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    <p>After a decent amount of research...</p> <p>This is actually done in most industrial intrusive list implementations. It does require some hackery, however.</p> <p>Boost intrusive structures use the following (and yes, it is implementation specific)</p> <pre><code>template&lt;class Parent, class Member&gt; inline const Parent *parent_from_member(const Member *member, const Member Parent::* ptr_to_member) { return (const Parent*)((const char*)member - offset_from_pointer_to_member(ptr_to_member)); } template&lt;class Parent, class Member&gt; inline std::ptrdiff_t offset_from_pointer_to_member(const Member Parent::* ptr_to_member) { //The implementation of a pointer to member is compiler dependent. #if defined(BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER) //msvc compliant compilers use their the first 32 bits as offset (even in 64 bit mode) return *(const boost::int32_t*)(void*)&amp;ptr_to_member; //This works with gcc, msvc, ac++, ibmcpp #elif defined(__GNUC__) || defined(__HP_aCC) || defined(BOOST_INTEL) || \ defined(__IBMCPP__) || defined(__DECCXX) const Parent * const parent = 0; const char *const member = reinterpret_cast&lt;const char*&gt;(&amp;(parent-&gt;*ptr_to_member)); return std::ptrdiff_t(member - reinterpret_cast&lt;const char*&gt;(parent)); #else //This is the traditional C-front approach: __MWERKS__, __DMC__, __SUNPRO_CC return (*(const std::ptrdiff_t*)(void*)&amp;ptr_to_member) - 1; #endif } </code></pre> <p>Essentially the same thing (albeit in C) as is done in the linux kernel to manage intrusive lists, with the container_of macro (but of course ptr-to-members are not used):</p> <pre><code>#define container_of(ptr, type, member) ({ \ const typeof( ((type *)0)-&gt;member ) *__mptr = (ptr); (type *)( (char *)__mptr - offsetof(type,member) );}) </code></pre>
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