Re: [jamboost] Question on install-target-class

From: Vladimir Prus (ghost_at_[hidden])
Date: 2005-04-19 08:39:52

Hi Syomichev,
> I added some "echo" statements in the install-target-class.construct in
> order to see what targets are "install" target's sources. With a
> following Jamfile
> lib dyn : dyn.cpp : <link>shared ;
> lib stat : stat.cpp dyn : <link>static ;
> install dist-dyn : dyn ;
> install dist-stat : stat ;
> alias install : dist-dyn dist-stat ;
> "bjam install" shows that the second install target is composed of two
> source targets (when I would logically expect only one).
> My debug printout is:
> dist-dyn
> dyn.dll
> ---------
> dist-stat
> stat.a
> dyn.dll
> ---------
> Actually, I have two questions:
> 1) How does "dyn.dll" get listed as a source target to the "dist-stat"
> install target?

This is the way generators work. The 'dyn' target produces dyn.lib and 
dyn.dll. Whe 'stat' target consumes dyn.lib, but don't know what to do with 
dyn.dll, so it returns it together with stat.a. 

I have a patch that changes this behaviour and hope to commit it during this 
week.

> 2) Why there is no "duplicate target" error raised? What is the
> mechanism of the duplicate elimination?

The "duplicate target" error is raised when you have two targets that are 
assigned the same filename but differ either in the list of sources (which 
never happened so far), or in the list of 'free' properties, which happens 
quite often.

So,
exe a : a.cpp ;
exe b : a.cpp ;

generates no error, but

exe a : a.cpp : <define>FOO ;
exe b : a.cpp ;

generates an error.

HTH,
Volodya

-- 
Vladimir Prus
http://vladimir_prus.blogspot.com
Boost.Build V2: http://boost.org/boost-build2