Subject: Re: Assming char == signed char?
To: None <christos@deshaw.com>
From: Charles M. Hannum <mycroft@ai.mit.edu>
List: tech-ports
Date: 07/02/1995 00:50:42 
   >As an aside is the correct fix:
   >
   >		(signed char)tty->a_member_of_type_char == -1

   This is not a desirable fix, because it assumes that one has access to
   an ansi compiler.

Actually, it specifically assumes you have GCC.  In ANSI C, a casted
lvalue is not required to be a lvalue, and with some compilers it is
not.