diff --git a/simgear/math/CMakeLists.txt b/simgear/math/CMakeLists.txt
index 0ebe7fd0..436b8f41 100644
--- a/simgear/math/CMakeLists.txt
+++ b/simgear/math/CMakeLists.txt
@@ -44,11 +44,18 @@ set(SOURCES
 simgear_component(math math "${SOURCES}" "${HEADERS}")
 
 if(ENABLE_TESTS)
+
+if (SIMGEAR_SHARED)
+    set(TEST_LIBS SimGearCore)
+else()
+    set(TEST_LIBS SimGearCore ${CMAKE_THREAD_LIBS_INIT})
+endif()
+
 add_executable(math_test SGMathTest.cxx)
-target_link_libraries(math_test SimGearCore)
+target_link_libraries(math_test ${TEST_LIBS})
 add_test(math ${EXECUTABLE_OUTPUT_PATH}/math_test)
 
 add_executable(geometry_test SGGeometryTest.cxx)
-target_link_libraries(geometry_test SimGearCore)
+target_link_libraries(geometry_test ${TEST_LIBS})
 add_test(geometry ${EXECUTABLE_OUTPUT_PATH}/geometry_test)
 endif(ENABLE_TESTS)