If you aren't using gpt then you aren't getting the error message and thus aren't related to this bug. That message again was:
Assertion (last_usable <= disk->dev->length) at ../../../libparted/labels/gpt.c:718 in function _parse_header() failed.
If you aren't using gpt then you aren't getting the error message and thus aren't related to this bug. That message again was:
Assertion (last_usable <= disk->dev->length) at ../../. ./libparted/ labels/ gpt.c:718 in function _parse_header() failed.