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Re: State of gcc 2.95 use in Debian unstable

thanks for all the comments. I will do tests with gcc-4.x and, if the
regression is still there, file a bug report upstream.


On Saturday 10 December 2005 20:03, Thiemo Seufer wrote:
> Heiko Müller wrote:
> > Dear Thiemo,
> > we very much appreciate your work on the gcc-2.95 debian package.
> > For us - and probably also for other users in the scientific
> > community - the "old" compiler version is still of great value.
> >
> > We use gcc-2.95 to compile C/C++ code with very large mathematical
> > expressions generated by computer algebra software. This involves
> > very long (several thousand lines of code) functions to evaluate
> > multi-variable polynomial expression resulting from perturbation
> > theoretical solutions of physical problems.
> >
> > We found that gcc-2.95 -Os produces object code of acceptable quality
> > within reasonable compilation times. gcc >=3 is less efficient w.r.t.
> > compilation time and memory consumption and in many cases even fails
> > to compile our codes due to the very long expressions. The C/C++ codes
> > generated from the computer algebra software are perhaps unusual but
> > not broken.
> Well, gcc 3.x was somewhat disappointing WRT, but I would expect 4.0
> to do better. If 4.x fails for your (valid and standard-conforming)
> code, please consider to provide a testcase to the upstream developers.
> I'm sure they are interested in it, and long-term it will help you as
> well to have a more modern compiler which can handle such cases.
> > Since what we are doing is not so unusual in theoretical physics we are
> > probably not alone with these kind problems. Please consider that even
> > if no other debian packages would depend on gcc-2.95 many users may
> > very much require it.
> Indeed, I got also one private reply which suggested gcc-2.95 is still
> an interesting choice for some numerics code.
> Thiemo

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