Re: [boost] [shifted_ptr] "new shifted<T>"

From: Phil Bouchard (philippe_at_[hidden])
Date: 2008-06-09 04:59:34

"Phil Bouchard" <philippe_at_[hidden]> wrote in message 
news:g2b1pp$pir$1_at_ger.gmane.org...
> Ok I just added a skeleton for a STL compliant allocator called 
> "shifted_allocator" in "sh_owned_base_nt.hpp" of my sandbox.  This is an 
> example of how it should be written, unfortunately I wasn't able to make 
> it compile but this is basically the final step.  There are some FIXME in 
> the header and shifted_ptr_test2.cpp file.

Now I added a PowerPoint presentation comparing the pointer with all other 
existing memory managers out there:
sandbox/shifted_ptr/libs/example/doc/ShiftedPointer.ppt

While writing it I came to realize the mark & sweep algorithm is deleting 
objects even if they are still parent of an object still being referenced 
from the stack.  Suppose for example I got a widget having a std::string as 
a member.  This means if the stack refers to the buffer of the string but 
nobody points to the widget anymore then the string buffer will be deleted 
and thus a segfault will occur.

On the other hand one feature I really like from the garbage collector is 
that one might use it to silently replace all malloc() and free() from an 
existing C project without the need to rewrite any code.  I think this is a 
nice feature and I would encourage people using it more in that matter.

Thanks,
-Phil