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[QUOTE="Bo Persson, post: 2933849"]
JohnQ wrote:

::: Perhaps, but it's not defined in C++. Of more direct relevance to
::: the OP though is that, regardless of whether we're all happy with
::: that definition of "bitwise copy", it's not what happens in the
::: implicitly- defined copy constructor, which does a memberwise
::: copy.
::
:: That's interesting. Apparently "a struct is a struct" hardly ever!
:: Oh wait, does C do memberwise copy of structs also or bitwise?

In C there is not much of a difference!

Here's something else:

In C and C++, the *compiler* is allowed to do a bitwise copy whenever 
it knows that it will work (and is better in some way). This means 
that the compiler generated copy constructor and assignment operator 
might look like a memcpy (or better!), even for a non-POD class.

It is just you, the programmer, that cannot do this, because there are 
no guarantees in the standard that it will work always. The compiler 
knows all the special cases, and is allowed to take advantage of this 
knowledge.

Bo Persson
[/QUOTE]

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