As the comment in the linked BF describes, a stepdown could interrupt a running dropDatabase and leave the dropPending true on that database.
- is duplicated by
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SERVER-40730 renameCollection within dropCollection causes signal: 11 (Segmentation fault)
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 - Closed
 
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- is related to
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SERVER-40306 Lock acquisition in dropDatabase cmd can throw and leave the database with drop-pending set to true
-         
 - Closed
 
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