diff --git a/src/mesa/drivers/dri/i965/brw_disasm.c b/src/mesa/drivers/dri/i965/brw_disasm.c
index 863a6b323ce..c92c534cc12 100644
--- a/src/mesa/drivers/dri/i965/brw_disasm.c
+++ b/src/mesa/drivers/dri/i965/brw_disasm.c
@@ -596,6 +596,9 @@ string(FILE *file, const char *string)
    return 0;
 }
 
+static int
+format(FILE *f, const char *format, ...) PRINTFLIKE(2, 3);
+
 static int
 format(FILE *f, const char *format, ...)
 {