diff --git a/dtc-lexer.l b/dtc-lexer.l
index 1a16cae..0f94dfc 100644
--- a/dtc-lexer.l
+++ b/dtc-lexer.l
@@ -18,7 +18,7 @@
  *                                                                   USA 
  */
 
-%option noyywrap
+%option noyywrap nounput
 
 %x CELLDATA
 %x BYTESTRING