diff --git a/src/regex/regexM8.xml b/src/regex/regexM8.xml
index 3fbb440d48..630ef5a328 100644
--- a/src/regex/regexM8.xml
+++ b/src/regex/regexM8.xml
@@ -1785,7 +1785,7 @@
                 <SETTING><NAME>MWFrontEnd_C_onlystdkeywords</NAME><VALUE>0</VALUE></SETTING>
                 <SETTING><NAME>MWFrontEnd_C_enumsalwaysint</NAME><VALUE>0</VALUE></SETTING>
                 <SETTING><NAME>MWFrontEnd_C_mpwpointerstyle</NAME><VALUE>0</VALUE></SETTING>
-                <SETTING><NAME>MWFrontEnd_C_prefixname</NAME><VALUE></VALUE></SETTING>
+                <SETTING><NAME>MWFrontEnd_C_prefixname</NAME><VALUE>wx/wx_cwc.h</VALUE></SETTING>
                 <SETTING><NAME>MWFrontEnd_C_ansistrict</NAME><VALUE>0</VALUE></SETTING>
                 <SETTING><NAME>MWFrontEnd_C_mpwcnewline</NAME><VALUE>0</VALUE></SETTING>
                 <SETTING><NAME>MWFrontEnd_C_wchar_type</NAME><VALUE>1</VALUE></SETTING>