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if the define BOOST_USE_XYZ is given at b2/bjam command-line how can I set special compiler- and linker-flags in the Jamfile?

something like this:

Jamfile.v2:

*project boost/abc : requirements <toolset>gcc-4.7,<defined>BOOST_USE_XYZ:<cxxflags>-fxyz <toolset>gcc-4.7,<defined>BOOST_USE_XYZ:<linkflags>"-static-libxyz" <link>static <threading>multi : source-location ../src : usage-requirements <link>shared:<define>BOOST_ABC_DYN_LINK=1 ; * if the lib is build with b2 toolset=gcc cxxflags="-DBOOST_USE_XYZ" then -fxyz static-libxyz is applied to the compiler otherwise not. How can I achieve this behaviour?

You should use define=BOOST_USE_XYZ instead of cxxflags, and <define>BOOST_USE_XYZ in the Jamfile. However, it's probably to use

feature xyz : on : optional propagated composite ; feature.compose <xyz>on : <define>BOOST_USE_XYZ ; <toolset>gcc-4.7,<xyz>on:<cxxflags>-fxyz ... bjam ... xyz=on ...

really nice - thank you! Does an convention exist how such thing like BOOST_USE_XYZ should be named, e.g. BOOST_USE_XYZ should enable segmented stack for boost.coroutine. Might bjam ... use_segmented_stacks=on be OK? (I didn't found a hint about naming in the documentation). best regards, Oliver