Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!inuxc!iuvax!bsu-cs!dhesi
From: dhesi@bsu-cs.UUCP (Rahul Dhesi)
Newsgroups: comp.lang.c
Subject: Re: comma operator
Message-ID: <1934@bsu-cs.UUCP>
Date: 23 Jan 88 20:14:46 GMT
References: <3819@sigi.Colorado.EDU> <8599@ism780c.UUCP> <1866@bsu-cs.UUCP> <4037@june.cs.washington.edu> <10293@mimsy.UUCP>
Reply-To: dhesi@bsu-cs.UUCP (Rahul Dhesi)
Organization: CS Dept, Ball St U, Muncie, Indiana
Lines: 21

In article <10293@mimsy.UUCP> chris@mimsy.UUCP (Chris Torek) writes:
>The *only* way to guarantee proper operation
>under dpANS rules is to write
>
>	volatile int *ctlr_p = DISK_CTRL_REGISTER;
>	volatile int *out_p = DISK_OUT_REGISTER;

Or, for the sake of argument and abandoning all hope of efficiency, one
could say:

     extern unsigned *read_disk_ctrl_register (void);
     extern void write_disk_ctrl_register (unsigned);

If compiled separately, and until globally optimizng *linkers* are
developed, even a globally optimizing compiler really has no choice but
to respect an order such as:

     write_disk_ctrl_register (RESET);		/* must be done first */
     status = read_disk_ctrl_register ();	/* must be done second */
-- 
Rahul Dhesi         UUCP:  <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!dhesi