Re: C++ ABI RFC [was Re: C++/libiberty PATCH for many mangling fixes (6057, 48051, 50855, 51322, etc)]

[Jonathan Wakely <jwakely dot gcc at gmail dot com>]

On 12 January 2012 21:03, Jason Merrill wrote:
> On 01/12/2012 03:17 PM, Jonathan Wakely wrote:
>>
>> And if we are going to do that, shouldn't it be ASAP? Otherwise we'll
>> not be able to change anything significant in .so.7 once it's
>> available in 4.7 and we'll have to create a .so.8 for more changes..
>
>
> Wait, what? ?Are you planning to move to .so.7 in 4.7?

Nope, but the default is still v6, but configuring with
--enable-symvers=gnu-versioned-namespace causes the library to be
built as .so.7 (see the fix for PR 48698), so users of 4.7 will be
able to build a .so.7 and there's no way to put that cat back in the
bag once it's out.

But maybe I've misunderstood the plan for v7 w.r.t versioned
namespaces, and I've just realised that with versioned namespaces
enabled we could have a .so.7 that includes both std::__7::foobar and
std::__8::foobar, without needing to bump the library to .so.8