mirror of
git://git.savannah.gnu.org/libtool.git
synced 2024-11-27 06:09:57 +08:00
611 lines
26 KiB
Plaintext
611 lines
26 KiB
Plaintext
From nobody Wed Oct 14 16:45:01 1998
|
|
X-From-Line: ian@cygnus.com Fri Apr 17 23:33:18 1998
|
|
Return-Path: <ian@cygnus.com>
|
|
Delivered-To: gord@trick.profitpress.com
|
|
Received: (qmail 23427 invoked from network); 17 Apr 1998 23:33:17 -0000
|
|
Received: from unknown (HELO bambam.m-tech.ab.ca) (127.0.0.1)
|
|
by 127.0.0.1 with SMTP; 17 Apr 1998 23:33:17 -0000
|
|
Received: from tweedledumb.cygnus.com (gateway.m-tech.ab.ca [10.0.0.1]) by bambam.m-tech.ab.ca (8.8.5/8.6.9) with ESMTP id OAA06912 for <gord@profitpress.com>; Fri, 17 Apr 1998 14:17:39 -0600
|
|
Received: from subrogation.cygnus.com (subrogation.cygnus.com [192.80.44.76])
|
|
by tweedledumb.cygnus.com (8.8.5/8.8.5) with ESMTP id QAA18613;
|
|
Fri, 17 Apr 1998 16:18:12 -0400 (EDT)
|
|
Received: (ian@localhost) by subrogation.cygnus.com (950413.SGI.8.6.12/8.6.4) id QAA08387; Fri, 17 Apr 1998 16:18:11 -0400
|
|
Date: Fri, 17 Apr 1998 16:18:11 -0400
|
|
Message-Id: <199804172018.QAA08387@subrogation.cygnus.com>
|
|
From: Ian Lance Taylor <ian@cygnus.com>
|
|
To: gord@profitpress.com
|
|
CC: bug-libtool@gnu.org
|
|
In-reply-to: <86k98oh6fy.fsf@trick.profitpress.com> (message from Gordon
|
|
Matzigkeit on 17 Apr 1998 08:24:33 -0600)
|
|
Subject: Re: libtool on cygwin32
|
|
Xref: trick.profitpress.com mail.libtool:1335
|
|
Lines: 30
|
|
X-Gnus-Article-Number: 2 Mon Nov 2 17:17:55 1998
|
|
|
|
From: Gordon Matzigkeit <gord@profitpress.com>
|
|
Date: 17 Apr 1998 08:24:33 -0600
|
|
|
|
>>>>> Ian Lance Taylor writes:
|
|
|
|
[...]
|
|
|
|
ILT> So, my choices are to use -no-undefined -lbfd everywhere, or to
|
|
ILT> use it only on Windows.
|
|
|
|
Would `-avoid-deps' (a proposed flag) give you what you want?
|
|
|
|
default = record inter-library dependencies on all platforms, if
|
|
possible.
|
|
|
|
-no-undefined = the dependency info provided is complete. Build
|
|
shared libraries on AIX and windows.
|
|
|
|
-avoid-deps = implies `-no-undefined'. However, avoid recording
|
|
inter-library dependencies unless they are required for building a
|
|
shared library.
|
|
|
|
Yes, that sounds like it will do what I need.
|
|
|
|
Somebody someday may want to record some library dependencies but not
|
|
others, in which case you would want
|
|
-avoid-deps -lfoo -no-avoid-deps -lbar
|
|
|
|
Ian
|
|
|
|
From nobody Wed Oct 14 16:45:40 1998
|
|
X-From-Line: ian@cygnus.com Mon Apr 27 16:24:19 1998
|
|
Return-Path: <ian@cygnus.com>
|
|
Delivered-To: gord@trick.profitpress.com
|
|
Received: (qmail 136 invoked from network); 27 Apr 1998 16:24:18 -0000
|
|
Received: from unknown (HELO bambam.m-tech.ab.ca) (127.0.0.1)
|
|
by localhost with SMTP; 27 Apr 1998 16:24:18 -0000
|
|
Received: from tweedledumb.cygnus.com (gateway.m-tech.ab.ca [10.0.0.1]) by bambam.m-tech.ab.ca (8.8.5/8.6.9) with ESMTP id JAA21924 for <gord@m-tech.ab.ca>; Mon, 27 Apr 1998 09:42:43 -0600
|
|
Received: from subrogation.cygnus.com (subrogation.cygnus.com [192.80.44.76])
|
|
by tweedledumb.cygnus.com (8.8.5/8.8.5) with ESMTP id LAA02934;
|
|
Mon, 27 Apr 1998 11:48:04 -0400 (EDT)
|
|
Received: (ian@localhost) by subrogation.cygnus.com (950413.SGI.8.6.12/8.6.4) id LAA01776; Mon, 27 Apr 1998 11:48:03 -0400
|
|
Date: Mon, 27 Apr 1998 11:48:03 -0400
|
|
Message-Id: <199804271548.LAA01776@subrogation.cygnus.com>
|
|
From: Ian Lance Taylor <ian@cygnus.com>
|
|
To: gord@m-tech.ab.ca
|
|
CC: robbe@orcus.priv.at, bug-libtool@gnu.org
|
|
In-reply-to: <86bttpvbqd.fsf@trick.profitpress.com> (message from Gordon
|
|
Matzigkeit on 25 Apr 1998 15:21:30 -0600)
|
|
Subject: Re: libtool 1.2: Why no inter-lib dependencies on ELF?
