Hi all, I discovered a severe logic flaw in the generated CMake Config files for the new Boost 1.70 which make them almost unusable. As an example the static variant contains: if(NOT"${Boost_USE_STATIC_LIBS}"STREQUAL""ANDNOTBoost_USE_STATIC_LIBS) _BOOST_SKIPPED("libboost_filesystem.a""static, Boost_USE_STATIC_LIBS=${Boost_USE_STATIC_LIBS}") return() endif() if(BUILD_SHARED_LIBS) _BOOST_SKIPPED("libboost_filesystem.a""static, BUILD_SHARED_LIBS=${BUILD_SHARED_LIBS}, set Boost_USE_STATIC_LIBS=ON to override") return() endif() The shared variant contains: if(NOT"${Boost_USE_STATIC_LIBS}"STREQUAL""ANDBoost_USE_STATIC_LIBS) _BOOST_SKIPPED("libboost_filesystem.so.1.70.0""shared, Boost_USE_STATIC_LIBS=${Boost_USE_STATIC_LIBS}") return() endif() if(NOTBUILD_SHARED_LIBS) _BOOST_SKIPPED("libboost_filesystem.so.1.70.0""shared, BUILD_SHARED_LIBS not ON, set Boost_USE_STATIC_LIBS=OFF to override") return() endif() Although the message text says otherwise the 2nd return in both cases depends solely on BUILD_SHARED_LIBS. I'm pretty sure the intention was too check for BUILD_SHARED_LIBS *only* if Boost_USE_STATIC_LIBS is not set (see thread https://lists.boost.org/Archives/boost/2019/02/245030.php). As can be seen this is not the case. I haven't found the repo which contains the code that generates this so I can't report it there or fix it myself. As the issue here makes using Boost 1.70 (almost) impossible (in Scenarios like BUILD_SHARED_LIBS=ON (a CMake variable influencing the project build) and Boost_USE_STATIC_LIBS=ON) I'd recommend fixing this and pushing out a bugfix release. Regards, Alexander Grund