diff --git a/src/proto/search.pro b/src/proto/search.pro
index 339aa34..3b9ca5c 100644
--- a/src/proto/search.pro
+++ b/src/proto/search.pro
@@ -7,6 +7,7 @@
 void restore_search_patterns(void);
 void free_search_patterns(void);
 int ignorecase(char_u *pat);
+int ignorecase_opt(char_u *pat, int ic_in, int scs);
 int pat_has_uppercase(char_u *pat);
 char_u *last_csearch(void);
 int last_csearch_forward(void);