|
|
Xref: trick.profitpress.com mail.libtool:1388
|
|
Lines: 27
|
|
X-Gnus-Article-Number: 3 Mon Nov 2 17:17:55 1998
|
|
|
|
From: Gordon Matzigkeit <gord@m-tech.ab.ca>
|
|
Date: 25 Apr 1998 15:21:30 -0600
|
|
|
|
There are still some unresolved issues (see
|
|
http://www.profitpress.com/libtool/deplibs.html). Full inter-library
|
|
dependency support is scheduled for libtool 1.3, though, and should
|
|
appear in the next beta-testing release.
|
|
|
|
I read that page, and here are a few quick notes.
|
|
|
|
1) On any platform which does not require -fpic you can link
|
|
static libraries into shared libraries. These platforms include
|
|
AIX, Irix 5/6, and Windows.
|
|
|
|
2) On any functioning ELF platform you can include code which was not
|
|
compiled with -fpic in a shared library, and you can link with a
|
|
static library when creating a shared library. You say that Solaris
|
|
won't let you link a shared library against a static one, but it
|
|
appears to work for me. What type of test are you using?
|
|
|
|
3) On SunOS you can not correctly link a static library into a shared
|
|
library. It will mostly work, but I believe that certain operations,
|
|
such as overriding a shared library function in the main executable,
|
|
will fail.
|
|
|
|
Ian
|
|
|
|
From nobody Wed Oct 14 16:48:43 1998
|
|
X-From-Line: gord@gnu.org Thu Sep 10 04:39:20 1998
|
|
Return-Path: <gord@gnu.org>
|
|
Delivered-To: gord@trick.fig.org
|
|
Received: (qmail 30644 invoked from network); 10 Sep 1998 04:39:18 -0000
|
|
Received: from gen2-93ip34.cadvision.com (HELO bambam.m-tech.ab.ca) (209.91.93.34)
|
|
by cs366707-a.cgmo1.ab.wave.home.com with SMTP; 10 Sep 1998 04:39:18 -0000
|
|
Received: from mescaline.gnu.org (gateway [10.0.0.1]) by bambam.m-tech.ab.ca (8.8.5/8.6.9) with ESMTP id WAA26741 for <gord@m-tech.ab.ca>; Wed, 9 Sep 1998 22:38:15 -0600
|
|
Received: from mailhost.cyberramp.net (root@mailhost.cyberramp.net [207.158.64.11]) by mescaline.gnu.org (8.8.5/8.6.12GNU) with ESMTP id AAA11165 for <bug-libtool@gnu.org>; Thu, 10 Sep 1998 00:38:17 -0400
|
|
Received: from fuzzylog.simple.dallas.tx.us (dal-tsa11-49.cyberramp.net [207.158.111.49])
|
|
by mailhost.cyberramp.net (8.9.1a/8.9.1/ler-980825-0832-PM) with ESMTP id XAA13581;
|
|
Wed, 9 Sep 1998 23:37:41 -0500 (CDT)
|
|
Received: from scooby (scooby [192.168.1.3])
|
|
by fuzzylog.simple.dallas.tx.us (8.8.8/8.8.8) with SMTP id XAA27692;
|
|
Wed, 9 Sep 1998 23:37:38 -0500 (CDT)
|
|
Date: Wed, 9 Sep 1998 23:37:38 -0500 (CDT)
|
|
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
|
|
To: Libtool Bugs <bug-libtool@gnu.org>
|
|
Subject: Late-binding looses space efficiency ...
