G++ ABI: bug in non-POD class tail-padding reuse?

[Mark Mitchell]

--On Wednesday, November 13, 2002 10:21:22 AM +0100 Gabriel Dos Reis 
<gdr@integrable-solutions.net> wrote:

>
> Hi,
>
>   It has been my understanding that the new ABI reuses tail-padding
> for non-POD class-types.  However the sizeof() displayed for class B,
> defined below, is different from what would have been expected.
>
> More specifically, consider:
>
>     #include <iostream>
>
>     struct A {
>        int i;
>        char c;
>     };
>
>     struct B : A {
>        char c;
>     };

A is a POD, so we cannot reuse its tail padding.  If you throw in a
constructor in A, for example, you'll see that B's size shrinks.

-- 
Mark Mitchell                mark@codesourcery.com
CodeSourcery, LLC            http://www.codesourcery.com