diff --git a/glsl_lexer.lpp b/glsl_lexer.lpp
index 06214a8eccf..34ca229de8d 100644
--- a/glsl_lexer.lpp
+++ b/glsl_lexer.lpp
@@ -37,6 +37,7 @@
 %}
 
 %option bison-bridge bison-locations reentrant noyywrap
+%option nounput noyy_top_state
 %option never-interactive
 %option prefix="_mesa_glsl_"
 %option extra-type="struct _mesa_glsl_parse_state *"