diff --git a/compiler/cpp/src/thriftl.ll b/compiler/cpp/src/thriftl.ll
index b8c36c3..17ac818 100644
--- a/compiler/cpp/src/thriftl.ll
+++ b/compiler/cpp/src/thriftl.ll
@@ -61,6 +61,11 @@
 %option noyywrap
 
 /**
+ * We don't use it, and it fires up warnings at -Wall
+ */
+%option nounput
+
+/**
  * Helper definitions, comments, constants, and whatnot
  */