attempted linux build fix

I am so confused

CMakeLists.txt

@@ -68,6 +68,6 @@ set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3")
 if (CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -stdlib=libc++ -lc++abi")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -fsanitize=undefined")
+    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -stdlib=libc++ -fsanitize=undefined")
     set(PROJECT_WARNINGS ${CLANG_WARNINGS})
 endif ()