diff --git a/sysdeps/unix/sysv/linux/arm/sys/io.h b/sysdeps/unix/sysv/linux/arm/sys/io.h
index 9f9eebc6fb..96d54cd337 100644
--- a/sysdeps/unix/sysv/linux/arm/sys/io.h
+++ b/sysdeps/unix/sysv/linux/arm/sys/io.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1996, 1998 Free Software Foundation, Inc.
+/* Copyright (C) 1996, 1998, 1999 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -26,22 +26,22 @@ __BEGIN_DECLS
 /* If TURN_ON is TRUE, request for permission to do direct i/o on the
    port numbers in the range [FROM,FROM+NUM-1].  Otherwise, turn I/O
    permission off for that range.  This call requires root privileges.  */
-extern int ioperm __P ((unsigned long int __from, unsigned long int __num,
-			int __turn_on));
+extern int ioperm (unsigned long int __from, unsigned long int __num,
+		   int __turn_on) __THROW;
 
 /* Set the I/O privilege level to LEVEL.  If LEVEL is nonzero,
    permission to access any I/O port is granted.  This call requires
    root privileges. */
-extern int iopl __P ((int __level));
+extern int iopl (int __level) __THROW;
 
 /* The functions that actually perform reads and writes.  */
-extern unsigned char inb (unsigned long port);
-extern unsigned short inw (unsigned long port);
-extern unsigned long inl (unsigned long port);
+extern unsigned char inb (unsigned long int port) __THROW;
+extern unsigned short int inw (unsigned long int port) __THROW;
+extern unsigned long int inl (unsigned long int port) __THROW;
 
-extern void outb (unsigned char value, unsigned long port);
-extern void outw (unsigned short value, unsigned long port);
-extern void outl (unsigned long value, unsigned long port);
+extern void outb (unsigned char value, unsigned long int port) __THROW;
+extern void outw (unsigned short value, unsigned long int port) __THROW;
+extern void outl (unsigned long value, unsigned long int port) __THROW;
 
 __END_DECLS