cvs commit: src/include string.h src/lib/libc/string Makefile.inc memchr.3 memrchr.c src/sys/sys param.h

[Daniel Eischen]

On Wed, 28 May 2008, David Schultz wrote:

> On Wed, May 28, 2008, Daniel Eischen wrote:
>> On Wed, 28 May 2008, David Schultz wrote:
>>
>>> On Wed, May 28, 2008, Daniel Eischen wrote:
>>>> No, all new symbols in 8-current go into FBSD_1.1, not 1.2.  The
>>>> only time we go to 1.2 is when 8.x branches to 9.0.  If for some
>>>> reason memrchr() were to change its ABI, then we would go to 1.1.1
>>>> in -current for the ABI change and any subsequent new symbols, and
>>>> the MFC to 7.x would also be 1.1.1.
>>>>
>>>> It is ok for a FBSD_1.1 in -current to be a superset of FBSD_1.1
>>>> in a previous branch.  In fact you can't prevent them from being
>>>> different unless you mandate that all new symbols get MFC'd to
>>>> their respective namespaces in previous branches.
>>>
>>> Perhaps I misinterpreted what you said about this last year, but I
>>> thought you said you didn't want symbols added to existing
>>> namespaces in -STABLE. In 7.X, why would it be okay to add new
>>> symbols to FBSD_1.1 between releases but not to FBSD_1.0?
>>
>> I think you're just off by a version.  -stable didn't have
>> FBSD_1.1, so we just _did_ add memrchr() to a _new_ namespace
>> in -stable.
>
> Yes, yes, that's fine, that's what I said. But you also said it's
> fine to add things to FBSD_1.1 in 7.X, which I think is different
> from what you told me last year...
>
> In practice, this means that if a binary uses FBSD_1.0 and
> FBSD_1.1 symbols, the only thing you can say with confidence is
> that it will run in 8.0-RELEASE. That's fine with me; I'd just
> like to make sure I understand what you do and don't intend to
> guarantee.

Yes, we decided not to bump versions every time we add a new
symbol or ABI change.  But we can also record a set of symbols
(in a file) for each release, and make some sort of ABI checker
that can tell under what releases an application will run.

-- 
DE