Re: HPUX C++ ABI

[Stan Shebs <shebs at apple dot com>]

Mark Mitchell wrote:

> I've been talking to folks at HP about the C++ ABI in aCC.
>
> They implemented the C++ ABI in aCC using earlier versions of the ABI
> spec.  Due to changes in the spec, and a few mistakes, aCC doesn't
> match up with G++.  Because aCC is already in production use, they don't
> want to make changes to aCC.  But, they do want people to mix G++ and
> aCC objects.
>
> The solution HP is proposing is to make HPUX-only tweaks to the C++ ABI
> in G++ so that on HPUX G++ behaves like aCC.
>
> This is a big project, but nowhere near as big a project as (say)
> implementing Sun's C++ ABI in G++; aCC is an "almost-compliant"
> compiler in much the same way that G++ is.
>
> I believe we should accept these patches, with three caveats:
>
>  (1) We are convinced that they cannot possibly affect the ABI on
>      other platforms.
>
>  (2) We do not take responsibility for making sure they continue
>      to work; our responsibility is to maintain the main ABI.
>
>  (3) The patches do not so complicate the front end as to make us
>      nervous about our ability to understand what is going on.
>
> There is a slippery slope argument that "everyone else will want us to
> support there variant of the ABI too".  But, there is no everyone else;
> HP is the only vendor with an installed base that does not feel they
> can make changes to their ABI.
Well, you'd be opening the door for those nut cases at Apple to want
all of their nasty ABI hacks in FSF GCC too, and we have a way
bigger installed base than HP :-)  Decloning of structors is just
the tip of the iceberg, bwahahaha....

But speaking seriously, we Appleites deal with corporate pressure
to support various hacks by maintaining our own version of GCC and
taking on all the costs that go with that, so I'm wondering why it
is that HP can't do the same.  While I personally don't have a problem
doing a little favor for HP, it's going to be really tricky to avoid
charges of favoritism and bias later on if, say, some Apple feature is
shot down.

Stan