|
|
Message-ID: <Pine.SO4.4.02.9809092322490.808-100000@scooby.simple.dallas.tx.us>
|
|
MIME-Version: 1.0
|
|
Content-Type: TEXT/PLAIN; charset=US-ASCII
|
|
Xref: trick.fig.org libtool:1605
|
|
Lines: 27
|
|
X-Gnus-Article-Number: 4 Mon Nov 2 17:17:55 1998
|
|
|
|
On most systems, libtool does not supply the dependency libraries (-llib) when
|
|
it creates the shared library in spite of these being supplied on the libtool
|
|
command line. The ImageMagick package uses quite a few dependency libraries.
|
|
The ImageMagick library uses these libraries directly but utilities built
|
|
using the ImageMagick library only link against these libraries because the
|
|
ImageMagick library demands it.
|
|
|
|
Through testing we have found that if the 'ltconfig' archive_cmds definition
|
|
is ammended to include $deplibs that linked programs become much smaller (1/3
|
|
to 1/4 the original size). This appears to be because more code is included
|
|
in the shared library itself, avoiding the need for this to be part of the
|
|
program.
|
|
|
|
The distributed 'ltconfig' only supplies $deplibs for systems matching osf3* |
|
|
osf4*. Is there a reason why $deplibs is not supplied for all systems that can
|
|
support inter-library dependencies? Reducing overall package size is highly
|
|
desireable in order to reduce disk-space consumption and binary distribution
|
|
size.
|
|
|
|
Thanks,
|
|
|
|
Bob
|
|
======================================
|
|
Bob Friesenhahn
|
|
bfriesen@simple.dallas.tx.us
|
|
http://www.cyberramp.net/~bfriesen
|
|
|
|
From nobody Wed Oct 14 16:52:40 1998
|
|
X-From-Line: ddj@hks.net Thu Sep 17 21:29:13 1998
|
|
Return-Path: <ddj@hks.net>
|
|
Delivered-To: gord@trick.fig.org
|
|
Received: (qmail 22994 invoked by uid 1003); 17 Sep 1998 21:29:12 -0000
|
|
Delivered-To: jana-profitpress-gord@profitpress.com
|
|
Received: (qmail 22991 invoked from network); 17 Sep 1998 21:29:11 -0000
|
|
Received: from dali.hks.net (ddj@208.203.175.210)
|
|
by cs366707-a.cgmo1.ab.wave.home.com with SMTP; 17 Sep 1998 21:29:11 -0000
|
|
Received: (from ddj@localhost)
|
|
by dali.hks.net (8.8.5/8.8.5) id RAA04020;
|
|
Thu, 17 Sep 1998 17:26:28 -0400
|
|
Received: from BatMail.robin.v2.15.CUILIB.3.45.SNAP.NOT.LINKED.dali..none..ix86.Linux
|
|
via MS.5.6.dali.(none).ix86_Linux;
|
|
Thu, 17 Sep 1998 17:26:27 -0400 (EDT)
|
|
Message-ID: <oq0Lu3Jz000185PkIG@hks.net>
|
|
Date: Thu, 17 Sep 1998 17:26:27 -0400 (EDT)
|
|
From: Doug DeJulio <ddj@hks.net>
|
|
To: gord@profitpress.com
|
|
Subject: Re: Libtool Inter-library Dependencies
|
|
Xref: trick.fig.org libtool:1611
|
|
Lines: 32
|
|
X-Gnus-Article-Number: 5 Mon Nov 2 17:17:55 1998
|
|
|
|
I read your discussion of why libtool can't handle inter-library
|
|
dependencies and how people might be able to help fix this. I found
|
|
an error in item #1 of "The Solution". I quote:
|
|
|
|
> Finally, there are some systems which won't even allow you to link a
|
|
> shared library against a static one:
|
|
> Solaris 2.x
|
|
|
|
This is only true in most cases. If all of the accessed individual
|
|
object files in the static library *could* have been put in a shared
|
|
library, things will work just fine. It's not the type of library
|
|
that matters, but the type of object files.
|
|
|
|
Our commercial product includes a library and a few
|
|
dynamically-loadable modules that make that library accessible to
|
|
various interpretetd languages (TCL, Perl, PHP3 and Python at the
|
|
moment, with more coming). We don't distribute a shared library
|
|
anymore because when we did this caused a ton of trouble (most people
|
|
just couldn't get it configured correctly). I haven't yet found a
|
|
platform on which linking dynamically-loadable object file against a
|
|
static "ar" archive containing relocatable object files causes any
|
|
trouble (and we support SCO, Digital Unix, SCO, Solaris, Linux, and
|
|
FreeBSD, so this isn't because of narrow experience).
