> Unless you need zero byte (and other) pointers to be consistently unique. Yes, this was the problem. People had some different ideas for contracts that `mall

> Unless you need zero byte (and other) pointers to be consistently unique. Yes, this was the problem. People had some different ideas for contracts that `malloc` etc. should guarantee---the most lax requirement would be a "usable" pointer on success, which does almost perfectly constrain non-zero cases but leaves lots of freedom for zero cases. At the opposite side there is a "unique non-NULL" pointer requirement, as you've said, which essentially makes `malloc(0)` almost same to `malloc(1)`. Rust also has this issue because its reference, a pointer after compilation, is expected to be non-null even for zero-sized types. Rust's rule is somewhat in between: any pointer should be non-null, but it doesn't have to be unique for zero-sized types. The canonical non-null pointer for such types (as returned by `NonNull::dangling`) is the smallest non-zero pointer that satisfies the alignment.