Re: include the right ltdl.h

[Ralf Wildenhues]

Hello Eric,

* Eric Blake wrote on Tue, Jun 13, 2006 at 03:30:17PM CEST:
> According to Ralf Wildenhues on 6/13/2006 3:08 AM:
> > This patch makes sure you use the in-tree ltdl.h if necessary,
> > thus fixing a build failure (e.g., if the ltdl.h that is found in the
> > default paths is an old one, or none is found there).
> 
> And it is a fairly old patch; you submitted the same idea several months
> ago, and it is still sitting in my local tree, unchecked in.

And it's documented in libtool.info that this is necessary.  And on my
system it fixes a hard build failure, because the installed ltdl.h is
from 1.5.x (and I don't intend to change that, for obvious bug exposure
reasons):

| libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I../m4 -I. -I. -I../m4 -Ignu 
-I../m4/gnu -Im4 -I../m4/m4 -O2 -pipe -MT m4/module.lo -MD -MP -MF 
m4/.deps/module.Tpo -c ../m4/m4/module.c  -fPIC -DPIC -o m4/.libs/module.o
| ../m4/m4/module.c:94: error: syntax error before "iface_id"
| ../m4/m4/module.c:94: warning: data definition has no type or storage class
| ../m4/m4/module.c: In function `m4__module_next':
| ../m4/m4/module.c:297: warning: return makes pointer from integer without a 
cast
| ../m4/m4/module.c: In function `m4__module_find':
| ../m4/m4/module.c:307: warning: return makes pointer from integer without a 
cast

> And as a wish, it would be nice if libtoolize would be more verbose
> about mentioning that this must be added to Makefile.am if it detects
> that automake was in use.

Hmm.  For now I am working on making libtoolize less verbose,
i.e., killing all those possibly-wrong notices it still spits out.
I'm not very keen on adding warnings; the more babble you output,
the less users are inclined to read.  Reading the manual instead
is unobtrusive, and you have to read that section anyway if you
intend to use libltdl successfully -- there are far more intricate
gotchas there than the need for LTDLINCL.

Cheers,
Ralf