Re: [cxx-abi-dev] What is a POD? TC1 or first C++ Standard

[Mark Mitchell <mark@xxxxxxxxxxxxxxxx>]

Dennis Handly wrote:

> > GCC is not going to change back to the pre-TC1 definition, even for
> > return values
> >    
> What do you mean by "return values"?  I said it only affects layout.
> I first thought it also affects them but 3.1.4 Return Values, says nothing
> about PODs.
>  
You are correct.  I thought it said that non-PODs could not be 
passed/returned in registers, but, in fact, it is more specific: it 
talks about non-trivial copy constructors and destructors.
That makes things somewhat simpler.

It seems to me that a POD with a pointer-to-member data member should 
not be a "POD for purpose of layout" because the layout of a "POD for 
the purpose of layout" is supposed to be whatever the C ABI would 
require -- and the C ABI does not specify the layout of a type 
containing a pointer-to-member.
Now, the question is, when would this make a difference?  Dennis, can 
you post a small test case showing where the layout is different 
depending on whether you use the TC1 or pre-TC1 definition of POD?
--
Mark Mitchell
CodeSourcery, LLC
(916) 791-8304
mark@xxxxxxxxxxxxxxxx