|
|
|
|
So, the main point is that just deciding whether it'll work based on
|
|
looking at the library file will in some cases fail when it should
|
|
have succeeded (and the software we sell is such a case).
|
|
|
|
--
|
|
Doug DeJulio | mailto:ddj@hks.net
|
|
HKS, Incorporated | http://www.hks.net/
|
|
|
|
From gord@trick.fig.org Wed Nov 4 16:50 EDT 1998
|
|
Received: from grande.dcc.unicamp.br (grande.dcc.unicamp.br [143.106.7.8])
|
|
by amazonas.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id QAA12687
|
|
for <oliva@amazonas.dcc.unicamp.br>; Wed, 4 Nov 1998 16:50:18 -0200 (EDT)
|
|
Received: from cabler.cableregina.com (ip2.net20483142.cr.sk.ca [204.83.142.2])
|
|
by grande.dcc.unicamp.br (8.8.5/8.8.5) with SMTP id QAA03463
|
|
for <oliva@dcc.unicamp.br>; Wed, 4 Nov 1998 16:50:12 -0200 (EDT)
|
|
Received: from [24.72.10.223] by cabler.cableregina.com
|
|
(SMTPD32-4.0) id A25C7D0074; Wed, 04 Nov 1998 12:52:12 -0600
|
|
Received: (qmail 1392 invoked by uid 1001); 4 Nov 1998 18:51:16 -0000
|
|
To: "Gary V. Vaughan" <gvaughan@oranda.demon.co.uk>
|
|
Cc: Ian Lance Taylor <ian@cygnus.com>, tanner@gmx.de, oliva@dcc.unicamp.br,
|
|
bug-libtool@gnu.org
|
|
Subject: Re: Inter-library dependencies in libtool
|
|
References: <199811040125.UAA01678@subrogation.cygnus.com> <3640381C.725FC8F2@oranda.demon.co.uk>
|
|
X-Attribution: Gord
|
|
Mime-Version: 1.0 (generated by tm-edit 7.106)
|
|
From: Gordon Matzigkeit <gord@trick.fig.org>
|
|
Date: 04 Nov 1998 12:51:11 -0600
|
|
In-Reply-To: "Gary V. Vaughan"'s message of Wed, 04 Nov 1998 11:18:52 +0000
|
|
Message-ID: <86af27qokg.fsf@trick.fig.org>
|
|
X-Mailer: Gnus v5.5/Emacs 20.2
|
|
Content-Type: text/plain; charset=US-ASCII
|
|
X-Content-Length: 2911
|
|
Xref: araguaia.dcc.unicamp.br libtool-deplibs:6
|
|
Lines: 80
|
|
X-Gnus-Article-Number: 6 Thu Nov 5 08:41:15 1998
|
|
|
|
Hi!
|
|
|
|
>>>>> Gary V Vaughan writes:
|
|
|
|
GVV> Ian Lance Taylor wrote:
|
|
|
|
>> This kind of goes to the heart of libtool. libtool wants to
|
|
>> present a particular interface for using shared libraries.
|
|
|
|
GVV> Is that an "official" design goal?
|
|
|
|
Yes. From the manual:
|
|
|
|
1. The system must be as elegant as possible.
|
|
|
|
The main power of libtool is that it blurs the distinction between
|
|
static archives (`.a' files) and shared libraries, by providing an
|
|
interface that unifies the two into a new beast, the `.la' file. This
|
|
is the reason why libtool caught on: you can write Makefile rules that
|
|
work for both shared and static libraries.
|
|
|
|
>> In order to do this, it assumes that the system supports certain
|
|
>> capabilities. One of those is that the system can support
|
|
>> undefined symbols in shared libraries.
|
|
|
|
To add to this point: or the system can link shared libraries against
|
|
one another (deplibs).
|
|
|
|
GVV> My understanding was that libtool wants to provide a single
|
|
GVV> interface for the building of shared libraries, particularly so
|
|
GVV> that a developer can use libtool in a Makefile (*without* all of
|
|
GVV> the system dependant rules that used to me necessary) and get
|
|
GVV> shared libraries on all of libtool's supported platforms using
|
|
GVV> the same build rules.
|
|
|
|
Both your understandings are correct.
|
|
|
|
>> That means that on systems which do not permit shared libraries to
|
|
>> have undefined symbols--AIX and Windows--libtool doesn't really
|
|
>> work.
|
|
|
|
I would state this somewhat differently: on those platforms, libtool
|
|
works (it can still build static libraries), but it doesn't shine.
|
|
|
|
>> [[snip]] In other words, the interface which libtool presents is
|
|
>> deficient. It does not successfully hide the system on which it
|
|
>> is running, and it forces the code which calls libtool to make
|
|
>> adjustments.
