In some email I received from Jaromír Dolecek, sie wrote:
> 
> Darren Reed wrote:
> > Compiling up some lex/yacc code, I get this:
> > 
> > cc1: warnings being treated as errors
> > lex.yy.c:1121: warning: `yyunput' defined but not used
> > *** Error code 1
> > 
> > *nowhere* is this function used or called (by my code).
> > 
> > I have other lex/yacc files which compile cleanly.  I'm
> > at a loss to explain the difference.
> > 
> > Clues, anyone ?
> 
> It seems you need to
> #define YY_NO_INPUT
> 
> in your lex source.

So why does it work, some of the time, without that #define there ?

Darren