diff --git a/src/proto/syntax.pro b/src/proto/syntax.pro
index aae187f..a505ee7 100644
--- a/src/proto/syntax.pro
+++ b/src/proto/syntax.pro
@@ -1,5 +1,5 @@
 /* syntax.c */
-void syntax_start(win_T *wp, linenr_T lnum);
+void syntax_start(win_T *wp, linenr_T lnum, proftime_T *syntax_tm);
 void syn_stack_free_all(synblock_T *block);
 void syn_stack_apply_changes(buf_T *buf);
 void syntax_end_parsing(linenr_T lnum);