Index: lib/antlr4-cpp-runtime/CMakeLists.txt
--- lib/antlr4-cpp-runtime/CMakeLists.txt.orig
+++ lib/antlr4-cpp-runtime/CMakeLists.txt
@@ -95,7 +95,7 @@ elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND ANDR
 	# and without -stdlib=libc++ cxxflags
 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND APPLE)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17 -stdlib=libc++")
-elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND ( CMAKE_SYSTEM_NAME MATCHES "Linux" OR CMAKE_SYSTEM_NAME MATCHES "FreeBSD") )
+elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND ( CMAKE_SYSTEM_NAME MATCHES "Linux" OR CMAKE_SYSTEM_NAME MATCHES "FreeBSD" OR CMAKE_SYSTEM_NAME MATCHES "OpenBSD") )
     execute_process(
         COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE CLANG_VERSION)
     if(NOT (CLANG_VERSION VERSION_GREATER 4.2.1 OR CLANG_VERSION VERSION_EQUAL 4.2.1))
