On 2/26/2012 7:04 AM, Simon wrote:
On 26/02/2012 03:22, Walter Bright wrote:
On 2/25/2012 4:01 PM, Simon wrote:
On 25/02/2012 22:55, Walter Bright wrote:
Enter C++'s shared_ptr. But that works by, for each object, allocating a
*second* chunk of memory to hold the reference count. Right off the bat,
you've got twice as many allocations & frees with shared_ptr than a GC
would have.
http://www.boost.org/doc/libs/1_43_0/libs/smart_ptr/make_shared.html
so you don't have to have twice as many allocations.
There are many ways to do shared pointers, including one where the
reference count is part of the object being allocated. But the C++11
standard share_ptr does an extra allocation.
The stl one is based on boost, so it has make_shared as well:
http://en.cppreference.com/w/cpp/memory/shared_ptr
and it's in vs 2010
http://msdn.microsoft.com/en-us/library/ee410595.aspx
Not that I'm claiming shared pointers are superior to GC.
At the GoingNative C++ conference, the guy who is in charge of STL for VS said
that it did an extra allocation for the reference count.
