From owner-freebsd-hackers  Sat Mar 13 14:28:40 1999
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Date: Sat, 13 Mar 1999 17:41:04 -0500
To: hackers@freebsd.org
From: Dennis <dennis@etinc.com>
Subject: 'C' language question
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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?

Dennis


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