Created attachment 208201 [details]
Upstream PR: https://github.com/lammps/lammps/pull/1483
Don't set BUILD_OMP. libomp is correctly found and used when building with clang anyway.
Now see D21994.
A commit references this bug:
Date: Thu Nov 28 14:20:18 UTC 2019
New revision: 518579
science/lammps: fix build on GCC architectures
Don't enable OpenMP everywhere, it causes an error with GCC, reported on https://github.com/lammps/lammps/pull/1483
This requires some hackery with ports not supporting options for specific compilers.
OPENMP flag has removed option helpers due to them not being respected otherwise.
Approved by: yuri (maintainer, earlier versior), tcberner (mentor, earlier version)
Differential Revision: https://reviews.freebsd.org/D21994