diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt
--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@@ -160,10 +160,10 @@
 if (LIBUNWIND_ENABLE_CET)
   add_compile_flags_if_supported(-fcf-protection=full)
   add_compile_flags_if_supported(-mshstk)
-  if (NOT LIBUNWIND_SUPPORTS_FCF_PROTECTION_EQ_FULL_FLAG)
+  if (NOT CXX_SUPPORTS_FCF_PROTECTION_EQ_FULL_FLAG)
     message(SEND_ERROR "Compiler doesn't support CET -fcf-protection option!")
   endif()
-  if (NOT LIBUNWIND_SUPPORTS_MSHSTK_FLAG)
+  if (NOT CXX_SUPPORTS_MSHSTK_FLAG)
     message(SEND_ERROR "Compiler doesn't support CET -mshstk option!")
   endif()
 endif()