Does reinterpret_casting an integral to a pointer type and back yield the same value?

Question

According to http://en.cppreference.com/w/cpp/language/reinterpret_cast, it is known that reinterpret_cast a pointer to an integral of sufficient size and back

Answer 1

I get exactly this problem in library exporting pointers to objects as opaque identifiers and now attempting to recover these pointers from external calls don't work for old x86 CPU's (in the time of windows 98). So, while we can expect that behaviour, this is false in general case. In 386-CPU the address is composed by overlapped pointers so the address of any memory position is not unique, and I found that conversion back don't recover original value.