diff --git a/linuxdoc-tools/rtf-fix/rtf2rtf.l b/linuxdoc-tools/rtf-fix/rtf2rtf.l
index 7ef9c4a..5b6f73e 100644
--- a/linuxdoc-tools/rtf-fix/rtf2rtf.l
+++ b/linuxdoc-tools/rtf-fix/rtf2rtf.l
@@ -73,9 +73,8 @@ int skipnewline = 0;
 
 extern char *yytext;
 
-#if   YY_FLEX_MAJOR_VERSION > 2 \
- ||  (YY_FLEX_MAJOR_VERSION == 2 && YY_FLEX_MINOR_VERSION > 5) \
- ||  (YY_FLEX_MAJOR_VERSION == 2 && YY_FLEX_MINOR_VERSION == 5 && YY_FLEX_SUBMINOR_VERSION > 35)
+#if (YY_FLEX_MAJOR_VERSION == 2 && YY_FLEX_MINOR_VERSION == 5 && YY_FLEX_SUBMINOR_VERSION > 35) \
+ || (YY_FLEX_MAJOR_VERSION == 2 && YY_FLEX_MINOR_VERSION == 6 && YY_FLEX_SUBMINOR_VERSION == 0)
 extern yy_size_t yyleng;
 #else
 extern int yyleng;