Try using rpath only for unix.

src/dtkLog/CMakeLists.txt

@@ -39,6 +39,7 @@ add_library(${PROJECT_NAME} SHARED
 
 set_target_properties(${PROJECT_NAME} PROPERTIES MACOSX_RPATH 0)
 set_target_properties(${PROJECT_NAME} PROPERTIES INSTALL_NAME_DIR "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}")
+set_target_properties(${PROJECT_NAME} PROPERTIES INSTALL_RPATH    "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}")
 
 ## ###################################################################
 ## Link rules