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From: idall@augean.OZ (Ian Dall)
Newsgroups: comp.lang.c
Subject: Re: effect of free()
Message-ID: <591@augean.OZ>
Date: 20 Sep 89 07:12:04 GMT
References: <319@cubmol.BIO.COLUMBIA.EDU> <3756@buengc.BU.EDU> <1989Aug17.005548.745@twwells.com> <16022@vail.ICO.ISC.COM> <248@seti.inria.fr> <246@ssp1.idca.tds.philips.nl> <21952@cup.portal.com> <10983@smoke.BRL.MIL>
Organization: Engineering Faculty, University of Adelaide, Australia
Lines: 28
Reply-To:

In article <10983@smoke.BRL.MIL> gwyn@brl.arpa (Doug Gwyn) writes:
>In article <21952@cup.portal.com> Tim_CDC_Roberts@cup.portal.com writes:
>>Isn't this a quality of implementation issue?  ...  Thus, in the case above,
>>I would insist that the compiler writer move the address to a general-purpose
>>register and do the comparison there.
>
>It runs contrary to the "spirit of C" to require the implementation to
>generate code that does operations the hard way when a more natural way
>would suffice.

It violates the law of least surprises to have variables suddenly made
inaccessable by being a call by value argument to a function.

C used to be a language where I felt comfortable because I had a pretty
good idea of its basic principles. The concept of variables becoming
invalidated by function calls seems to my very counter-intuitive and
unless there is a STRONG efficiency argument on a reasonably desirable
architecture, then I think compilers should be required to do the comparison
in such a way that they don't generate traps.

.
.
.

-- 
 Ian Dall           life (n). A sexually transmitted disease which afflicts
                              some people more severely than others.
idall@augean.oz