Index: head/security/klee/Makefile
===================================================================
--- head/security/klee/Makefile
+++ head/security/klee/Makefile
@@ -17,7 +17,8 @@
 RUN_DEPENDS=	llvm-config${LLVM_DEFAULT}:devel/llvm${LLVM_DEFAULT} \
 		${PYTHON_PKGNAMEPREFIX}tabulate>0:devel/py-tabulate@${PY_FLAVOR}
 
-USES=		cmake localbase pkgconfig python:3.5+,run shebangfix
+USES=		cmake compiler:c++14-lang localbase pkgconfig python:3.5+,run \
+		shebangfix
 USE_GITHUB=	yes
 SHEBANG_FILES=	tools/klee-stats/klee-stats tools/ktest-tool/ktest-tool
 USE_LDCONFIG=	yes