Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!tcdcs!swift.cs.tcd.ie!maths.tcd.ie!jorice
From: jorice@maths.tcd.ie (Jonathan Rice)
Newsgroups: comp.windows.x
Subject: Re: Can't fine XtInherit
Message-ID: <1990Jun27.165544.4413@maths.tcd.ie>
Date: 27 Jun 90 16:55:44 GMT
References: <7557@ccncsu.ColoState.EDU>
Organization: Dept. of Maths, Trinity College, Dublin, Ireland.
Lines: 45

In <7557@ccncsu.ColoState.EDU> thorson@typhoon.atmos.colostate.edu (Bill Thorson) writes:

>I am trying to build Metafont with the X11 interface.  The problem I
>am running into is that it is looking for XtInherit and can't find
>it.  Can anyone tell me what library that can be found in?

I've had a similar but possibly unrelated problem. First of all, by "XtInherit"
I take it that you mean the _XtInherit procedure, which is used as the test
value to determine if a widget class inherits a widget field value from its
superclass or not. This is described on Page 21 of the X11R4 X Toolkit
Intrinsics manual. The procedure is defined in mit/lib/Xt/Initialize.c and is
eventually built into the Xt library libXt.a.

Now to my problem, which has to do with the _XtInherit beastie and SunOS shared
libraries. I'm using SunOS 4.0.3 on a Sparcstation1 and gcc 1.36. I'm running
X11R4 and using the Athena widget set, both of which were compiled using cc.
SYMPTOM: At run-time, ld.so complains
		ld.so: Undefined symbol: __XtInherit
	If I use static libXt.a, no problems. Links fine.

Now, from a cursory inspection of the X source, it seems that this is to do with
some tricking around with names so that _XtInherit has a consistent value
throughout all shared copies. _XtInherit is one of several routines which have
static stub versions defined for them in mit/lib/Xt/sharedlib.c. When using the
value of _XtInherit, you therefore get this single static value. When *calling*
_XtInherit, however, the stub routine in turn calls the original (now shared)
version which has been renamed to __XtInherit by a #define, which carries out
the original error-printing function. That's the way it *should* work, as far
as I can see. So why can't ld.so find the shared version? Here's what I get
when I run nm on shared and static versions of Xt to see what's actually there:
	libXt.a:Initialize.o:0000002c T __XtInherit
	libXt.sa.4.0:sharedlib.o:00000000 T __XtInherit
	libXt.sa.4.0:sharedlib.o:         U ___XtInherit
	libXt.so.4.0:0000c19c T ___XtInherit
That *looks* correct to me. 
			Any suggestions?

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|     Jonathan Rice      | Email: jorice@cs.tcd.ie | He was a common fly       |
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