Re: Question regarding interdependent convenience libraries

[Bob Friesenhahn]

On Wed, 2 May 2007, Scott D. Fleming wrote:
> Is libtool or the underlying linker smart enough to recognize and
> ignore the duplicate libraries?

I think that the content of convenience libraries is extracted into 
individual .o files prior to being used for linkage.  They are not 
used for linking like traditional archive libraries.  This means that 
any duplicates would result in individual .o files being overwritten 
prior to use.  In other words non-fatal for building applications. 
However, if you build installed libraries based on these convenience 
libraries, you could run into trouble if two installed libraries 
included some of the same objects.

> Or, do I have a problem with my setup? If so, can anyone suggest a
> better one? (I am familiar with the technique that uses a top-level
> convenience library that aggregates the sub-libraries; documented
> here:

A radically-different solution is to use a non-recursive Makefile 
scheme.  This eliminates the need for convenience libraries entirely 
and speeds up the build.  Automake does support this reasonably well 
and you can use Makefile includes to still keep Makefile fragments 
alongside the sources.  However, the Makefile fragments require 
"namespacing" as if everything is referenced from the top level 
Makefile (which they will be).

Bob
======================================
Bob Friesenhahn
address@hidden, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/