Path: utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!tikal!hplsla!hpubvwa!mimsy!chris
From: chris@mimsy
Newsgroups: comp.lang.c
Subject: pointer arithmatic error messages
Message-ID: <9979@mimsy>
Date: 30 Dec 87 13:18:00 GMT
Lines: 29

In article <3899@uw-june.UUCP>, pardo@uw-june.UUCP (David Keppel) writes:
>typedef int foo;
[...]
>    foo		*a, *b, *c;
>    a = b + c;
>    b += c
>    if ((c += a) != b)
>	a = b;
>
>Pcc complains about *every* operator excpet the last "=" (yes, even "!=").

It complains about the `!=' because you confused with with the `+=' (it
lost the type of c).

>I would like to know:
>    why?

Because it is meaningless to add two pointers.

>    how can I make it work?  (yes, I really want to do "b+=c")

What do you expect to happen?

>    how can I make it work without doing "((int) b) += (int) c"?

That depends on what you want done.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris