JQL search involving "labels is empty" no longer works as before

[Sten Kristian Finckenhagen]

For a long time I've successfully been using the JQL search below to find certain Jira issues with missing labels.

project = XXX and issuetype = bug and status not in (rejected,resolved) and (labels not in (TS1,TS2,TS3,TS4,TS5,UAT,REG,OPM) or labels is empty)

Recently, the search stopped working as before and now the result list contains Jira issues with labels that are to be excluded.

After tinkering a bit with the JQL search it seems I get the same result as before if I split the search into two separate searches like this:

project = XXX and issuetype = bug and status not in (rejected,resolved) and labels not in (TS1,TS2,TS3,TS4,TS5,UAT,REG,OPM)

project = XXX and issuetype = bug and status not in (rejected,resolved) and labels is empty

This makes me suspect there's something wrong with the interpretation of the labels is empty statement.

Did Atlassian make changes to the way JQL searches work lately?

[Sten Kristian Finckenhagen · Accepted solution]

Somehow, the original JQL expression is now working again.

I have no idea what happened but like I mentioned in my initial post there was a period when the JQL search didn't work as expected but luckily everything seems to back to normal so I'm happy,

[Aron Gombas _Midori_]

Lame idea: what if you move the logical operators a bit and use some redundancy?

(project = XXX and issuetype = bug and status not in (rejected,resolved) and labels not in (TS1,TS2,TS3,TS4,TS5,UAT,REG,OPM))
or
(project = XXX and issuetype = bug and status not in (rejected,resolved) and labels is empty)

 I know it is ugly, but it may work if Atlassian broke something related to the operator precedence (as you suspect).