diff --git a/test/Makefile b/test/Makefile
index bd6b672dd3d..b47695100a9 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -60,6 +60,11 @@ 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