[SIM] Added Geant4 mag field stepper type

[civanch]

PR description:

Attempt to fix cms-sw/cmsdist#9989
Pure technical.

PR validation:

private

If this PR is a backport please specify the original PR and why you need to backport that PR. If this PR will be backported please specify to which release cycle the backport is meant for: NO

[cmsbuild]

cms-bot internal usage

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-48665/45682

[cmsbuild]

A new Pull Request was created by @civanch for master.

It involves the following packages:

• SimG4Core/MagneticField (simulation)

@civanch, @cmsbuild, @kpedro88, @mdhildreth can you please review it and eventually sign? Thanks.
@bsunanda, @fabiocos, @makortel, @martinamalberti, @namapane, @rovere, @slomeo this is something you requested to watch as well.
@antoniovilela, @mandrenguyen, @rappoccio, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

[civanch]

please test

[cmsbuild]

+1

Size: This PR adds an extra 16KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-3333a3/47519/summary.html
COMMIT: e967e62
CMSSW: CMSSW_15_1_X_2025-08-04-1100/el8_amd64_gcc12
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/48665/47519/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially added 2 lines to the logs
• Reco comparison results: 3 differences found in the comparisons
• DQMHistoTests: Total files compared: 50
• DQMHistoTests: Total histograms compared: 4076122
• DQMHistoTests: Total failures: 22
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4076080
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 49 files compared)
• Checked 215 log files, 184 edm output root files, 50 DQM output files
• TriggerResults: no differences found

[civanch]

+1

[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. @antoniovilela, @sextonkennedy, @mandrenguyen, @rappoccio (and backports should be raised in the release meeting by the corresponding L2)

[smuzaffar]

@civanch , looks like this is not enough for geant4 ref7. CMSTDormandPrince45 class also inherits from G4MagIntegratorStepper so that class also need the same fix.

I think you also need to include G4Version.hh for before using G4VERSION_NUMBER

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-48665/45693

[cmsbuild]

Pull request #48665 was updated. @civanch, @cmsbuild, @kpedro88, @mdhildreth can you please check and sign again.

[iarspider]

please test

[cmsbuild]

+1

Size: This PR adds an extra 16KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-3333a3/47536/summary.html
COMMIT: d049a42
CMSSW: CMSSW_15_1_X_2025-08-05-1100/el8_amd64_gcc12
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/48665/47536/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 2 lines from the logs
• Reco comparison results: 5 differences found in the comparisons
• DQMHistoTests: Total files compared: 50
• DQMHistoTests: Total histograms compared: 4076122
• DQMHistoTests: Total failures: 64
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4076038
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 49 files compared)
• Checked 215 log files, 184 edm output root files, 50 DQM output files
• TriggerResults: no differences found

[civanch]

+1

[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. @sextonkennedy, @antoniovilela, @mandrenguyen, @rappoccio (and backports should be raised in the release meeting by the corresponding L2)

[mandrenguyen]

+1