Support #25501

Request to provide LArSoft builds for ubuntu LTS 20

Added by Tracy Usher 2 months ago. Updated 2 months ago.

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I've moved to ubuntu 20.04 LTS and would like to request the LArSoft folks to provide builds for this operating system.
I believe this should be straightforward... I had actually updated my kernel to 5.4 when I was running ubuntu 18 and did not encounter problems building because of this. I'm now building LArSoft in VirtualBox with ubuntu 18.05 and just discovered it also is using kernel 5.4 and this is what I have for ubuntu 20.04. I am not able to build on ubuntu 20.04 with the standard scripts (starting with buildFW) because they don't recognize "u20"... so if someone can tell me how to make modifications for that I'm willing to give it a try...
Thanks very much!


#1 Updated by Lynn Garren 2 months ago

Tracy, thank you for the request. We will need to make adjustments on this end for LTS 20. It's not, unfortunately, as simple as telling you what to change.

#2 Updated by Lynn Garren 2 months ago

Also, it should be noted that I am finding and fixing problems with the u18 build. That is a necessary first step.

#3 Updated by Lynn Garren 2 months ago

python3 is installed by default, but there is no /usr/bin/python. The correct way to provide /usr/bin/python is the following. After running this command "python -V" returns Python 3.8.5

sudo apt install python-is-python3

#4 Updated by Lynn Garren 2 months ago

At this point I have a successful prof build of larsoft v09_16_00 on Ubuntu LTS 20 - with gcc 9.3 (e20).

The build of gcc 8.2 (e19) failed. The failure has not been investigated.

There is a problem with the e20 debug build of larsoft. That is not limited to Ubuntu will be fixed in the next release.

Some fixes have been made in the build cfg files, but no changes were made to buildFW. Do, however, make sure you have the latest buildFW from SciSoft.

I was unable to build castxml, libtorch, or the current trtis_clients release.

#5 Updated by Kyle Knoepfel 2 months ago

  • Status changed from New to Accepted

#6 Updated by Lynn Garren 2 months ago

We note that the native compiler on LTS 20 is gcc 9.3.0. This means that we can support e20 builds, but not e19 or c7 builds.

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