message: The PetscParMatrix constructor needs to increase the reference count of B
diff: @@ -3322,7 +3322,7 @@ static PetscErrorCode __mfem_pc_shell_setup(PC pc)
  ierr = PCGetOperators(pc,NULL,&B); CHKERRQ(ierr);
  // Call user-defined setup
  - mfem::OperatorHandle hB(new mfem::PetscParMatrix(B,false),true);
  + mfem::OperatorHandle hB(new mfem::PetscParMatrix(B,true),true);
  mfem::PetscPreconditionerFactory *factory = ctx->factory;
  ctx->op = factory->NewPreconditioner(hB);
  ctx->ownsop = true;
  