Hi,
I'm getting a segmentation violation error when I use
DMCompositeGetISLocalToGlobalMappings on a DMComposite defined redundantly
on subsets of the PETSC_COMM_WORLD. I could reproduce the error in the
small code you can find here attached. It creates a PetsSubcomm from
PETSC_COMM_WORLD, then it defines a DMDA on the Subcomm->comm and finally
it packs it into a DMComposite.
I get this error whenever I call DMCompositeGetISLocalToGlobalMapping on a
DMComposite defined in such a way.

I would be glad if you could give it a look.
Thank you
Domenico