diff --git a/libc/kernel/arch-x86/asm/a.out.h b/libc/kernel/arch-x86/asm/a.out.h
index 6aecff7..fa287b5 100644
--- a/libc/kernel/arch-x86/asm/a.out.h
+++ b/libc/kernel/arch-x86/asm/a.out.h
@@ -7,25 +7,33 @@
  ***   structures, and macros generated from the original header, and thus,
  ***   contains no copyrightable information.
  ***
+ ***   To edit the content of this header, modify the corresponding
+ ***   source file (e.g. under external/kernel-headers/original/) then
+ ***   run bionic/libc/kernel/tools/update_all.py
+ ***
+ ***   Any manual change here will be lost the next time this script will
+ ***   be run. You've been warned!
+ ***
  ****************************************************************************
  ****************************************************************************/
 #ifndef _ASM_X86_A_OUT_H
 #define _ASM_X86_A_OUT_H
-
 struct exec
 {
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
  unsigned int a_info;
  unsigned a_text;
  unsigned a_data;
  unsigned a_bss;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
  unsigned a_syms;
  unsigned a_entry;
  unsigned a_trsize;
  unsigned a_drsize;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 };
-
 #define N_TRSIZE(a) ((a).a_trsize)
 #define N_DRSIZE(a) ((a).a_drsize)
 #define N_SYMSIZE(a) ((a).a_syms)
-
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #endif