diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index eb29252..a62c0de 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -8,7 +8,10 @@
 
 add_subdirectory(Interpreter)
 add_subdirectory(MetaProcessor)
-if(CLING_INCLUDE_TESTS)
-   add_subdirectory(UserInterface)
-endif()
+# The UserInterface library (clingUserInterface) is linked unconditionally by the
+# cling driver, so it must always be built. Upstream cling 1.3 mistakenly gates it
+# behind CLING_INCLUDE_TESTS: the previous EXISTS check on the bundled textinput
+# sources was dropped when those were removed in favor of LLVM's LineEditor, but the
+# subdirectory must still be added. See lib/UserInterface and tools/driver.
+add_subdirectory(UserInterface)
 add_subdirectory(Utils)