Yuval Ronen wrote:
Hi, I'm new to boost, so this post might seem silly to some of you, and I apologize if this is the case.
I have a tiny performance suggestion:
The c'tor
template<class Y> shared_ptr(shared_ptr<Y> const & r, detail::dynamic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn) { if(px == 0) // need to allocate new counter -- the cast failed { pn = detail::shared_count(); } }
should be changed to:
template<class Y> shared_ptr(shared_ptr<Y> const & r, detail::dynamic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(px ? r.pn : detail::shared_count()) { }
Good suggestion. Unfortunately Borland 5.5.1 seems to have trouble with the pn( px? r.pn: detail::shared_count() ) initialization, and the performance gains aren't worth the #ifdef in this case, IMO.