Add __EXPORTED_HEADERS__ as predefined macro.

To weed out stuff like this in uapi/linux/types.h

ifndef __EXPORTED_HEADERS__
warning "Attempt to use kernel headers from user space, see
http://kernelnewbies.org/KernelHeaders"
endif /* __EXPORTED_HEADERS__ */

Change-Id: I6506cea6248f7a3b44a839b98e91bdd0d3a6c4cd
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 3968605..f6486d7 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -34,6 +34,7 @@
     "__CHECKER__": kCppUndefinedMacro,
     "__CHECK_ENDIAN__": kCppUndefinedMacro,
     "CONFIG_X86_32": "__i386__",
+    "__EXPORTED_HEADERS__": "1",
     }
 
 # define to true if you want to remove all defined(CONFIG_FOO) tests
diff --git a/libc/kernel/uapi/linux/types.h b/libc/kernel/uapi/linux/types.h
index 3a3b381..4fdfe10 100644
--- a/libc/kernel/uapi/linux/types.h
+++ b/libc/kernel/uapi/linux/types.h
@@ -21,26 +21,23 @@
 #include <asm/types.h>
 #ifndef __ASSEMBLY__
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
-#ifndef __EXPORTED_HEADERS__
-#warning "Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders"
-#endif
 #include <linux/posix_types.h>
-/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define __bitwise__
 #define __bitwise
 typedef __u16 __bitwise __le16;
-typedef __u16 __bitwise __be16;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+typedef __u16 __bitwise __be16;
 typedef __u32 __bitwise __le32;
 typedef __u32 __bitwise __be32;
 typedef __u64 __bitwise __le64;
-typedef __u64 __bitwise __be64;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+typedef __u64 __bitwise __be64;
 typedef __u16 __bitwise __sum16;
 typedef __u32 __bitwise __wsum;
 #define __aligned_u64 __u64 __attribute__((aligned(8)))
-#define __aligned_be64 __be64 __attribute__((aligned(8)))
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+#define __aligned_be64 __be64 __attribute__((aligned(8)))
 #define __aligned_le64 __le64 __attribute__((aligned(8)))
 #endif
 #endif
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */