| Re: [eigen] glibc's malloc (x86-64) 16 byte aligned? |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] glibc's malloc (x86-64) 16 byte aligned?
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Mon, 25 Jan 2010 12:58:16 -0500
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oh!
i didn't read correctly - "(or sixteen on 64-bit systems)"
I think that's an error on their part. Here on linux x86-64 that's
definitely not the case.
Benoit
2010/1/25 Benoit Jacob <jacob.benoit.1@xxxxxxxxx>:
> I don't understand?
> on linux x86-64, malloc only returns 8-byte aligned pointers, and this
> page confirms it.
> Benoit
>
> 2010/1/25 Rohit Garg <rpg.314@xxxxxxxxx>:
>> Hi all,
>>
>> http://www.gnu.org/s/libc/manual/html_node/Aligned-Memory-Blocks.html
>>
>> I was quite surprised to come across this. I never knew this was the
>> case. I wrote a quick, dirty, non-comprehensive, non-exhaustive test
>> and all of the malloc'ed pointers were 16 byte aligned.
>>
>> May be it's worth trying to run the eigen's test suite on linux x86-64
>> assuming that the malloc is 16 byte aligned?
>>
>> Your thoughts?
>>
>> --
>> Rohit Garg
>>
>> http://rpg-314.blogspot.com/
>>
>> Senior Undergraduate
>> Department of Physics
>> Indian Institute of Technology
>> Bombay
>>
>>
>>
>