dnl 2.5.36-37 that cause signed/unsigned mismatch,
dnl http://sourceforge.net/p/flex/bugs/140/
AS_IF([test "$LEX" = flex],
[AS_CASE([`$LEX -V`],
dnl 2.5.36-37 that cause signed/unsigned mismatch,
dnl http://sourceforge.net/p/flex/bugs/140/
AS_IF([test "$LEX" = flex],
[AS_CASE([`$LEX -V`],