Added missing cmath header to GBRForest

[Dr15Jones]

Needed cmath for exp function.

NOTE: this fixes the compiler errors seen in the DEVEL build.

[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-25085/7081

[cmsbuild]

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

It involves the following packages:

CondFormats/EgammaObjects

@tocheng, @cmsbuild, @franzoni, @ggovi, @pohsun, @lpernie can you please review it and eventually sign? Thanks.
@mmusich, @tocheng, @seemasharmafnal this is something you requested to watch as well.
@davidlange6, @slava77, @fabiocos you are the release manager for this.

cms-bot commands are listed here

[Dr15Jones]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/31419/console Started: 2018/11/01 15:24

[Dr15Jones]

@fabiocos @smuzaffar this fixes the compilation problems seen in the DEVEL IB.

[cmsbuild]

+1
Tested at: 6beb6f6
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-25085/31419/summary.html

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:
6dd1cfe
28a2116
2ca6719
1e8121c
3096cab
11d5121
You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-25085/31419/git-log-recent-commits
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-25085/31419/git-merge-result

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-25085/31419/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 32
• DQMHistoTests: Total histograms compared: 2993155
• DQMHistoTests: Total failures: 24
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2992934
• DQMHistoTests: Total skipped: 197
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 31 files compared)
• Checked 134 log files, 14 edm output root files, 32 DQM output files

[fabiocos]

@Dr15Jones I would expect that the differences (mostly in L1T but not the usual ones) have nothing to do with this PR. @lpernie @tocheng @ggovi could you please sign?

[fabiocos]

The problem was introduced by the recent merge of #24432 in https://github.com/cms-sw/cmssw/pull/24432/files#diff-6c5b8b2e5e434ddb757c1b57ab5aca0b
@smuzaffar I noticed an error reported in the header check #24432 (comment) , but as usual it was obscure, and not affecting this file...

[smuzaffar]

@fabiocos , problem is due to boost version. We were getting this (cmath) header indirectly from boost. In DEVEL IBs we have boost 1.67.0 they have remove some unneeded includes that is why we only see this failure in DEVEL IBs. header consistency check should not have caught this as cmath was indirectly visible via boost headers.

[fabiocos]

@smuzaffar thanks for the clarification

[pohsun]

+1

[fabiocos]

@ggovi could you please check and sign it?

[smuzaffar]

@ggovi , can you please sign this. This is breaking DEVEL IBs.

[ggovi]

+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. @davidlange6, @slava77, @smuzaffar, @fabiocos (and backports should be raised in the release meeting by the corresponding L2)

[fabiocos]

+1