The generator expression `$<CONFIG>` is not evaluated to `CMAKE_BUILD_TYPE` when used in the sources of a library target that is linked by another target. Small example project: [cmakeConfigLibBug.tar.gz](/uploads/014dc07c7bfe0c7275cb17ddad81d7d0/cmakeConfigLibBug.tar.gz) **CMakeLists.txt from the example** ``` cmake_minimum_required ( VERSION 3.7.2 ) # Set build type set(CMAKE_BUILD_TYPE Debug) # Library with $<CONFIG> fails add_library(libA STATIC libA_$<CONFIG>.cpp) # Executable that links to library add_executable ( binA main.cpp ) target_link_libraries(binA libA) ``` This is a roadblock for https://gitlab.kitware.com/cmake/cmake/merge_requests/858