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Date: Thu, 10 May 2012 11:49:09 -0500
From: Mark Hatle <mark.hatle@windriver.com>
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Subject: Re: Bad ARM code with GCC 4.7.1
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On 5/10/12 11:30 AM, Khem Raj wrote:
> On Thu, May 10, 2012 at 9:17 AM, Gary Thomas<gary@mlbassoc.com>  wrote:
>>
>> My board is DM3730, much like a BeagleBoard
>>   ARM architecture: armv7a
>>   Linux kernel 3.0
>
> hmmm that should be able to handle alignment faults in hardware

As far as I know, most armv7a handle alignment in the kernel, but there are 
newer crops of CPUs coming out that will no longer have alignment handlers as a 
"speed optimization".. (I think they're a bit nuts myself, but anyway.)

But if the code in question is inside the kernel, then the alignment faults 
won't work -- or will they?  (Certainly won't from within the alignment handlers 
of course...)

--Mark

>>
>>
>>>
>>> gcc generate unaligned accesses by default
>>>
>>> Does adding -mno-unaligned-access to cflags help ?
>>
>>
>> I'll check.
>
> Its not entirely clear whats going on so post the complete function disassembly
> so further context can be seen as well.
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