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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] About Complex numbers Todo
- From: Bastien ROUCARIES <roucaries.bastien@xxxxxxxxx>
- Date: Fri, 20 Aug 2010 11:09:08 +0200
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On Fri, Aug 20, 2010 at 10:41 AM, Carlos Becker <carlosbecker@xxxxxxxxx> wrote:
> Hi Bastien. If I get things right then there might be two issues with this:
> first it is only for C++0x, so older C++ versions would not be supported.
In theory yes, but in pratice no. All the major compiler team are part
of the standard board. And if g++ does not support this we could open
soon a bug report.
> Furthermore, and if I remember correctly, complex numbers are stored in
> memory as an array, even though it might be hidden by a struct or class.
That is the point. At least it "array[2] storage layout which makes
many optimizations unsafe" is not true because standard board has
agree since 2004 that the next standard will use implicitlty this
layout. So the layout is guaranted by pratice (see the remark in the
standard rationnale) in the current state of standard and officially
for the next standard.
And BTW c++ user should use recent compiler see for instance the bug :
http://gcc.gnu.org/viewcvs?view=revision&revision=156874
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43108
Bastien