diff --git a/wumsloader/Makefile b/wumsloader/Makefile
index 91dcb1d..4e5025b 100644
--- a/wumsloader/Makefile
+++ b/wumsloader/Makefile
@@ -126,7 +126,7 @@ export OUTPUT	:=	$(CURDIR)/$(TARGET)
 
 #---------------------------------------------------------------------------------
 $(BUILD):
-	@[ -d $@ ] || mkdir -p $@
+	@$(shell [ ! -d $(BUILD) ] && mkdir -p $(BUILD))
 	@$(MAKE) --no-print-directory -C $(BUILD) -f $(CURDIR)/Makefile