On May 7, 2012, at 11:18 AM, Matthew Knepley wrote:

On Mon, May 7, 2012 at 11:53 AM, Satish Balay <[email protected]> wrote: On Mon, 7 May 2012, Barry Smith wrote:

...

I am also running complex.

Look in the file dlasq2.f (it will be in the externalpackages subdirectory of the PETSc directory. Look at line 215, this is where valgrind has a problem. In my copy

END IF * * Check for negative data and compute sums of q's and e's. * <------ this is line 215 Z( 2*N ) = ZERO

it is a comment, which is not good. Is lione 215 also a comment in your copy of dlasq2.f?

There are two possible causes I can think of for your problem

1) PETSc does not allocate enough work space for zgesvd() or 2) the BLAS/LAPACK routines have a bug where they sometimes access out of their work space.

Satish,

Can you try the same build options on a Linux machine as close to Alexander as we have and see if you can reproduce this?

I can reproduce on my linux laptop. [also on petsc.mcs]

Are we forgetting the factor 2 on the workspace?

No because we are pure complex so all our mallocs are with respect to complex. I looked through the docs for the lapack routine and it looks like we are allocating enough. But. Satish, Can you bring your laptop up and we'll see if we can track down the problem? Thanks Barry

Matt

Satish -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener