Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!rutgers!seismo!columbia!garfield.columbia.edu!eppstein
From: eppstein@garfield.columbia.edu (David Eppstein)
Newsgroups: net.lang.c++
Subject: C++ and sizeof
Message-ID: <3580@columbia.UUCP>
Date: Fri, 24-Oct-86 17:36:32 EDT
Article-I.D.: columbia.3580
Posted: Fri Oct 24 17:36:32 1986
Date-Received: Sat, 25-Oct-86 06:43:03 EDT
References: <6206@alice.uUCp>
Sender: nobody@columbia.UUCP
Organization: Columbia University CS Department
Lines: 16

Something I guess I didn't make clear in my original posting was that
I was more interested in the effect of expanding sizeof on the
portability of the C++ translator itself.  I.e. it has to know enough
about the machine to calculate sizeof in the first place.  A compiler
I worked on forces individual chars and the starts of char arrays to
be word-aligned; this may not be a totally bizarre requirement but
it might not have been anticipated, and surely there is worse out there.

I didn't find the examples for why sizeof must be expanded
particularly convincing; while CC has to calculate the sizes in those
cases if is to accept and translate them, I am not sure that it should
accept them in the first place.  (To recap one was an array bound
declared in one place as an explicit constant and in another as a
size; the other was using sizes as case labels.)
-- 
David Eppstein, eppstein@cs.columbia.edu, seismo!columbia!cs!eppstein