diff --git a/examples/ntb/Makefile b/examples/ntb/Makefile
index 4675570fd2..d35dabc471 100644
--- a/examples/ntb/Makefile
+++ b/examples/ntb/Makefile
@@ -42,4 +42,4 @@ build:
 .PHONY: clean
 clean:
 	rm -f build/$(APP) build/$(APP)-static build/$(APP)-shared
-	rmdir --ignore-fail-on-non-empty build
+	test -d build && rmdir -p build || true