This is the mail archive of the gcc-bugs@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[Bug fortran/5900] [g77 & gfortran] Lapack regressions since g77 2.95.2


------- Additional Comments From Thomas dot Koenig at online dot de  2005-01-20 10:58 -------
The Lapack installation hints under
http://www.netlib.org/lapack/html/installation.hints
show that some adjustment was necessary for Crays because

# 1. The Cray compilers implement a complex divide without scaling.  To run
#    the complex linear equation tests on the T3D, I had to modify SLABAD to
#    take the square root of overflow and underflow.  I ran the eigenvalue
#    tests with the default version of SLABAD. 

Currently, gcc also uses a naive complex division algorithm without
scaling, see PR 18092.  This may be the cause of a lot of the complex
LAPACK failures.  Unfortunately, this is not easily changed, because
the scaled algorithm is currently broken, see PR 19486.

        Thomas

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=5900


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]