Editing Pointer (computer programming) (section)

=== Value of pointers ===
In C and C++, even if two pointers compare as equal that doesn't mean they are equivalent. In these languages ''and'' [[LLVM]], the rule is interpreted to mean that "just because two pointers point to the same address, does not mean they are equal in the sense that they can be used interchangeably", the difference between the pointers referred to as their ''provenance''.<ref>{{cite web |last1=Jung |first1=Ralf |title=Pointers Are Complicated II, or: We need better language specs |url=https://www.ralfj.de/blog/2020/12/14/provenance.html}}</ref> Casting to an integer type such as <code>uintptr_t</code> is implementation-defined and the comparison it provides does not provide any more insight as to whether the two pointers are interchangeable. In addition, further conversion to bytes and arithmetic will throw off optimizers trying to keep track the use of pointers, a problem still being elucidated in academic research.<ref>{{cite web |title=Pointers Are Complicated, or: What's in a Byte? |url=https://www.ralfj.de/blog/2018/07/24/pointers-and-bytes.html |last1=Jung|first1=Ralf}}</ref>