In Vivado 2012.2, the Vivado IDE or PlanAhead Project Manager will terminate unexpectedly if a user starts to update the IP catalog (Right click in the Vivado IP catalog and select Update IP catalog ...) with a large IP repository and then cancels the operation before the update completes.
In Vivado 2012.3, attempting to cancel an update of the IP catalog has no effect (The Update IP Catalog operation continues).
As seen in the Vivado 2012.2 behavior, cancelling the load of an IP repository in the middle of the operation causes the IP catalog to be in an unstable state.
In Vivado, 2012.3, the cancel operation has been coded to have no effect on the repository loading. The cancel button remains in the Update IP Catalog dialog box as the cancel function is intended to be implemented in a later software version. When it is completely fixed, the cancel function will restore the IP Catalog to the state it had before the Update operation began loading the new repository information.