Xref: utzoo comp.software-eng:2651 comp.misc:7628
Path: utzoo!attcan!uunet!wuarchive!usc!ucsd!ucbvax!unisoft!hoptoad!tim
From: tim@hoptoad.uucp (Tim Maroney)
Newsgroups: comp.software-eng,comp.misc
Subject: Re: Linkers
Message-ID: <9232@hoptoad.uucp>
Date: 9 Dec 89 05:23:01 GMT
References: <9185@hoptoad.uucp> <530@enea.se>
Reply-To: tim@hoptoad.UUCP (Tim Maroney)
Organization: Eclectic Software, San Francisco
Lines: 33

In article <530@enea.se> sommar@enea.se (Erland Sommarskog) writes:
>Tim Maroney (tim@hoptoad.UUCP) writes:
>>WHAT?  What year is this?  I don't think I've ever used a linker that
>>didn't eliminate unused routines.  Any such linker would be seriously
>>brain damaged.
>
>While this may seem credible at first glance, it is at not second.

Try the third....

>I am very happy that the linker we use in our project (VMS LINK)
>don't remove uncalled routines. In that case it would notice that
>this routine is never called, and never is this one and so forth and
>rapidly it would have removed the 250 top modules.
>
>The trick is in Cobol where you can say
>   Routine PIC x(32).
>   ...
>   CALL Routine USING....
>Routine is not a literal, it is a string variable. All top entries
>corresponds to menu choices. When the user enters a menu choice,
>it is looked up in a database, which gives you the name of the
>procedure to call.

And of course, all such routines are referenced; pointers to them are
stored in this database.  The analogue in C is when a routine is never
explicitly called, but a function pointer to it is used in a referenced
routine.  The routine is referenced, just as routines entered into a
late-binding database are referenced.
-- 
Tim Maroney, Mac Software Consultant, sun!hoptoad!tim, tim@toad.com

"This signature is not to be quoted." -- Erland Sommarskog