diff --git a/arch/ia64/sn/kernel/Makefile b/arch/ia64/sn/kernel/Makefile
index 0a59371d347583122b4a5677680f5c88bdfdfc1d..688a3c27e0f6270b10c335bbc316958598ada78a 100644
--- a/arch/ia64/sn/kernel/Makefile
+++ b/arch/ia64/sn/kernel/Makefile
@@ -7,7 +7,7 @@
 # Copyright (C) 1999,2001-2006 Silicon Graphics, Inc.  All Rights Reserved.
 #
 
-CPPFLAGS += -I$(srctree)/arch/ia64/sn/include
+EXTRA_CFLAGS += -Iarch/ia64/sn/include
 
 obj-y				+= setup.o bte.o bte_error.o irq.o mca.o idle.o \
 				   huberror.o io_acpi_init.o io_common.o \
diff --git a/arch/ia64/sn/kernel/sn2/Makefile b/arch/ia64/sn/kernel/sn2/Makefile
index 99e1776932347937745c0fafbb3ed7ad9fdb5ace..08e6565dc908d0b0f5e8358a14698211439bb1c0 100644
--- a/arch/ia64/sn/kernel/sn2/Makefile
+++ b/arch/ia64/sn/kernel/sn2/Makefile
@@ -9,7 +9,7 @@
 # sn2 specific kernel files
 #
 
-CPPFLAGS += -I$(srctree)/arch/ia64/sn/include
+EXTRA_CFLAGS += -Iarch/ia64/sn/include
 
 obj-y += cache.o io.o ptc_deadlock.o sn2_smp.o sn_proc_fs.o \
 	 prominfo_proc.o timer.o timer_interrupt.o sn_hwperf.o
diff --git a/arch/ia64/sn/pci/Makefile b/arch/ia64/sn/pci/Makefile
index c6946784a6a81aaae694ea84513c3ff6770d2aad..ad4ef34dfe263cd66b496c445fd26e61246d02b7 100644
--- a/arch/ia64/sn/pci/Makefile
+++ b/arch/ia64/sn/pci/Makefile
@@ -7,6 +7,6 @@
 #
 # Makefile for the sn pci general routines.
 
-CPPFLAGS += -I$(srctree)/arch/ia64/sn/include
+EXTRA_CFLAGS += -Iarch/ia64/sn/include
 
 obj-y := pci_dma.o tioca_provider.o tioce_provider.o pcibr/
diff --git a/arch/ia64/sn/pci/pcibr/Makefile b/arch/ia64/sn/pci/pcibr/Makefile
index 3b403ea456f9264292da6961d3213dc0f51d0659..01192d3247ddef19b1388cf39be80c03e3ee6d88 100644
--- a/arch/ia64/sn/pci/pcibr/Makefile
+++ b/arch/ia64/sn/pci/pcibr/Makefile
@@ -7,7 +7,7 @@
 #
 # Makefile for the sn2 io routines.
 
-CPPFLAGS += -I$(srctree)/arch/ia64/sn/include
+EXTRA_CFLAGS += -Iarch/ia64/sn/include
 
 obj-y				+=  pcibr_dma.o pcibr_reg.o \
 				    pcibr_ate.o pcibr_provider.o