Path: utzoo!attcan!uunet!mailrus!cs.utexas.edu!wuarchive!udel!wack
From: wack@udel.edu (Andrew Wack)
Newsgroups: comp.sys.apple
Subject: Re: ORCA/C problems
Message-ID: <10463@nigel.udel.EDU>
Date: 8 Feb 90 00:26:43 GMT
References: <1990Feb7.034310.5315@ux1.cso.uiuc.edu>
Sender: usenet@udel.EDU
Reply-To: wack@udel.edu (Andrew Wack)
Organization: University of Delaware
Lines: 47

Speaking of ORCA/C bugs, I've got one....(actually 2).  Try the following
program:

#pragma optimize 1
#include <stdio.h>

void main(void)
{
long int x;

x = 1600;
printf("%li \n", x);
x -= 4096;
printf("%li \n", x);
}

What you should get is 1600 and -2496, instead it generates 1600 and 
2^17 - 4096 + 1600 (I forget what it is, but I know how the compiler
is comming up with it).  If you remove the optimize pragma it works
fine.  Also it doesn't help to type-cast the 4096 as (long) (and you
shouldn't have to).  I suspect that when the optimizer is doing its
constant expression evaluation, it generates code to subtract 4096 as
though it were an int, not a long, which would result in the funny
answer.

The reason I say this is two bugs is that I only discovered this one
because the compiler has been giving me the "terminal compiler error" for
a piece of code I've been working on
and sending me back to the text edditor when I compile with no optimiation.
If I turn on optimize 1, the terminal error goes away, but I get the above
funny results.

Actualy I just thought of a third minor bug in the assembly language 
displays...the dissasembler dissasembles a TCS as a TSC (or vice-versa,
I can't remember right now).  This creates a problem when doing debugging
on the desktop at the assembly level, since their emulator follows this 
error!  Makes it kind of tough to save the stack pointer.

Does anybody know if these bugs (primarily the first two) are fixed in the
beta compiler?  I'm really getting tired of wasting time coding around 
these problems.  (Although I must say I'm very impressed by the Desktop and
ORCA/C in general for a version 1.0 product).

--
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Andrew Wack                               Gravitation cannot be held responsible
ARPA : wack@udel.edu               for people falling in love -- Albert Einstein