|
|
|
|
Exactly.
|
|
|
|
I believe the correct way to solve this problem is to.... (drum roll)
|
|
use inter-library dependencies!
|
|
|
|
If `deplibs' is set, then the library has undefined symbols. If it
|
|
isn't set, then we could assume it has no undefined symbols.
|
|
|
|
So, using `-lanything' on the .la creation line would be a synonym for
|
|
`-allow-undefined', and having no `-l' flags would be a synonym for
|
|
`-no-undefined'.
|
|
|
|
>> Of course even that will not make Windows DLLs identical to ELF
|
|
>> shared libraries. ELF shared libraries permit the main program to
|
|
>> override a symbol in the shared library, and Windows DLLs do not.
|
|
|
|
I'd just as soon cross that bridge when we come to it, unless you have
|
|
any real-world examples that demand more control over whether or not
|
|
DLLs are built.
|
|
|
|
In any event, this is more incentive for Thomas Tanner's patches to
|
|
restrict the symbol table, so that people don't get bitten by
|
|
namespace clashes.
|
|
|
|
Thanks for your comments,
|
|
|
|
--
|
|
Gordon Matzigkeit <gord@fig.org> //\ I'm a FIG (http://www.fig.org/)
|
|
Lovers of freedom, unite! \// I use GNU (http://www.gnu.org/)
|
|
|
|
From ian@cygnus.com Wed Nov 4 17:16 EDT 1998
|
|
Received: from grande.dcc.unicamp.br (grande.dcc.unicamp.br [143.106.7.8])
|
|
by amazonas.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id RAA17371
|
|
for <oliva@amazonas.dcc.unicamp.br>; Wed, 4 Nov 1998 17:15:59 -0200 (EDT)
|
|
Received: from tweedledumb.cygnus.com (tweedledumb.cygnus.com [192.80.44.1])
|
|
by grande.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id RAA04425
|
|
for <oliva@dcc.unicamp.br>; Wed, 4 Nov 1998 17:15:45 -0200 (EDT)
|
|
Received: from subrogation.cygnus.com (subrogation.cygnus.com [192.80.44.76])
|
|
by tweedledumb.cygnus.com (8.8.5/8.8.5) with ESMTP id OAA16598;
|
|
Wed, 4 Nov 1998 14:17:48 -0500 (EST)
|
|
Received: (ian@localhost) by subrogation.cygnus.com (950413.SGI.8.6.12/8.6.4) id OAA02450; Wed, 4 Nov 1998 14:17:48 -0500
|
|
Date: Wed, 4 Nov 1998 14:17:48 -0500
|
|
Message-Id: <199811041917.OAA02450@subrogation.cygnus.com>
|
|
From: Ian Lance Taylor <ian@cygnus.com>
|
|
To: gord@trick.fig.org
|
|
CC: gvaughan@oranda.demon.co.uk, tanner@gmx.de, oliva@dcc.unicamp.br,
|
|
bug-libtool@gnu.org
|
|
In-reply-to: <86af27qokg.fsf@trick.fig.org> (message from Gordon Matzigkeit on
|
|
04 Nov 1998 12:51:11 -0600)
|
|
Subject: Re: Inter-library dependencies in libtool
|
|
X-Content-Length: 1774
|
|
Xref: araguaia.dcc.unicamp.br libtool-deplibs:7
|
|
Lines: 43
|
|
X-Gnus-Article-Number: 7 Thu Nov 5 08:41:16 1998
|
|
|
|
From: Gordon Matzigkeit <gord@trick.fig.org>
|
|
Date: 04 Nov 1998 12:51:11 -0600
|
|
|
|
I believe the correct way to solve this problem is to.... (drum roll)
|
|
use inter-library dependencies!
|
|
|
|
If `deplibs' is set, then the library has undefined symbols. If it
|
|
isn't set, then we could assume it has no undefined symbols.
|
|
|
|
So, using `-lanything' on the .la creation line would be a synonym for
|
|
`-allow-undefined', and having no `-l' flags would be a synonym for
|
|
`-no-undefined'.
|
|
|
|
This sounds reasonable. Of course, -allow-undefined should remain a
|
|
possible option even if there are no -l options. I guess
|
|
-no-undefined could be an error check, but it wouldn't have much
|
|
functional use.
|
|
|
|
>> Of course even that will not make Windows DLLs identical to ELF
|
|
>> shared libraries. ELF shared libraries permit the main program to
|
|
>> override a symbol in the shared library, and Windows DLLs do not.
