diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 5e7255d..a2dbbd8 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -161,7 +161,7 @@
 # Prefix -I with $(srctree) if it is not an absolute path.
 # skip if -I has no parameter
 addtree = $(if $(patsubst -I%,%,$(1)), \
-$(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))
+$(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1),$(1))
 
 # Find all -I options and call addtree
 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))