yywarn
extern void yywarn(const char *, ...);
yywarn("format conversion #%u has more than "
yywarn("format conversion #%u has more than "
yywarn("format conversion #%u uses unsupported "
yywarn("format conversion #%u cannot be combined "
yywarn("format conversion #%u name expected before "
yywarn("format conversion #%u is undefined: %%%s\n",