call to revolt

[Blair P. Houghton]

In article <1991Jun25.181916.26586 at zoo.toronto.edu> henry at zoo.toronto.edu (Henry Spencer) writes:
>In article <rabson.677868220 at physics.ubc.ca> rabson at physics.ubc.ca (David Rabson) writes:
>>Outlawing lvalue casts, however, borders on fascism.
>>		void *thing;
>>		((int *)thing)++;

And then I suppose the next line is

		((double *)thing)++;

>Remember that `void *' and `int *' need not even be the
>same size, much less have the same representation.  A cast
>is a conversion operation, not a "view these bits
>differently" operation.  (See K&R1 page 42.)

Much less the same location; after the cast the value may be
sitting in an accumulator, or in the phase space on the
wiring at 14.5 picoseconds antecedent to the accumulator
(Cray was a genius, kids, not just another hacker :-)),
but not necessarily anywhere near the storage for `thing'.

>Please cite K&R chapter and verse for thinking that casts are lvalues.

They certainly aren't addressable.

>>The rest of us should stop sitting back and start fighting.  If enough
>>customers insist on casting lvalues and otherwising ignoring ansi's

They'll be left behind.

I've seen other standards that have had _real_ problems in
them, and nobody bothers with them any more.  ANSI X3.159-1989,
on the other hand, is pretty solid, almost impervious.

				--Blair
				  "Write when you find a bug."