C++98/C++11 ABI compatibility for gcc-4.7

[3dw4rd@verizon.net]

 On 06/18/12, Paolo Carlini<paolo.carlini@oracle.com> wrote:
 > 
> ... I suppose that for 4.8.0 we really want to bump the ABI, for many other reasons too, and be done with it.
> 
> Paolo.

Would this bump include everything? Such as rebasing std::ios_base::failure from std::exception to std::system_error and everything else? I think we'd best get the whole thing over with at once.

How is libstdcxx_so_7-2-branch?  Perhaps instead of messing with tr2 I should help here?

Ed