Warning cling

[Ako_b]

First of all, do you still have folder where you built ROOT and, less importantly, source folder? If not, then the only way would be to build from scratch again like you mentioned you did earlier. In such a case I assume it would be reasonable to use latest version (Releases · root-project/root · GitHub).

Regarding simple upgrade, I’m afraid that in your case you have to build from scratch, according to Easy way to update ROOT?:

@eguiraud

Compiling ROOT from source like you did is the best way to customize ROOT, but then you have the responsibility to manage that ROOT installation. If you have not installed ROOT in system directories such as /usr/local after compilation (you can check where your ROOT installation resides with which root, for example), then upgrading should be a matter of removing your current installation (e.g. removing the build/install directory) and compiling again. If you did install ROOT in system directories, you have to manually remove it from there.

As for rebuilding only cling, the simplest hack might be this:

1. Backup install and build directories of ROOT.
2. Remove contents of install directory.
3. cd to your build directory and remove interpreter/cling directory here.
4. Run cmake command with your appropriate flags.
5. Run build and install commands.

This is not guaranteed to work. There were more elaborated instruction:

Remove cling warning

Solution: (Ubuntu) Remove all folders and files in your Ubuntu with llvm, clang, cling and Cmake in the name. Re-install Cmake. sudo apt-get install cmake Go to this site: https://raw.githubusercontent.com/karies/cling-all-in-one/master/clone.sh and execute the script in your Ubuntu. Cling will work fine again. For avoid problems, you can update Cmake before execute the script. Cheers, Usori.

To sum up, I suggest that instead of investing time into exploring how to rebuild only cling, you could, with more reliable results, just rebuild from scratch (may be with a newer version of ROOT to justify time investment) or install from a pre-compiled binaries available for Ubuntu.

Alternatively, you can simply downgrade gcc, delaying the upgrade of both ROOT and gcc.