[boost] [Config][auto_link] BOOST_LIB_TOOLSET override does not work as intended when multiple libraries are used

From: Sean Huang (huangsean_at_[hidden])
Date: 2005-08-12 01:00:43

For example, if BOOST_LIB_TOOLSET is defined as "iw90" and both thread and 
signals libraries are used in a cpp file, compiler prints out the following:

Linking to lib file: libboost_thread-iw90-mt-s-1_33.lib
Linking to lib file: libboost_signals-iw-mt-s-1_33.lib

The problem is caused by BOOST_LIB_TOOLSET being undefined at the end of 
auto_link.hpp. The second time auto_link.hpp is included  (it has no include 
guards and is meant to be included multiple times)  BOOST_LIB_TOOLSET is not 
defined anymore and a default value will be assigned. Does it really need to 
be undef'ed?

Thanks,

Sean