Index: head/science/lammps/Makefile
===================================================================
--- head/science/lammps/Makefile	(revision 518578)
+++ head/science/lammps/Makefile	(revision 518579)
@@ -1,67 +1,76 @@
 # $FreeBSD$
 
 PORTNAME=	lammps
 PORTVERSION=	${GH_TAGNAME:C/(stable|patch)_([0-9]{1,2})([A-Z][a-z][a-z])([0-9]{4})/\4.\3.\2/S/Jan/01/S/Feb/02/S/Mar/03/S/Apr/04/S/May/05/S/Jun/06/S/Jul/07/S/Aug/08/S/Sep/09/S/Oct/10/S/Nov/11/S/Dec/12/}
+PORTREVISION=	1
 CATEGORIES=	science
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Classical molecular dynamics code with a focus on materials modeling
 
 LICENSE=	GPLv2
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 BROKEN_i386=	undefined reference to `__atomic_load'
 CONFLICTS_BUILD=	ga # conflicts with include/error.h, already fixed in the head
 
 USES=		blaslapack:openblas cmake:noninja eigen:3 fortran localbase:ldflags shebangfix
 USE_GITHUB=	yes
 GH_TAGNAME=	patch_20Nov2019
 SHEBANG_GLOB=	*.sh *.bash
 SHEBANG_FILES=	lib/kokkos/bin/nvcc_wrapper
 
 CMAKE_SOURCE_PATH=	${WRKSRC}/cmake
-CMAKE_ARGS=	-DBLA_VENDOR:STRING="OpenBLAS"
+CMAKE_ARGS=	-DBLA_VENDOR:STRING="OpenBLAS" ${CMAKE_ARGS_${CHOSEN_COMPILER_TYPE}}
+CMAKE_ARGS_gcc=	-DBUILD_OMP:BOOL=false
 
 OPTIONS_DEFINE=		JPEG PNG GZIP FFMPEG VORONOI LATTE
+OPTIONS_DEFINE_clang=	OPENMP
 OPTIONS_GROUP=		PARALLEL
-OPTIONS_GROUP_PARALLEL=	MPI OPENMP
-OPTIONS_DEFAULT=	MPI OPENMP JPEG PNG GZIP FFMPEG VORONOI LATTE
+OPTIONS_GROUP_PARALLEL=	MPI ${OPTIONS_DEFINE_${CHOSEN_COMPILER_TYPE}}
+OPTIONS_DEFAULT=	MPI JPEG PNG GZIP FFMPEG VORONOI LATTE ${OPTIONS_DEFAULT_${CHOSEN_COMPILER_TYPE}}
+OPTIONS_DEFAULT_clang=	OPENMP
 PARALLEL_DESC=		Enable parallelizations:
 
 MPI_CMAKE_BOOL=		BUILD_MPI
 MPI_LIB_DEPENDS=	libmpi.so:net/openmpi
+MPI_USES=		compiler:c11
 
-OPENMP_USES=		localbase
-OPENMP_CMAKE_BOOL=	BUILD_OMP
-OPENMP_LIB_DEPENDS=	libomp.so:devel/openmp
-
 FFMPEG_BUILD_DEPENDS=	ffmpeg:multimedia/ffmpeg
 FFMPEG_RUN_DEPENDS=	ffmpeg:multimedia/ffmpeg
 
 JPEG_CMAKE_BOOL=	WITH_JPEG
 JPEG_USES=		jpeg
 
 PNG_CMAKE_BOOL=		WITH_PNG
 PNG_LIB_DEPENDS=	libpng.so:graphics/png
 
 GZIP_CMAKE_BOOL=	WITH_GZIP
 
 FFMPEG_CMAKE_BOOL=	WITH_FFMPEG
 
 VORONOI_DESC=		Use voro++, Voronoi tessellation package
 VORONOI_CMAKE_BOOL=	PKG_VORONOI
 VORONOI_LIB_DEPENDS=	libvoro++.so:science/voro++
 
 LATTE_DESC=		Use LATTE package
 LATTE_CMAKE_BOOL=	PKG_LATTE
 LATTE_LIB_DEPENDS=	liblatte.so:science/latte
 
 PORTSCOUT=	ignore # due to a special version tagging scheme that this project uses portscout fails to find new versions, watching their GitHub release page instead
+
+.include <bsd.port.options.mk>
+
+.if ${PORT_OPTIONS:MOPENMP}
+USES+=	localbase
+CMAKE_ARGS+=	-DBUILD_OMP:BOOL=true
+LIB_DEPENDS+=	libomp.so:devel/openmp
+.endif
 
 post-patch:
 	@${REINPLACE_CMD} 's|SHELL = /bin/bash|SHELL = ${LOCALBASE}/bin/bash|' ${WRKSRC}/src/Makefile
 
 post-patch-FFMPEG-off:
 	@${REINPLACE_CMD} 's|find_program(FFMPEG_EXECUTABLE|#&|' ${WRKSRC}/cmake/CMakeLists.txt
 
 .include <bsd.port.mk>