On Tue, Mar 6, 2012 at 09:52, Klaij, Christiaan <C.Klaij@marin.nl> wrote:
>Could you get a stack trace with gdb? Also, I ran on petsc-dev.

Breakpoint 1, vecsumsegv::vecsumsegv (this=0x7fffffffd310, m=3, n=4)
   at vecsumsegv.cc:28
28        ierr = VecSum(x,&val);
(gdb) next

This was fixed in petsc-dev.

http://petsc.cs.iit.edu/petsc/petsc-dev/rev/3b9bc425b217


Why are you using VecNest? It causes more harm than good in all but some very special circumstances.