--- old/unittests/CMakeLists.txt
+++ new/unittests/CMakeLists.txt
@@ -1,4 +1,7 @@
 file(GLOB TESTS RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.cpp)
+if(NOT Boost_FOUND)
+ list(REMOVE_ITEM TESTS boost_variant.cpp)
+endif(Boost_FOUND)
 
 # A semi-colon separated list of test sources that should not be automatically built with doctest 
 set(SPECIAL_TESTS "portability_test.cpp")