Update edm::bit_cast [14.0.x]

[fwyzard]

PR description:

Update edm::bit_cast to use std::bit_cast in C++20 mode, otherwise fall back to __builtin_bit_cast if available.

PR validation:

None.

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:

Backport of #45166 to 14.0.x for data taking, using the same branch.

[fwyzard]

backport #45166

[fwyzard]

please test

[cmsbuild]

A new Pull Request was created by @fwyzard for CMSSW_14_0_X.

It involves the following packages:

• FWCore/Utilities (core)

@smuzaffar, @Dr15Jones, @makortel can you please review it and eventually sign? Thanks.
@felicepantaleo, @missirol, @wddgit, @makortel this is something you requested to watch as well.
@rappoccio, @antoniovilela, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

• Backported from Update edm::bit_cast #45166

[cmsbuild]

cms-bot internal usage

[cmsbuild]

-1

Failed Tests: UnitTests
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-a6db41/39842/summary.html
COMMIT: c619df6
CMSSW: CMSSW_14_0_X_2024-06-11-1100/el8_amd64_gcc12
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/45200/39842/install.sh to create a dev area with all the needed externals and cmssw changes.

Unit Tests

I found 1 errors in the following unit tests:

---> test RecoPPSLocalNewT2 had ERRORS

Comparison Summary

Summary:

• You potentially added 3 lines to the logs
• Reco comparison results: 45 differences found in the comparisons
• DQMHistoTests: Total files compared: 48
• DQMHistoTests: Total histograms compared: 3338712
• DQMHistoTests: Total failures: 3
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3338689
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 47 files compared)
• Checked 202 log files, 165 edm output root files, 48 DQM output files
• TriggerResults: no differences found

[fwyzard]

ignore tests-rejected with ib-failure

[Dr15Jones]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_14_0_X IBs (test failures were overridden) and once validation in the development release cycle CMSSW_14_1_X is complete. This pull request will now be reviewed by the release team before it's merged. @sextonkennedy, @antoniovilela, @rappoccio (and backports should be raised in the release meeting by the corresponding L2)

[rappoccio]

+1

[rappoccio]

merge