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[Lapack] [bug report] dsyevr does not seem to be thread-safe

Dear LAPACK Team, 
according to my testing LAPACKs dsyevr does not seem to be thread-safe. This is 
in contrast to the statement "all routines in LAPACK-3.3 are now thread-safe."  
from "http://www.netlib.org/lapack/lapack-3.3.0.html). 
In multi-threaded application the routine produces (arbitrarily wrong 
eigenvectors, although eigenvalues are ok).

I tried to discuss the problem on http://stackoverflow.com 

http://stackoverflow.com/q/18216314/1458343

where also a full example program is given, which demonstrates the issue. As 
I'm not a Fortran programmer I can only provide an example in C. It was tested 
to call the routine dsyevr via the LAPACKE interface and also directly. After 
the test failed with optimized OpenBLAS, the netlib reference LAPACK/BLAS was 
used to confirm the misbehavior of the program. The tests were run on two 
different platform. 

I assume there is still a bug in LAPACK concerning thread-safety. I would 
appreciate if you could confirm the bug and of course correct it in further 
versions. Contributions to the stackoverflow discussion are also welcome. 

With best regards
Daniel Strobusch


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