From owner-freebsd-hackers  Sat Mar 13 15: 5: 8 1999
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Date: Sat, 13 Mar 1999 15:09:06 -0800 (PST)
From: Chris Costello <chris@dei.calldei.com>
To: Dennis <dennis@etinc.com>
Cc: hackers@FreeBSD.ORG
Subject: Re: 'C' language question
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On Sat, 13 Mar 1999, Dennis wrote:

> 
> I have a memory mapped controller that requires that all of its
> register reads and writes be 32 bits....the follow code:
> 
> *reg |= 0x80000000;
> 
> generates a byte OR (ORB instruction) which trashes the register with
> gcc 2.9.2....a stupid "optimization" that happens to be wrong in this
> case.
> 
> is there a declaration that will force the compiler to generate a 32bit 
> OR (ORL instruction) on this?
> 

   Try using the 'asm { ... }' syntax in C. (of course, this is where your
code becomes platform-specific...)

> Dennis
> 
> 
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