1 files changed, 1 insertions, 1 deletions

diff --git a/usr.bin/colldef/parse.y b/usr.bin/colldef/parse.y
index 5621a214f677d..a5806d1f001ca 100644
--- a/usr.bin/colldef/parse.y
+++ b/usr.bin/colldef/parse.y
@@ -39,7 +39,7 @@
 
 extern int line_no;
 extern FILE *yyin;
-void yyerror(char *fmt, ...);
+void yyerror(char *fmt, ...) __printflike(1, 2);
 int yyparse(void);
 int yylex(void);
 static void usage __P((void));