Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: effect of free()
Message-ID: <11109@smoke.BRL.MIL>
Date: 19 Sep 89 20:56:50 GMT
References: <319@cubmol.BIO.COLUMBIA.EDU> <3756@buengc.BU.EDU> <10988@smoke.BRL.MIL> <9339@attctc.Dallas.TX.US> <1641@levels.sait.edu.au> <11070@smoke.BRL.MIL> <1693@levels.sait.edu.au>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 20

In article <1693@levels.sait.edu.au> CCDN@levels.sait.edu.au (DAVID NEWALL) writes:
-In article <11070@smoke.BRL.MIL>, gwyn@smoke.BRL.MIL (Doug Gwyn) writes:
-> In particular, there is a school of thought that says machine architecture
-> should be designed to assist in program reliability.  That school
-> occasionally influences computer architectures such that actions like
-> merely continuing to shuffle around invalid pointers cause an error trap
-> to be taken.
-That is supposed to make programs reliable?

Not in itself; it's a side effect of the architecture design.

-Testing parameters for "correctness", rather than blindly hoping that they
-are "correct", is one way to make programs more reliable.  Does that school
-of yours suggest that it's OK to believe all (non-null) pointers?

It's not "my school"; I'm just telling you about it.  There is far more
to this than error traps on invalid pointer reference.  If you have a
reasonable textbook on computer architectures, try looking there.
Otherwise Glen Myer's "Advances in Computer Architecture" would be a
good starting point for enlightenment.