diff --git a/docs/tools/clang.pod b/docs/tools/clang.pod
index b99eb8f..9f7a448 100644
--- a/docs/tools/clang.pod
+++ b/docs/tools/clang.pod
@@ -175,6 +175,10 @@
 
 Enable support for Microsoft extensions.
 
+=item B<-fmsc-version=>
+
+Set _MSC_VER. Defaults to 1300 on Windows. Not set otherwise.
+
 =item B<-fborland-extensions>
 
 Enable support for Borland extensions.