Re: Issue with libtool when cross-compiling

[Richard Purdie]

On Fri, 2010-02-12 at 16:34 +0100, Thomas Petazzoni wrote:
> I'm a contributor to the Buildroot project (http://www.buildroot.org),
> a build system for embedded Linux systems. We integrate many packages
> in order to ease their cross-compilation.
> 
> I'm facing an issue with several packages where libtool wants to link
> against libraries of the host (in /usr/lib), and I don't know what
> is happening. It is very likely a problem in the environment variables
> or the options we pass to the configure script, but I'm unable to find
> where the problem is, and thought that libtool experts might have an
> idea on what's going on.

libtool has known cross compile issues and doesn't get on well with
sysroots. 

I maintain the OpenEmbedded libtool patch set which at least lets us
work around the worst libtool issues. The main patch is:

http://git.pokylinux.org/cgit.cgi/poky/tree/meta/packages/libtool/libtool-2.2.6/cross_compile.patch

and there is a bugfix I've been meaning to look at in more detail which
became neccessary with recent autoconf/automake versions:

http://git.pokylinux.org/cgit.cgi/poky/tree/meta/packages/libtool/libtool-2.2.6/trailingslash.patch

where a trailing slash on paths causes a string comparison to fail. We
also apply: 

http://git.pokylinux.org/cgit.cgi/poky/tree/meta/packages/libtool/libtool-2.2.6/prefix.patch

which renames libtool and allows us to easily tell when the wrong
(unpatched) libtool is being used.

There are other workarounds we have to apply after installing packages,
particularly modifying the .la files to be uninstalled to get the
sysroot to work properly. I'd love to teach libtool about sysroots and
make it work properly but as yet have never had the time to look into
it.

Cheers,

Richard