diff --git a/scripts/dtc/Makefile b/scripts/dtc/Makefile
index e999be9..58d879d 100644
--- a/scripts/dtc/Makefile
+++ b/scripts/dtc/Makefile
@@ -9,21 +9,11 @@
 dtc-objs	+= dtc-lexer.lex.o dtc-parser.tab.o
 
 # Source files need to get at the userspace version of libfdt_env.h to compile
-
-HOSTCFLAGS_DTC := -I$(src) -I$(src)/libfdt
-
-HOSTCFLAGS_checks.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_data.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_dtc.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_flattree.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_fstree.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_livetree.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_srcpos.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_treesource.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_util.o := $(HOSTCFLAGS_DTC)
+HOST_EXTRACFLAGS := -I$(src)/libfdt
 
-HOSTCFLAGS_dtc-lexer.lex.o := $(HOSTCFLAGS_DTC)
-HOSTCFLAGS_dtc-parser.tab.o := $(HOSTCFLAGS_DTC)
+# Generated files need one more search path to include headers in source tree
+HOSTCFLAGS_dtc-lexer.lex.o := -I$(src)
+HOSTCFLAGS_dtc-parser.tab.o := -I$(src)
 
 # dependencies on generated files need to be listed explicitly
 $(obj)/dtc-lexer.lex.o: $(obj)/dtc-parser.tab.h