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Description of problem:
It appears that gcc in FC3 miscompiles numerical code. 
The problem appears to be with lapack libraries and can be
demonstrated with octave (which uses them):

[dima@localhost ~]$ octave
GNU Octave, version 2.1.57 (i686-pc-linux-gnu).
Copyright (C) 2004 John W. Eaton.
....

octave:1> a=rand(100);
octave:2> tic; eig(a); toc
error: dgeev failed to converge
octave:2>
---------------
Sometimes it just hangs there for few minutes after which I kill it.
I tried to compile octave myseelf agains ATLAS (different, optimized
blas/lapack implementation) libraries, which I compile myself as well.
The result was the same. I also tried different versions of octave.

This al works on RHEL3, RH9, FC2, FC1. 

It is possible that the problem is actually with glibc. I was not able
to recompile octave with gcc33 to check that.


Version-Release number of selected component (if applicable):
gcc version 3.4.2 20041017 (Red Hat 3.4.2-6.fc3)

How reproducible:
Always

Steps to Reproduce:
1. start octave
2. type at the octave prompt as shown
3.
    

Actual Results:  octave hangs or gives an error 

Expected Results:  "0.004" (may vary slightly) -- this is 4 msec that
it took the code to run on FC2.

Additional info:

this is on athlon/xp 2000MHz/500Meg.