diff --git a/indra/cmake/00-Common.cmake b/indra/cmake/00-Common.cmake
index 339e1adfbd6d72c7755a77419c1b9be8560db919..aa0cd8d255bd0badd9bef5d908cb287ba11fb335 100644
--- a/indra/cmake/00-Common.cmake
+++ b/indra/cmake/00-Common.cmake
@@ -191,6 +191,7 @@ if (WINDOWS)
       /D_WINSOCK_DEPRECATED_NO_WARNINGS
       /DBOOST_CONFIG_SUPPRESS_OUTDATED_MESSAGE
       /DBOOST_ALLOW_DEPRECATED_HEADERS
+      /D_SILENCE_CXX20_CISO646_REMOVED_WARNING
       )
 
   # library linkage defines