|
|
|
|
I'd just as soon cross that bridge when we come to it, unless you have
|
|
any real-world examples that demand more control over whether or not
|
|
DLLs are built.
|
|
|
|
In any event, this is more incentive for Thomas Tanner's patches to
|
|
restrict the symbol table, so that people don't get bitten by
|
|
namespace clashes.
|
|
|
|
What I'm talking about is not namespace clashes, but rather the
|
|
ability to override a particular function from a shared library. For
|
|
example, I can write my own version of malloc and free, and libc.so on
|
|
an ELF system will use them rather than the malloc and free linked
|
|
into the library.
|
|
|
|
I don't think there is anything libtool can do about this. It's
|
|
something that is very useful when dealing with preexisting shared
|
|
libraries, but is not particularly useful when dealing with shared
|
|
libraries you build yourself.
|
|
|
|
Ian
|
|
|
|
From gord@mescaline.gnu.org Thu Nov 5 15:32 EDT 1998
|
|
Received: from grande.dcc.unicamp.br (grande.dcc.unicamp.br [143.106.7.8])
|
|
by amazonas.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id PAA10607
|
|
for <oliva@amazonas.dcc.unicamp.br>; Thu, 5 Nov 1998 15:32:00 -0200 (EDT)
|
|
Received: from mescaline.gnu.org (mescaline.gnu.org [158.121.106.21])
|
|
by grande.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id PAA22399
|
|
for <oliva@dcc.unicamp.br>; Thu, 5 Nov 1998 15:31:57 -0200 (EDT)
|
|
Received: from hades.aethos.co.uk (hades.aethos.co.uk [195.171.18.1] (may be forged))
|
|
by mescaline.gnu.org (8.9.1a/8.9.1) with ESMTP id MAA01615
|
|
for <bug-libtool@gnu.org>; Thu, 5 Nov 1998 12:37:11 -0500
|
|
Received: from zeus.aethos.co.uk (zeus.aethos.co.uk [193.164.192.100])
|
|
by hades.aethos.co.uk (8.8.5/8.8.5) with ESMTP id RAA28242;
|
|
Thu, 5 Nov 1998 17:37:46 GMT
|
|
Received: from oranda.demon.co.uk (samhain.aethos.co.uk [193.164.192.38]) by zeus.aethos.co.uk with ESMTP (8.7.1/8.7.1) id RAA03467; Thu, 5 Nov 1998 17:33:25 GMT
|
|
Message-ID: <3641E0DF.A8F92E78@oranda.demon.co.uk>
|
|
Date: Thu, 05 Nov 1998 17:31:11 +0000
|
|
From: "Gary V. Vaughan" <gvaughan@oranda.demon.co.uk>
|
|
Organization: Aethos Communication Systems ltd.
|
|
X-Mailer: Mozilla 4.5 [en] (WinNT; I)
|
|
X-Accept-Language: en
|
|
MIME-Version: 1.0
|
|
To: Alexandre Oliva <oliva@dcc.unicamp.br>
|
|
CC: Ian Lance Taylor <ian@cygnus.com>, tanner@gmx.de, gord@trick.fig.org,
|
|
bug-libtool@gnu.org
|
|
Subject: Re: Inter-library dependencies in libtool
|
|
References: <199811041854.NAA02418@subrogation.cygnus.com> <364183EF.9F15E7D6@oranda.demon.co.uk> <orhfweny1t.fsf@araguaia.dcc.unicamp.br>
|
|
Content-Transfer-Encoding: 7bit
|
|
Content-Type: text/plain; charset=us-ascii
|
|
X-Content-Length: 3787
|
|
Xref: araguaia.dcc.unicamp.br libtool-deplibs:8
|
|
Lines: 87
|
|
X-Gnus-Article-Number: 8 Sat Nov 7 05:46:44 1998
|
|
|
|
If I may be permitted to quote you gratuitously... I think there are two
|
|
problems here, and solving the first will keep most people happy most of
|
|
the time.
|
|
|
|
In order of progressive difficulty...
|
|
|
|
1. COMPILE TIME LTLIBRARIES
|
|
***************************
|
|
|
|
Alexandre Oliva wrote:
|
|
>
|
|
> [[1.1]] the programmer knows that his library is completely
|
|
> self-contained, it does not depend on any external symbols
|
|
> (-no-undefined)
|
|
|
|
1.2) The link mode command line to libtool contains no -l options,
|
|
which implies your fallback method (try to link a shared library
|
|
as if `-no-undefined' had been specified, or if that fails build
|
|
only a static library).
