RE: [eigen] question on alignment

[Basil Fierz <basil.fierz@xxxxxxxxxxx>]

Note that we run into the same issue as soon as we start using AVX with
MSVC.
I once tried some "simple" things an ran into alignment issue, however, I
did not have time to look into it.
SSE's alignment is the default for 64bit with MSVC (16 bytes). AVX needs a
32 byte alignment.

Best,
Basil

-----Original Message-----
From: Hauke Heibel [mailto:hauke.heibel@xxxxxxxxx] 
Sent: Mittwoch, 10. Oktober 2012 13:16
To: eigen@xxxxxxxxxxxxxxxxxxx
Subject: Re: [eigen] question on alignment

On Wed, Oct 10, 2012 at 11:37 AM, Sylvain Pointeau
<sylvain.pointeau@xxxxxxxxx> wrote:
> Is it happening to everybody to end up with all classes having 
> EIGEN_MAKE_ALIGNED_OPERATOR_NEW?

There exist exceptions but they come at a price. You will most likely loose
portability.

I am e.g. developing solely with VC compilers and only in 64bit mode - this
is one of those rare and special cases where I know that everything is
properly aligned and I do not need to use EIGEN_MAKE_ALIGNED_OPERATOR_NEW
nor Eigen::aligned_allocator. I guess you can imagine the issues I would be
facing when I wanted to go back to 32bit code, or maybe simply switch to
another compiler which does not ensure this alignment.

Regards,
Hauke