Re: C++11 and librados C++

[Alex Elsayed <eternaleye@gmail.com>]

Sage Weil wrote:

> On Tue, 4 Aug 2015, Wido den Hollander wrote:
>> On 03-08-15 22:25, Samuel Just wrote:
>> > It seems like it's about time for us to make the jump to C++11.  This
>> > is probably going to have an impact on users of the librados C++
>> > bindings.  It seems like such users would have to recompile code using
>> > the librados C++ libraries after upgrading the librados library
>> > version.  Is that reasonable?  What do people expect here?
>> 
>> Well, some people use Qemu build by their distro, but they use librados
>> / librbd from ceph.com
>> 
>> So if they suddenly have to rebuild Qemu that would hurt them I think.
> 
> Qemu fortunately is using the C bindings, so it would not be affected.
> It is only the C++ ABI (or lack thereof) that is problematic.
> 
> What users of the C++ bindings are there out there?

One thing I think is worth noting: GCC 5 represents an ABI break for C++11 
http://developerblog.redhat.com/2015/02/05/gcc5-and-the-c11-abi/

Thus, some serious care is needed to avoid compat hazards when using C++11.