[petsc-dev] [petsc-users] MatPreallocatorPreallocate segfault with PETSC 3.16

[Jed Brown]

Patrick Sanan <patrick.sanan at 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()?