Change the default optimisation level to -O3

[fwyzard]

No description provided.

[cmsbuild]

A new Pull Request was created by @fwyzard for branch IB/CMSSW_14_1_X/master.

@smuzaffar, @aandvalenzuela, @cmsbuild, @iarspider can you please review it and eventually sign? Thanks.
@sextonkennedy, @antoniovilela, @rappoccio you are the release manager for this.
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[cmsbuild]

cms-bot internal usage

[fwyzard]

test parameters:

• full_cmssw = true
• enable = threading

[fwyzard]

please test

[fwyzard]

Now that CMSSW_14_1_0_pre4 has been built, we can merge this in the master branch.

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-680ea8/39521/summary.html
COMMIT: dd72101
CMSSW: CMSSW_14_1_X_2024-05-24-1100/el8_amd64_gcc12
Additional Tests: THREADING
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmsdist/9205/39521/install.sh to create a dev area with all the needed externals and cmssw changes.

[smuzaffar]

+externals

this has been tested in Geant4 IBs

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next IB/CMSSW_14_1_X/master IBs after it passes the integration tests. This pull request will now be reviewed by the release team before it's merged. @rappoccio, @antoniovilela, @sextonkennedy (and backports should be raised in the release meeting by the corresponding L2)