diff --git a/include/linux/reboot.h b/include/linux/reboot.h
index 988e55f..3005d5a 100644
--- a/include/linux/reboot.h
+++ b/include/linux/reboot.h
@@ -64,6 +64,7 @@ extern void kernel_restart(char *cmd);
 extern void kernel_halt(void);
 extern void kernel_power_off(void);
 
+extern int C_A_D; /* for sysctl */
 void ctrl_alt_del(void);
 
 #define POWEROFF_CMD_PATH_LEN	256
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 0ef19c6..72c3b1e 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -65,7 +65,6 @@
 #if defined(CONFIG_SYSCTL)
 
 /* External variables not in a header file. */
-extern int C_A_D;
 extern int print_fatal_signals;
 extern int sysctl_overcommit_memory;
 extern int sysctl_overcommit_ratio;