Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!widener!ukma!rex!wuarchive!usc!elroy.jpl.nasa.gov!lll-winken!sol.ctr.columbia.edu!spool.mu.edu!munnari.oz.au!yoyo.aarnet.edu.au!sirius.ucs.adelaide.edu.au!fang!agq
From: agq@fang.dsto.oz (Ashleigh Quick)
Newsgroups: comp.sys.apollo
Subject: Re: Apollo CC 5.7 Optimizer bummer
Message-ID: <1526@fang.dsto.oz>
Date: 13 May 91 18:04:01 GMT
References: <1991May8.231635.8782@emperor.scs.com> <1520@fang.dsto.oz> <51760d86.20b6d@apollo.HP.COM>
Reply-To: agq@fang (Ashleigh Quick)
Distribution: comp
Organization: Defence Science and Technology Organisation
Lines: 51


In article <51760d86.20b6d@apollo.HP.COM> rehrauer@apollo.HP.COM (Steve Rehrauer) writes:
>In article <1520@fang.dsto.oz> agq@itd1.dsto.oz (Ashley Quick) writes:
!>richd@emperor.scs.com (Richard Doherty) writes:
!>>Question: Has anyone discovered optimizer problems?
!>
!>Yes.
!>
!>I have had a program which uses DOMAIN/OS mailbox calls,
!>and have had exactly the problem you describe. These calls
!>take a pointer to some storage, and fill that spot up with stuff.
!>
!>With the optimiser on, the program (only about 50 lines long) crashes
!>with a segmentation violation. When off, works fine. I tried
!>the various different optimiser levels, and found that it broke
!>at levels 3 and above (I think... it was a year ago).
!
!>No I have not reported this to HaPollo :-)
>
>SIGH.  Please DO report such problems.  We *LOVE* APRs with 50-line
>programs that fail in simple ways. :-)  Seriously, I know many of
>you have aired complaints about response-time -- I'm just a poor
>engineer on the receiving end, and sometimes for whatever reason
>I don't always receive -- but PLEASE don't just ignore a problem.
>Your short little program may've already been fixed in the latest
>compiler, or it may have serendipitously uncovered a bug that causes
>the latest 50,000-line Fortran monster on my platter to fail.
>--
>"The goons are riding motorcycles, but WE'VE  | (Steve) rehrauer@apollo.hp.com
> got a whole big metal car! This will be like |       Hewlett-Packard
> stepping on ants..." -- Freelance Police     | Massachusetts Languages Lab

A thousand humble apologies.

As I said in my original posting, the problems I saw were under SR10.1
and I cannot remember which version of the C compiler.

I have just checked the offending programs (mbx_server.c and mbx_client.c)
under SR10.3 and C compiler 68K Rev 6.7(316).

They run fine! (But: I had to remove the fudges in mbx_client.c
which explicity redefined NULL and then included stdio which promptly
redefined it....... Perhaps the DOMAIN EXAMPLES could be revised?)

So... Sorry for leading you up the garden path! :-) It appears the
problem has been cured.


Regards
Ashleigh Quick
AGQ@dstos3.dsto.oz.au