diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 776842b..be38198 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -513,7 +513,7 @@
 
 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
 
-ifneq ($(srctree),.)
+ifdef building_out_of_srctree
 # Create directories for object files if they do not exist
 obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets))))
 # If targets exist, their directories apparently exist. Skip mkdir.