diff --git a/src/perl/ui/Themes.xs b/src/perl/ui/Themes.xs
index 8aa30410..4afd437c 100644
--- a/src/perl/ui/Themes.xs
+++ b/src/perl/ui/Themes.xs
@@ -137,7 +137,8 @@ CODE:
         printformat_perl(&dest, format, arglist);
 
 void
-abstracts_register(SV *abstracts)
+abstracts_register(abstracts)
+	SV *abstracts
 PREINIT:
 	AV *av;
 	char *key, *value;