diff --git a/third_party/CLI/CLI11.hpp b/third_party/CLI/CLI11.hpp
index 33e937b87f3..2b426c5de72 100644
--- a/third_party/CLI/CLI11.hpp
+++ b/third_party/CLI/CLI11.hpp
@@ -158,7 +158,7 @@
 #endif
 
 /** <codecvt> availability */
-#if defined(__APPLE__) && defined(__clang__)
+#if defined(__clang__)
 #define CLI11_HAS_CODECVT 0
 #elif defined(__GNUC__) && !defined(__llvm__) && !defined(__INTEL_COMPILER) && __GNUC__ < 5
 #define CLI11_HAS_CODECVT 0
diff --git a/third_party/CMakeLists.txt b/third_party/CMakeLists.txt
index a31d24971e9..766f193cb51 100644
--- a/third_party/CMakeLists.txt
+++ b/third_party/CMakeLists.txt
@@ -134,11 +134,15 @@ if(BUILD_TESTING)
   set_target_properties(gtest_main PROPERTIES FOLDER ThirdParty/gtest)
   set_target_properties(gmock PROPERTIES FOLDER ThirdParty/gtest)
   set_target_properties(gmock_main PROPERTIES FOLDER ThirdParty/gtest)
+
+  set(is_clang "$<CXX_COMPILER_ID:Clang>")
+  set(v21_or_later "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,21>")
+  set(is_clang_v21_or_later "$<AND:${is_clang},${v21_or_later}>")
   foreach(_gtest_target gtest gtest_main gmock gmock_main)
     if(TARGET ${_gtest_target})
       target_compile_options(${_gtest_target}
         PRIVATE
-          $<$<COMPILE_LANG_AND_ID:CXX,Clang>:-Wno-character-conversion>
+          "$<${is_clang_v21_or_later}:-Wno-character-conversion>"
           $<$<COMPILE_LANG_AND_ID:CXX,Clang,AppleClang>:-Wno-deprecated-declarations>
       )
     endif()