diff --git a/test/Makefile b/test/Makefile
index f5e9ff52bfc..9ddfabfb9a8 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -62,6 +62,15 @@ clang-site-cfg: FORCE
 	$(MAKE) -C $(PROJ_OBJ_DIR)/../tools/clang/test lit.site.cfg Unit/lit.site.cfg
 extra-site-cfgs:: clang-site-cfg
 endif
+
+ifeq ($(shell test -f $(PROJ_OBJ_DIR)/../tools/clang/tools/extra/Makefile && echo OK), OK)
+LIT_ALL_TESTSUITES += $(PROJ_OBJ_DIR)/../tools/clang/tools/extra/test
+
+# Force creation of Clang Tools' lit.site.cfg.
+clang-tools-site-cfg: FORCE
+	$(MAKE) -C $(PROJ_OBJ_DIR)/../tools/clang/tools/extra/test lit.site.cfg
+extra-site-cfgs:: clang-tools-site-cfg
+endif
 endif
 endif