[Boost-build] How to declare 3rd party libraries in the project-root.jam?

From: Cheng Lian (rhythm.mail_at_[hidden])
Date: 2007-04-23 23:38:30

Hi, all

I'm using bbv2 as my building system. But here is a question. The 
version is:

~$ bjam --version
Boost.Build V2 (Milestone 10)
Boost.Jam 03.01.11

It a bit old, but I'd like a somehow stable version. My project refers 
to some standard libraries, such as pthread and log4cxx. When I declare 
them in the site-config.jam like things below,
it all works:

# site-config.jam

import project ;

project.initialize $(__name__) ;
project site-config ;

lib pthread
     :
     :
     <name>pthread
     <search>/usr/lib
     ;

lib log4cxx
     :
     :
     <name>log4cxx
     <search>/usr/lib
     ;

# My project-root.jam

project
     :
     requirements
         <source>/site-config//boost_thread
         <source>/site-config//log4cxx
     :
     build-dir
         bin
     :
     default-build
         debug
     ;

But when I move these declarations into the project-root.jam like this:

# My proejct-root.jam

lib pthread
     :
     :
     <name>pthread
     <search>/usr/lib
     ;

lib log4cxx
     :
     :
     <name>log4cxx
     <search>/usr/lib
     ;

project
     :
     requirements
         <source>/site-config//boost_thread
         <source>/site-config//log4cxx
     :
     build-dir
         bin
     :
     default-build
         debug
     ;

Bjam complains things like this:

error: Unable to find file or target named
error:     'log4cxx'
error: referred from project at
error:     'server'

And I found out that if I move the the 3rd party library declarations 
into the sub project Jamfiles, it also works:

# My sub project Jamfile
lib pthread
     :
     :
     <name>pthread
     <search>/usr/lib
     ;

lib log4cxx
     :
     :
     <name>log4cxx
     <search>/usr/lib
     ;

project server
     :
     requirements
         <include>include
         <link>static
         <source>../util
         <source>log4cxx
         <source>pthread
     ;

exe server
     :
     [ glob src/*.cpp ]
     ;

How could I move standard library declaration into my project-root.jam? 
The document suggest that standard libraries should be declared in the
site-config.jam since the installation location may vary among systems.
But there're still reasons to declare some non-standard 3rd party in the 
project Jamfile, since I think it's no good to maintain a huge 
site-config.jam among several boxes with different OS running on, which 
is the very case that I am in.

Thanks for any clarifications!