[Libguestfs] Any risk in sparsifying a base image (that has a snapshot on top of it)

Assuming the VM is not running, and we have a base (raw, sparse) with a snapshot (qcow2) on top of it. Is there any issue with running virt-sparsify on the base image? I assume deleted blocks in the base can be sparsified, since they are either still deleted on the snap (which is fine) or were written in the snap (which is fine either and does not change or matter for the base image). Can I assume sparsifying should not make any changes that matter for a VM that will be spun (post the process)? TIA, Y.