On 08/23/13 02:41, Thorsten Ottosen wrote:
On 23-08-2013 04:54, Ben Pope wrote:
But how can you be sure an arbitrary non-POD object in the vector doesn't hold a pointer to itself?
Also, this problem has just been found in Folly fbvector: https://github.com/facebook/folly/issues/35
WE can't, hence we need to call copy/move constructors via the virtual functions.
-Thorsten
The attached code show a non-POD object containing a raw pointer to itself and an offset_ptr to itself. It also shows an in-place construction of such a non-POD object in a "from" std::vector<char>. Then a COPY CTOR of another "to" std::vector<char>. The printouts (also attached) show that the raw_ptr has wrong value in the "to" but the offset_ptr has the correct value. AFAICT, this shows the offset_ptr would solve the problem of moving the storage in case the storage needs to be resized. Am I missing something? -Larry