Subject: Re: ELF ABI query
To: David Laight <>
From: Richard Earnshaw <>
List: port-arm
Date: 11/30/2001 22:40:24
> Beware that certain versions of gcc with certain flag setting use
> misaligned accesses when reading 16-bit data items.....

The netbsd compiler will be configured to use a compilation mode which 
avoids unaligned accesses.  Support for this is already in the compiler, 
so it's just a matter of throwing a switch.

> I have also been told that some future ARM cpus might support
> misaligned transfers - but I don't know any details.

Having spoken to one of the ARM architects, I'm lead to believe that there 
are no plans at present to remove support for unaligned accesses, but this 
one thing that might be considered for removal at a later date.  Making 
use of this feature was always a bit of a kludge to work around the lack 
of 16-bit memory operations on the ARM, and the switch to ELF may be the 
only chance we get to remove the requirement to support it from NetBSD/ARM