowing signed operations undefined. Other
> compilers are very aggressive in this regard, which
> motivated the decision to implement some patterns which
> take advantage of undefined integer overflow behavior.
> We implemented the ones we thought were safe and didn’t
> impose any unnecessary security risks in generated code.
> A new undocumented compiler flag has been added to
> disable these optimizations, in case an application
> that is not standard-conformant fails:
> -d2SSAOptimizerUndefinedIntOverflow-. Due to security
> concerns, we have seen cases where these patterns
> should not be optimized, even though following the C
> and C++ standards allows us to [...]
It sounds like they're not doing anything that GCC/Clang aren't already, but if you've only ever compiled with MSVC then be careful not to overlook this.
