From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexander Holler <holler@ahsoftware.de>
Date: Sat, 22 Jan 2011 13:46:19 +0100
Subject: [U-Boot] WARNING: in gcc 4.5.0 and 4.5.1 volatile is ignored
Message-ID: <4D3AD19B.6030102@ahsoftware.de>
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To: u-boot@lists.denx.de

Hello,

because I've recently seen some other places where volatile is used to 
access registers without using read?() or write?() and many people seem 
to start using 4.5.1, I want to post this warning using a descriptive 
subject.

The keyword volatile might not have any effect when reading when gcc 
4.5.0 or 4.5.1 is used.

The appropriate bug seems to be that one:

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45052

You might either change such code to use readb(), readw() or readl(), or 
you have to use either an older version of gcc or a version >= 4.5.2 (it 
is fixed in 4.5.2).

A patch for write?() and read?() is currently in the 
u-boot-arm-repository (but not in the master and not in 2010.12):

http://lists.denx.de/pipermail/u-boot/2011-January/084885.html

Regards,

Alexander