diff -Nrup a/src/flex.skl b/src/flex.skl
--- a/src/flex.skl	2015-11-10 18:28:54.000000000 -0500
+++ b/src/flex.skl	2016-03-07 23:52:46.527139783 -0500
@@ -506,7 +506,7 @@ m4_ifdef( [[M4_YY_NOT_IN_HEADER]],
      */
     #define  YY_LESS_LINENO(n) \
             do { \
-                int yyl;\
+                yy_size_t yyl;\
                 for ( yyl = n; yyl < yyleng; ++yyl )\
                     if ( yytext[yyl] == '\n' )\
                         --yylineno;\
@@ -532,7 +532,7 @@ m4_ifdef( [[M4_YY_NOT_IN_HEADER]],
 	do \
 		{ \
 		/* Undo effects of setting up yytext. */ \
-        int yyless_macro_arg = (n); \
+        yy_size_t yyless_macro_arg = (n); \
         YY_LESS_LINENO(yyless_macro_arg);\
 		*yy_cp = YY_G(yy_hold_char); \
 		YY_RESTORE_YY_MORE_OFFSET \
@@ -2591,7 +2591,7 @@ void yyFlexLexer::LexerError( yyconst ch
 	do \
 		{ \
 		/* Undo effects of setting up yytext. */ \
-        int yyless_macro_arg = (n); \
+        yy_size_t yyless_macro_arg = (n); \
         YY_LESS_LINENO(yyless_macro_arg);\
 		yytext[yyleng] = YY_G(yy_hold_char); \
 		YY_G(yy_c_buf_p) = yytext + yyless_macro_arg; \