|
|
|
|
1.3) The programmer knows that resolving all of the symbols in his
|
|
library requires linking deplibs, and is able to specify all of
|
|
them on the link line (some if these may be installed .la files
|
|
which have deplibs of their own which libtool must also link
|
|
with).
|
|
|
|
> [[1.4]] the programmer knows that there may be symbols in his library
|
|
> that are going to be supplied by another library, which [[is]]
|
|
> unknown in advance. If such dependencies exist, they have to
|
|
> be resolved at program-linking time (-allow-undefined == default)
|
|
|
|
In the future maybe libtool will be able to do a two stage link
|
|
for platforms which can't do `-allow-undefined', the first link
|
|
to find which symbols are unresolved, the second against a
|
|
temporarily generated set of stubs... I'm not sure whether the
|
|
stage 2 lib can then resolve its stubbed functions against a
|
|
different library when it is subsequently linked into an
|
|
executable? Perhaps I am reiterating Ian's idea about stubbing
|
|
on broken platforms?
|
|
|
|
In the present, broken platforms will have to manage with static
|
|
libraries in this case.
|
|
|
|
2. RUNTIME LTLIBRARIES
|
|
**********************
|
|
|
|
> [[2.1]] the programmer needs a library foo that is completely
|
|
> self-contained, so that he can be sure that dlopen(foo) works,
|
|
> and just adding -lfoo *after* the library is installed will be
|
|
> fine (-self-contained ?)
|
|
|
|
2.2) The programmer needs a library that can be dlopened, but which
|
|
can have all of its symbols resolved at link time with deplibs.
|
|
A small amount of magic in the form a .c and .h distributed with
|
|
libtool (as suggested by Gord) is enough to make sure deplibs
|
|
are dlopened if necessary and then the library itself is loaded.
|
|
At best, this will only be supported on platforms for which
|
|
libtool can generate shared libraries, perhaps only a (large)
|
|
subset of those.
|
|
|
|
2.3) The programmer needs a library that can be dlopened, and
|
|
doesn't know at link time how all of the symbols will be resolved.
|
|
A (small) subset of the platforms for which libtool can generate
|
|
shared libraries, will be handled by the aforementioned magic.
|
|
For the unhandled cases dld will be required.
|
|
|
|
> [[2.4]] although a library is not going to be self-contained,
|
|
> [[snip]] the platform does not support libraries with undefined
|
|
> symbols, a shared library is badly needed, [[This will]] require
|
|
> dld.
|
|
|
|
NOTE: in the above, I am assuming that
|
|
all-supported-platforms >= (large) >= (small) > no-platforms
|
|
|
|
I don't see any need to add anymore command line switches, except
|
|
perhaps to tell libtool whether this is a compile time or runtime
|
|
library, but even that may prove unnecessary.
|
|
|
|
The line between 1.3 and 1.4 could probably use some clarification; what
|
|
if the link line includes several deplibs, but some symbols are
|
|
still unresolved? 1.4? Maybe... what if the platform doesn't support
|
|
`-no-undefined'? Perhaps there is a 1.3.5? In any case, for maximum
|
|
portability, we want to keep the number of cases of 1.4 to a minimum.
|
|
|
|
Cheers,
|
|
Gary.
|
|
|
|
From wmperry@aventail.com Sun Nov 1 01:03 EDT 1998
|
|
Received: from grande.dcc.unicamp.br (grande.dcc.unicamp.br [143.106.7.8])
|
|
by amazonas.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id BAA29973
|
|
for <oliva@amazonas.dcc.unicamp.br>; Sun, 1 Nov 1998 01:03:04 -0200 (EDT)
|
|
Received: from slow.bp.aventail.com (vina05.cntwk.net [207.205.120.131])
|
|
by grande.dcc.unicamp.br (8.8.5/8.8.5) with ESMTP id BAA10397
|
|
for <oliva@dcc.unicamp.br>; Sun, 1 Nov 1998 01:02:59 -0200 (EDT)
|
|
Received: from kramer-fast.bp.aventail.com (kramer-fast.bp.aventail.com [192.168.200.2])
|
|
by slow.bp.aventail.com (8.8.5/8.8.5) with ESMTP id SAA31093;
|
|
Sat, 31 Oct 1998 18:03:52 -0800
|
|
Received: (from wmperry@localhost)
|
|
by kramer-fast.bp.aventail.com (8.8.5/8.8.5) id WAA21542;
|
|
Sat, 31 Oct 1998 22:04:49 -0500
|
|
Sender: wmperry@aventail.com
|
|
To: Gordon Matzigkeit <gord@trick.fig.org>
|
|
Cc: Alexandre Oliva <oliva@dcc.unicamp.br>
|
|
Subject: Re: libtool 1.2 problems...
