Always include <sys/cdefs.h> first.

Otherwise you can't be sure that things like __BIONIC__ work.

Change-Id: Ic5e59988b69419828c3b1a97332c7e2ab58e09a1
diff --git a/libc/include/bits/bionic_multibyte_result.h b/libc/include/bits/bionic_multibyte_result.h
index 0d5cf21..930e67c 100644
--- a/libc/include/bits/bionic_multibyte_result.h
+++ b/libc/include/bits/bionic_multibyte_result.h
@@ -34,9 +34,10 @@
  * conversion APIs defined by C.
  */
 
-#include <stddef.h>
 #include <sys/cdefs.h>
 
+#include <stddef.h>
+
 __BEGIN_DECLS
 
 /**
diff --git a/libc/include/bits/seek_constants.h b/libc/include/bits/seek_constants.h
index bfc02a8..a4fffb2 100644
--- a/libc/include/bits/seek_constants.h
+++ b/libc/include/bits/seek_constants.h
@@ -33,6 +33,8 @@
  * @brief The `SEEK_` constants.
  */
 
+#include <sys/cdefs.h>
+
 /** Seek to an absolute offset. */
 #define SEEK_SET 0
 /** Seek relative to the current offset. */
diff --git a/libc/include/bits/swab.h b/libc/include/bits/swab.h
index 9591c2e..da2865a 100644
--- a/libc/include/bits/swab.h
+++ b/libc/include/bits/swab.h
@@ -28,8 +28,9 @@
 
 #pragma once
 
-#include <stdint.h>
 #include <sys/cdefs.h>
+
+#include <stdint.h>
 #include <sys/types.h>
 
 #if !defined(__BIONIC_SWAB_INLINE)
diff --git a/libc/include/bits/termios_inlines.h b/libc/include/bits/termios_inlines.h
index a884b59..bb04e4d 100644
--- a/libc/include/bits/termios_inlines.h
+++ b/libc/include/bits/termios_inlines.h
@@ -29,8 +29,9 @@
 #ifndef _BITS_TERMIOS_INLINES_H_
 #define _BITS_TERMIOS_INLINES_H_
 
-#include <errno.h>
 #include <sys/cdefs.h>
+
+#include <errno.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 
diff --git a/libc/include/bits/termios_winsize_inlines.h b/libc/include/bits/termios_winsize_inlines.h
index ae246e4..86777b0 100644
--- a/libc/include/bits/termios_winsize_inlines.h
+++ b/libc/include/bits/termios_winsize_inlines.h
@@ -28,8 +28,9 @@
 
 #pragma once
 
-#include <errno.h>
 #include <sys/cdefs.h>
+
+#include <errno.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 
diff --git a/libc/include/bits/threads_inlines.h b/libc/include/bits/threads_inlines.h
index 05b785a..ab294c1 100644
--- a/libc/include/bits/threads_inlines.h
+++ b/libc/include/bits/threads_inlines.h
@@ -28,6 +28,8 @@
 
 #pragma once
 
+#include <sys/cdefs.h>
+
 #include <threads.h>
 
 #include <errno.h>