I am using bjam to build my application on suse linux. I have defined a environment variable BOOST_ROOT, which allows me to switch between boost builds. I have used this approach for 1.38, 1.39,1.40. I always build the boost libraries I need myself using bjam. bjam --build-dir=./tmpBuildDir toolset=gcc stage link=static --with-system i.e I don't bother with build scripts in $BOOST_ROOT With 1.42 when I build my application I get an error of the form: error: Unable to find file or target named error: '/var/tmp/ma0/boost/boost_1_42_0/stage/lib/libboost_system.a' error: referred from project at error: '' The error is very misleading because the file exists? When I switch back, to 1.39/1.40 there are no problems. This is what my boost-build.jam look like: -------------------------------------------------------------------------------- BOOST_BUILD = [ MATCH --boost-build=(.*) : $(ARGV) ] ; BOOST_BUILD ?= $(BOOST_ROOT)/tools/build/v2 ; boost-build $(BOOST_BUILD) ; Here is jam file for my leaf project: ---------------------------------------------------------------------------- use-project theCore : ../ACore ; exe test : [ glob src/*.cpp ] /site-config//boost_system /site-config//boost_serialization : <include>../SCRATCH/src <variant>debug:<define>DEBUG ; -------------------------------------------------------------------------- Notice that I reference /site-config// to reference the boost libs. for some reason in 1.42 this fails ! My site-config.file which is located in $BOOST_ROOT/tools/build/v2 is of the form: ------------------------------------------------------------------------ import os ; local BOOST_ROOT = [ os.environ BOOST_ROOT ] ; lib boost_serialization : : <file>$(BOOST_ROOT)/stage/lib/libboost_serialization.a ; lib boost_system : : <file>$(BOOST_ROOT)/stage/lib/libboost_system.a ; project site-config : requirements <include>$(BOOST_ROOT) ; using gcc ; using testing ; -------------------------------------------------------------------- My site-config.jam is the same between 1.40 and 1.42. There is probably a silly mistake on my part somewhere, but its preventing me from moving to 1.42. Any help appreciated. Best regards, Ta, Avi