[rootcling] Construct options after resetting parser

[stephanlachnit]

This Pull request:

Construct the llvm::cl options in the main function and reset the parser before. This removes any predefined options registered by LLVM (see llvm::cl docs).

Changes or fixes:

Allows building with vanilla LLVM, see also #12156 (comment)

Checklist:

• tested changes locally
• updated the docs (if necessary)

This PR fixes #12156

Note on clang-format: the entire file is very clang-format unclean. I tried my best to make it look readable, if you want to clang-format it I would propose to do it separately as it changes almost every line in the file.

[phsft-bot]

Starting build on ROOT-debian10-i386/soversion, ROOT-performance-centos8-multicore/cxx17, ROOT-ubuntu2204/nortcxxmod, ROOT-ubuntu2004/python3, mac11/noimt, mac12arm/cxx20, windows10/default
How to customize builds

[phsft-bot]

Build failed on ROOT-ubuntu2004/python3.
See console output.

[phsft-bot]

Starting build on ROOT-debian10-i386/soversion, ROOT-performance-centos8-multicore/cxx17, ROOT-ubuntu2204/nortcxxmod, ROOT-ubuntu2004/python3, mac11/noimt, mac12arm/cxx20, windows10/default
How to customize builds

[phsft-bot]

Build failed on ROOT-ubuntu2004/python3.
See console output.

[phsft-bot]

Build failed on mac11/noimt.
Running on macphsft20.dyndns.cern.ch:/Users/sftnight/build/workspace/root-pullrequests-build
See console output.

Failing tests:

• projectroot.roottest.python.distrdf.dask.roottest_python_distrdf_dask_test_all

[github-actions]

Test Results

         7 files           7 suites   1d 20h 58m 43s ⏱️
  2 476 tests   2 475 ✔️ 0 💤 1 ❌
16 583 runs  16 582 ✔️ 0 💤 1 ❌

For more details on these failures, see this check.

Results for commit 33df5ac.

[Axel-Naumann]

Aren't we relying on some LLVM options that rootcling does not declare explicitly, and that we would lose by resetting the options, iiuc? @vgvassilev ?

[vgvassilev]

As I have mentioned in the original issue, this is not a direction I’d like to go. It does not fix the original issue and seems to deviate from the way llvm suggests using the command line options.

[phsft-bot]

Build failed on ROOT-debian10-i386/soversion.
Running on pcepsft11.dyndns.cern.ch:/home/sftnight/build/workspace/root-pullrequests-build
See console output.

Failing tests:

• projectroot.roottest.root.io.json.roottest_root_io_json_make

[Axel-Naumann]

@stephanlachnit given your progress in understanding the root cause in the other issue are you okay with closing this PR?

[stephanlachnit]

@stephanlachnit given your progress in understanding the root cause in the other issue are you okay with closing this PR?

I haven't yet checked this - I will close it once I confirmed it works with static system libs as well.

[stephanlachnit]

@stephanlachnit given your progress in understanding the root cause in the other issue are you okay with closing this PR?

I haven't yet checked this - I will close it once I confirmed it works with static system libs as well.

Confirmed that with #13420 this is not needed anymore.