diff --git a/include/asm-generic/Kbuild.asm b/include/asm-generic/Kbuild.asm
index 92a6d91..7cd25b8 100644
--- a/include/asm-generic/Kbuild.asm
+++ b/include/asm-generic/Kbuild.asm
@@ -1,6 +1,6 @@
 header-y  += kvm.h
 
-ifeq ($(wildcard include/asm-$(SRCARCH)/a.out.h),include/asm-$(SRCARCH)/a.out.h)
+ifneq ($(wildcard $(srctree)/include/asm-$(SRCARCH)/a.out.h),)
 unifdef-y += a.out.h
 endif
 unifdef-y += auxvec.h
diff --git a/include/asm-powerpc/Kbuild b/include/asm-powerpc/Kbuild
index 7381916..bca352e 100644
--- a/include/asm-powerpc/Kbuild
+++ b/include/asm-powerpc/Kbuild
@@ -1,6 +1,5 @@
 include include/asm-generic/Kbuild.asm
 
-header-y += a.out.h
 header-y += auxvec.h
 header-y += ioctls.h
 header-y += mman.h
diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index b6fbb25..71d70d1 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -166,7 +166,7 @@
 unifdef-y += adb.h
 unifdef-y += adfs_fs.h
 unifdef-y += agpgart.h
-ifeq ($(wildcard include/asm-$(SRCARCH)/a.out.h),include/asm-$(SRCARCH)/a.out.h)
+ifneq ($(wildcard $(srctree)/include/asm-$(SRCARCH)/a.out.h),)
 unifdef-y += a.out.h
 endif
 unifdef-y += apm_bios.h