diff --git a/devel/ispc/Makefile b/devel/ispc/Makefile
index 8ed00522aaf9..05624cbf9db3 100644
--- a/devel/ispc/Makefile
+++ b/devel/ispc/Makefile
@@ -1,81 +1,81 @@
 # Created by: Yuri Victorovich <yuri@rawbw.com>
 
 PORTNAME=	ispc
 DISTVERSIONPREFIX=	v
 DISTVERSION=	1.16.1
 PORTREVISION=	3
 CATEGORIES=	devel
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Intel's compiler for high-performance SIMD programming
 
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 
 ONLY_FOR_ARCHS=		aarch64 amd64 i386
 ONLY_FOR_ARCHS_REASON=	only available for these architectures
 
 BUILD_DEPENDS=	${LOCALBASE}/bin/flex:textproc/flex \
 		m4:devel/m4
 LIB_DEPENDS=	libLLVM.so:devel/llvm${LLVM_VERSION}
 
 USES=		bison cmake compiler:c++14-lang python:build,test shebangfix
 USE_GITHUB=	yes
 SHEBANG_FILES=	*.py
 
 CONFIGURE_ENV=	PATH=${LOCALBASE}/llvm${LLVM_VERSION}/bin:${PATH}
 CMAKE_OFF=	ISPC_NO_DUMPS ISPC_INCLUDE_EXAMPLES
 
 BINARY_ALIAS=	flex=${LOCALBASE}/bin/flex python=${PYTHON_CMD} m4=${LOCALBASE}/bin/gm4
 
 PLIST_FILES=	bin/ispc \
 		bin/check_isa
 
 OPTIONS_DEFINE_amd64=	GENX
 OPTIONS_DEFAULT_amd64=	GENX
 
 GENX_DESC=		Intel GPU 8/16-wide SIMD support
 GENX_BUILD_DEPENDS=	${LOCALBASE}/llvm${LLVM_VERSION}/lib/libLLVMGenXIntrinsics.a:devel/vc-intrinsics@llvm${LLVM_VERSION}
 GENX_LIB_DEPENDS=	libze_loader.so:devel/level-zero \
 			libLLVMSPIRVLib.so.${LLVM_VERSION}:devel/spirv-llvm-translator@llvm${LLVM_VERSION}
 GENX_CMAKE_BOOL=	GENX_ENABLED
 GENX_CMAKE_BOOL_OFF=	ISPCRT_BUILD_TESTS
 GENX_CMAKE_ON=		-DGENX_DEPS_DIR:PATH="${LOCALBASE}/llvm${LLVM_VERSION}"
 GENX_PLIST_FILES=	include/ispcrt/ispcrt.h \
 			include/ispcrt/ispcrt.hpp \
 			include/ispcrt/ispcrt.isph \
 			lib/cmake/ispcrt-${PORTVERSION}/Findlevel_zero.cmake \
 			lib/cmake/ispcrt-${PORTVERSION}/ispc.cmake \
 			lib/cmake/ispcrt-${PORTVERSION}/ispcrtConfig.cmake \
 			lib/cmake/ispcrt-${PORTVERSION}/ispcrt_Exports-%%CMAKE_BUILD_TYPE%%.cmake \
 			lib/cmake/ispcrt-${PORTVERSION}/ispcrt_Exports.cmake \
 			lib/libispcrt.so \
 			lib/libispcrt.so.1 \
 			lib/libispcrt.so.${PORTVERSION} \
 			lib/libispcrt_static.a
 
 #.include <bsd.port.options.mk>
 #.if ${LLVM_DEFAULT:M[7891]0} || ${LLVM_DEFAULT:M1[12]} # max(LLVM_DEFAULT,13)
 #LLVM_VERSION=	13
 #.else
 #LLVM_VERSION=	${LLVM_DEFAULT}
 #.endif
 
-LLVM_VERSION=	11 # 13 fails on some systems with: Assertion failed: (PointeeType && "Must specify element type"), function Create
+LLVM_VERSION?=	11 # 13 fails on some systems with: Assertion failed: (PointeeType && "Must specify element type"), function Create
 
 do-test: # some tests fail: https://github.com/ispc/ispc/issues/1868
 	@cd ${WRKSRC} && ISPC_HOME=${BUILD_WRKSRC}/bin ./run_tests.py
 
 test-check-all: # the upstream claims that some of these checks are broken without using their patched llvm version, hence using llvm-devel
 	@cd ${BUILD_WRKSRC} && ${SETENV} ${MAKE_ENV} ${MAKE_CMD} ${MAKE_ARGS} check-all
 
 run-examples: build
 	@[ -f ${LOCALBASE}/lib/libtbb.so ] || ! echo "ERROR run-examples target requires devel/tbb package installed"
 .for e in simple sort mandelbrot stencil
 	@cd ${WRKSRC}/examples/${e} && \
 	${ECHO} "===> Running example ${e}" && \
 	${SETENV} ${MAKE_ENV} ${MAKE_CMD} ${MAKE_ARGS} && \
 	./${e}
 .endfor
 
 .include <bsd.port.mk>