Hello

Build Date & Platform: XP 3.4RC1 Libo BuildID = 340m1 (Build: 11)

Steps to reproduce:
- Define a name through Insert> Name> Define for a data range
- Create a pivot table based on this user name
- Insert> Name> Define> Delete this user name
- Update the pivot table 

Expected result: Replace the values in the pivot table by #NAME?
Actual result : Crash

The attached spreadsheet already contains a pivot table based on a named range for an easy reproduction of the crash:
- Open the attached file
- Insert> Names> Define> "PysData"> Delete
- Right click on the pivot table > update

Additional Information: Reproduced with same build & platform on [fr-discuss]

Best regards