Made pat::MET const thread-safe

[Dr15Jones]

PR description:

Removed use of mutable member in held helper class.

This was found by the static analyzer.

PR validation:

Code compiles.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-38457/30668

• This PR adds an extra 28KB to repository

[cmsbuild]

A new Pull Request was created by @Dr15Jones (Chris Jones) for master.

It involves the following packages:

• DataFormats/PatCandidates (reconstruction)

@jpata, @cmsbuild, @clacaputo can you please review it and eventually sign? Thanks.
@gpetruc, @missirol, @gouskos, @rovere, @hatakeyamak this is something you requested to watch as well.
@perrotta, @dpiparo, @qliphy you are the release manager for this.

cms-bot commands are listed here

[Dr15Jones]

please test

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-fe2183/25675/summary.html
COMMIT: 8c2e888
CMSSW: CMSSW_12_5_X_2022-06-21-1100/el8_amd64_gcc10
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/38457/25675/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• No significant changes to the logs found
• Reco comparison results: 6 differences found in the comparisons
• DQMHistoTests: Total files compared: 50
• DQMHistoTests: Total histograms compared: 3659099
• DQMHistoTests: Total failures: 13
• DQMHistoTests: Total nulls: 1
• DQMHistoTests: Total successes: 3659063
• DQMHistoTests: Total skipped: 22
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.004 KiB( 49 files compared)
• DQMHistoSizes: changed ( 312.0 ): 0.004 KiB MessageLogger/Warnings
• Checked 208 log files, 45 edm output root files, 50 DQM output files
• TriggerResults: no differences found

[clacaputo]

Just for my understanding, removing these fields (up to line 300) doesn't break back compatibility? What does transient="true" supposed to do? Thanks

[Dr15Jones]

Just for my understanding, removing these fields (up to line 300) doesn't break back compatibility?

I believe that to be correct.

What does transient="true" supposed to do?

It tells ROOT not to store those variables. This is why dropping them from the class doesn't affect read back of old files.

[clacaputo]

+reconstruction

• technical PR
• no reco changes

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @perrotta, @dpiparo, @qliphy (and backports should be raised in the release meeting by the corresponding L2)

[perrotta]

+1