On Thu, Sep 25, 2003 at 06:17:23PM +0800, John Summerfield wrote:
> On Wed, 24 Sep 2003, Arnd Bergmann wrote:
>
> > On Wednesday 24 September 2003 11:11, John Summerfield wrote:
> > > I'm not familiar with SuSE, but I woul;d guess that if binaries created
> > > on S7 run on S8 and RHL 7, then they should also run on RHL 8.
> >
> > Only if you avoid C++ or link statically against libstdc++ as mandated by
> No.
> Red Hat historically has provided compatibility libraries so that
> software compiled on RHL n.x runs on o.x where o.x is the next major
> series of releases after n.x.
>
> If software from SuSE 7.x runs on RHL 7.x (as somone else said), then it
> ought also run on RHL 8.0 if the same compatibility libraries needed to
> support RHL 7.x apps on 8.0 are in place.
All the above is true. I think Linux is providing a really huge support for
backwards compatibility. If you look at how much has changed between
Red Hat Linux 7.x, 8.x, 9 and our current Red Hat Enterprise 3 release,
things have changed dramatically. Look at glibc, kernel, ncurses and
libs like libstdc++ where all developers agree that it is impossible to
provide a stable ABI/API, still ISV vendors want to depend on this lib.
Look at examples:
- Some ISV Software is still depending on ncurses4, while we have changed that
for Red Hat Linux into a compat rpm in 2000:
* Sun Jun 11 2000 Bill Nottingham <[EMAIL PROTECTED]>
- build compat package
We have included this compat rpm until RHL9, but have decided to drop
this from RHEL3.
- Our RHEL3 mainframe release contains a compat-llibstdc++ rpm that needs
it own version of gcc-2.95.3 to build it. We include a new compiler to
build one compat package and Red Hat has never shipped this specific
compiler in other products apart from mainframe.
So there is really huge efford to keep things running and given the speed
of Linux development and e.g. you will not find guaranteed support for
libstdc++, the reality is not that bad.
Also you can often keep the compat rpms running even longer. Please look
at the last release we have shipped libc5 libs on x86 and you can still
run them on RHL9 with some ancient ISV software. No additional hacking
needed, but we have officially stopped giving support for this setup from
Red Hat.
The other question is: Does it make sense for ISVs to depend on libstdc++?
I'd say it does not, but heard different opinions on this in the past. ;-)
greetings,
Florian La Roche
P.S.: Excuse for mentioning x86 on this list, but my mainframe engagement
did not allow me to forget about other archs yet.
