[petsc-users] Is this a bug? MatMultAdd_SeqBAIJ_11

[Daniel Stone]

Hello,

If we look at lines 2330-2331 in file baij2.c, it looks like there are some
mistakes in assigning the `sum..` variables to the z array, causing
the function MatMultAdd_SeqBAIJ_11() to not produce the correct
answer.

I don't have a good example program to demonstrate this yet - it's
currently causing problems in a dev branch of pflotan_ogs that
can produce blocksize 11 matrices. When in parallel, a standard
matrix-vector multiplication calls MatMultAdd for the off-proc
contributions, and the result is wrong when this is redirected
to MatMultAdd_SeqBAIJ_11. Seems to be the root cause of
several solvers failing such as fgmres.

Can anyone confirm that these two lines seem incorrect?


Thanks,

Daniel
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