Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uunet!mcsun!cernvax!ethz!forty2!mecazh!paul
From: paul@mecazh.UUCP (Paul Breslaw)
Newsgroups: comp.sys.hp
Subject: Re: Possible HP-UX compiler optimizer bug (found while making Perl)
Message-ID: <368@node17.mecazh.UUCP>
Date: 13 Nov 89 16:34:10 GMT
References: <4413@fmeed1.UUCP>
Organization: Mecasoft SA, Zurich, Switzerland
Lines: 42

wehr@fmeed1.UUCP (Bruce Wehr) writes:

> We just got Perl 3.0 from c.s.u.  Making it on our HP 9000/370 running
> HP-UX 6.5 with the optimizer caused the compiler to hang on these files:
> eval.c (&& teval.c), toke.c (&& ttoke.c), x2p/walk.c.  These files had
> to be manually compiled without the optimizer (we told Configure to use
> -O).

> Has anyone else experienced this, or should I start looking for
> something I did wrong?  Any help would be appreciated.

I think the easiest advice is NEVER EVER to compile PD software (or
anything that you do not know initimately) with the HP pessimiser.

For example, the following programs will run correctly under HP-UX6.5
when compiled without the -O switch, and will break here and there with
the -O switch:-

    xdvi
    thack
    gnu emacs 18.52
    perl 3.0

I am not interested in people offering advice about:-

  "module foo.c being the culprit, and the rest of the program 
   compiles nicely with -O, oh as long as it is not the first Friday 
   of the month, and there are no black cats on the way to work"

Either an optimiser works correctly as often as the rest of the compiler, 
or you can forget about it. There is nothing worse than trying to debug
a program whose bugs disappear with the -g switch (== ~-O).


Paul Breslaw


-- 
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Paul Breslaw, Mecasoft SA,          |  telephone :  41 1 362 2040
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