In the boost::any alternative implementation being developed by Pablo Aguilar and myself (latest version at http://www.codeproject.com/cpp/dynamic_typing.asp ) we have run into a problem of alignment with no obvious answer. We are trying to do the following: struct any { void* table; void* object; ... template<typename T> any(const T& x) { table = any_detail::get_table<T>::get(); if (sizeof(T) <= sizeof(void*)) { if (new(&object) T(x) != &object) { throw runtime_error("can not align the data type ... pigs must be flying"); } } } else { object = new T(x); } } The question I have is whether in practice though are there are any compilers which have stricter alignment requirements on small types (<= sizeof(void*)) than a void pointer. In other words, is it possible with any known compiler to actually throw the runtime error ? Unfortunately there is another problem, I am not an expert in interepreting the standard, but AFAICT placement new is guaranteed to return a pointer to properly aligned memory (3.7.3.1 / 2) which I leverage to check that alignment occured. Apparently not every STL implementation does in fact do that (I believe at least dinkumware is guilty of that). Thanks in advance for your help! Christopher Diggins http://www.cdiggins.com