# this enables only C, i.e. disables C++ project(SimpleCOnly C) add_library(SimpleCLib STATIC bar.c foo.c) add_executable(SimpleC main.c) target_link_libraries(SimpleC SimpleCLib) # and some check, just to make sure it works: include(CheckTypeSize) check_type_size(float SIZE_FLOAT) message(STATUS "sizeof(float): ${SIZE_FLOAT}") # make sure optimized libs are not used by debug builds if(CMAKE_BUILD_TYPE MATCHES Debug) target_link_libraries(Simple optimized c:/not/here.lib ) endif()