On 12/19/13 16:17, Jan Kundrát wrote:
> On Thursday, 19 December 2013 10:18:55 CEST, Michał Górny wrote:
>> Would it be possible to have a consistent ABI for both C++03 and C++11?
>> The simpler changes like adding new fields can be backported quite
>> easily (even if it would mean having dummy fields in C++03), I have no
>> idea about the more complex changes.
>
> I don't know, but from a bystander's point of view, I surely hope that
> it will be possible. Otherwise there would be no option but providing
> a multilib-like setup for C++11, after all.
>
> Some messages on gcc's ML indicate that there are software vendors who
> are *very* afraid of doing the SONAME change again. Given that C++11
> forbids a refcounted std::string while libstdc++ currently use just
> that for its implementation, I suspect that the upstream developers
> have a very interesting problem to solve. (And there's much more.)
>
> It is pretty clear to me that even the gcc people have not reach a
> consensus on how the ABI of the standard library will look like in
> 4.9, so maybe it is premature for us to talk about how to solve this.
> The ball is on their side.
>
>> Well, if they considered the C++11 ABI in gcc-4.9 stable, we could
>> consider changing the default to C++11. Then, we could do our
>> bump/switch thing as a matter of gcc-4.9 upgrade problem.
>
> To put things into perspective, *if* the ABI changes and if the new
> version is compatible between C++98 and C++11, then we're talking
> something very similar to an upgrade from GCC 3.3.
>
> Cheers,
> Jan
>
just a question, what would do -fabi-version=6 added to CXXFLAGS even
w/o C++11?
