diff --git a/Makefile b/Makefile
index 278d50992c71642a09c04ef2475f2a63585d62a9..2717223d8666b1c2001427d6ffd2004bea8de488 100644
--- a/Makefile
+++ b/Makefile
@@ -1149,7 +1149,7 @@ endif # KBUILD_EXTMOD
 #(which is the most common case IMHO) to avoid unneeded clutter in the big tags file.
 #Adding $(srctree) adds about 20M on i386 to the size of the output file!
 
-ifeq ($(KBUILD_OUTPUT),)
+ifeq ($(src),$(obj))
 __srctree =
 else
 __srctree = $(srctree)/