[lammps-users] Segmentation fault when using compute group/group and hybrid pair style

Dear all,

I’m trying to run a simulation using the hybrid pair style using AIREBO and an LJ + Coulomb potential.
I’m using the latest LAMMPS version (29 Oct 2020) compiled with the options:
-DPKG_MANYBODY=yes
-DPKG_GRANULAR=yes
-DPKG_MOLECULE=yes
-DPKG_KSPACE=yes
-DPKG_RIGID=yes
-DPKG_MC=yes
-DPKG_USER-REAXC=yes \

When I run the attached input with the “compute group/group” line commented, LAMMPS runs just fine.

However, if I uncomment that line I get a segfault.

Am I missing something? I looked into the documentation of both hybrid pair style and compute group/group but did not see any warnings concerning the compatibility of both.

With this same compilation, I can use compute group/group with just lj/cut/coul/long just fine.

Best,

Henrique

segfault.tar.xz (48.3 KB)

This is a complex and unusual configuration. You can see that LAMMPS is creating 5 neighbor list requests to process it.
So it is quite possible that you are running into a bug.
But figuring something like that out requires the hand of the “Grand Master of ye olde neighbor list code” (cc’d).

Axel.

If you don’t get a response within a few days, please consider submitting an issue with your reproducer example attached to the LAMMPS project issue tracker on github.
https://github.com/lammps/lammps/issues

mailing list emails have a tendency to drop from people’s radar after a while (and the mailing list has a bit of traffic, too). github issues persist until they are explicitly closed.
mind you that doesn’t include any promises to resolve this in a timely fashion. we do what we can in the amount of time available, but there is just too much to do and too little time and too few people. :frowning:

thanks,
axel.

Dear Axel,

Thank you for your reply.

I hope Steve can give some input, but in the meantime, I’ll create an issue anyways, so it’s easier for you to track the bug down.

Don’t worry, I know maintaining a code as complex as LAMMPS is not an easy task. I maintain some software too (although MUCH smaller), and I know how hard it is too keep track of everything and manage our times.

Btw, thank you for doing such a great job with LAMMPS!

Best,

Henrique

You probably know this already, but the bug has been fixed. Should be in the latest patch release (tarball) or GitHub version.
Thanks for reporting it.

Steve