Question on install-target-class

From: Alexey Syomichev (asyomichev_at_[hidden])
Date: 2005-04-18 21:26:24

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

Thank you
--Alexey