Patrick Sanan <patrick.sa...@gmail.com> writes: > Sorry about the delay on this. I can reproduce. > > This regression appears to be a result of this optimization: > https://gitlab.com/petsc/petsc/-/merge_requests/4273
Thanks for tracking this down. Is there a reason to prefer preallocating twice ierr = MatPreallocatorPreallocate(preallocator,PETSC_TRUE,A);CHKERRQ(ierr); ierr = MatPreallocatorPreallocate(preallocator,PETSC_TRUE,A_duplicate);CHKERRQ(ierr); versus using MatDuplicate() or MatConvert()?