|
|
References: <199810251708.MAA02237@kramer-fast.bp.aventail.com> <oryapxaste.fsf@araguaia.dcc.unicamp.br> <86zpac2z99.fsf@trick.fig.org>
|
|
Errors-to: wmperry@aventail.com
|
|
Reply-to: wmperry@aventail.com
|
|
X-Face: O~Rn;(l][/-o1sALg4A@xpE:9-"'IR[%;,,!m7</SYF`{vYQ(&RI1&EiH[FvT;J}@f!4kfz
|
|
x_!Y#=y{Uuj9GvUi=cPuajQ(Z42R[wE@{G,sn$qGr5g/wnb*"*ktI+,CD}1Z'wxrM2ag-r0p5I6\nA
|
|
[WJopW_J.WY;
|
|
Mime-Version: 1.0 (generated by tm-edit 7.108)
|
|
From: wmperry@aventail.com (William M. Perry)
|
|
Date: 31 Oct 1998 22:04:49 -0500
|
|
In-Reply-To: Gordon Matzigkeit's message of "31 Oct 1998 15:32:50 -0600"
|
|
Message-ID: <867lxgazam.fsf@kramer-fast.bp.aventail.com>
|
|
X-Mailer: Gnus v5.6.8/XEmacs 21.0 - "Pyrenean-pre6"
|
|
Content-Type: text/plain; charset=US-ASCII
|
|
X-Content-Length: 2306
|
|
Xref: araguaia.dcc.unicamp.br libtool-deplibs:9
|
|
Lines: 66
|
|
X-Gnus-Article-Number: 9 Fri Nov 20 23:23:12 1998
|
|
|
|
Gordon Matzigkeit <gord@trick.fig.org> writes:
|
|
|
|
> >>>>> Alexandre Oliva writes:
|
|
>
|
|
> AO> I can understand why we'd want all that stuff on systems with
|
|
> AO> brain-damaged dynamic linkers or such, but on Linux? Gord?
|
|
>
|
|
> No specific reason. I was trying to implement something that would
|
|
> work on all platforms, including Linux.
|
|
>
|
|
> >> I think optionally having a PUBLIC_API preprocessor macro or
|
|
> >> something might be handy.
|
|
>
|
|
> AO> Thomas Tanner has recently submitted a patch that implements
|
|
> AO> that, I think. I still couldn't find the time to look carefully
|
|
> AO> at the patch, but, from the text description, it looks like
|
|
> AO> that's exactly what it does.
|
|
>
|
|
> I think it's a good idea to be able to specify global symbols
|
|
> explicitly. That's part of the glibc versioning system that I was
|
|
> alluding to earlier.
|
|
>
|
|
> If you look at the `--version-script' option to GNU ld
|
|
> ((ld.info)Version Script.), then you'll see more details.
|
|
|
|
To restrict globally visible symbols, here's the info I've got. :) i've
|
|
been using this for quite a while in our server product. All hail the
|
|
NSA.
|
|
|
|
Linux: '--retain-symbols-file <FILENAME>' , with all the symbols you want
|
|
exported in <FILENAME>
|
|
|
|
OSF1: '-hidden -exported_symbol "symname-or-wildcardspec"'
|
|
|
|
AIX: you just restrict what you but in the export list you pass to
|
|
-bE:<FILENAME>.
|
|
|
|
HP/UX: '+e symname' on the link line for each exported symbol you want
|
|
|
|
Solaris: create a map file for the linker that looks like:
|
|
{
|
|
global:
|
|
symname1;
|
|
symname2;
|
|
symname3;
|
|
local:
|
|
*;
|
|
}
|
|
|
|
And use -M <MAPFILE> on the link line.
|
|
|
|
BSD/OS 3.x is the only system I couldn't find a way to support this symbol
|
|
hiding on. But you might be able to do it better with BSD/OS 4.x now that
|
|
they have finally moved to elf.
|
|
|
|
BTW: What are the subscription directions for libtool-bugs or a general
|
|
discussion list for stuff like this? I've had lots of experience over the
|
|
last 3 years with dynamic loading on various platforms, and would love to
|
|
get libtool to the point where I could use it for all of our products here
|
|
at aventail. Less stuff for me to officially maintain. :)
|
|
|
|
I'd also like to see DLD 4.x eventually so that I can just support it and
|
|
ditch all the crufty junk we are using right now. :) Abstraction good.
|
|
|
|
-Bill P.
|
|
|