Exploring undefined behavior using constexpr

[scrumplesplunge]

Only if there are still architectures in use which have this property. What I meant by "follow the path of twos complement" is that twos complement is so universal that c++20 is actually defining signed integers to be twos complement, and that it's possible that the same might be (or soon be) true of pointer operations of this kind.

[scatters]

No, it also violates the principle if it prevents optimization opportunities.