Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!uc!wo!dwm
From: dwm@wo.msc.umn.edu (Don Mears)
Newsgroups: comp.arch
Subject: Re: RISC hard to program? (was: Moto's data predicts...)
Summary: RISC alignment requirements VS CISC flexibility
Message-ID: <2174@uc.msc.umn.edu>
Date: 19 Jul 90 21:47:29 GMT
References: <WSD.90Jul14184453@unnamed.cs.brown.edu> <3241@bnr-rsc.UUCP> <37655@ucbvax.BERKELEY.EDU>
Sender: news@uc.msc.umn.edu
Reply-To: dwm@msc.edu (Don Mears)
Organization: Minnesota Supercomputer Center, Minneapolis, MN
Lines: 17

In <37655@ucbvax.BERKELEY.EDU>, jbuck@galileo.berkeley.edu (Joe Buck) writes:
>If the program, when run through lint, does not print "possible pointer
>alignment problem" except for pointer values returned by malloc, and does
>not generate any other lint messages, it will not crash when compiled on
>another architecture because of an alignment problem.

For what it's worth here are 2 programs that pass lint and run on a 68000 
based Sun-3 and abort due to alignment errors on a SPARC Sun-4:

main() { int i[2], *j = i; 
	(void) printf("%d\n", *(int *) ((int)j + 2));   }

union u { int i; int *ip} un; int ai[10];
main() { un.ip = ai; un.i++; (void)printf("%d\n", *un.ip); }

Lint never guarantees correctness.   Even still, I prefer the CPU that runs
fast over the one that hides stupidisms from me.