Re: [eigen] Problems compiling 3.0.2 tests on VS2008

[Jitse Niesen <jitse@xxxxxxxxxxxxxxxxx>]

On Sun, 11 Sep 2011, Benoit Jacob wrote:

> We should release 3.0.3 with this fix [for min/max macros], shouldn't 
> we?

Sounds like a good idea.

I tried compiling the Eigen2 tests and encountered failures in 
eigen2_alignedbox_1 and eigen2_alignedbox_2, in line 56, where it tests 
whether b2.contains(b1); all other tests pass. I tried to bisect and went 
back to the point that the Eigen2 tests were incorpored (pre-3.0.0), but 
the failure was still there (it's also present in the dev branch). So it 
doesn't really have to block a 3.0.3 release.

The test failures happen on a 32-bit Red Hat box with GCC 4.5.1 both with 
and without vectorization. I can reproduce them on a 64-bit Debian box 
with GCC 4.6.1 if I define EIGEN_TEST_X87.

The test in eigen2_alignedbox can be summarized as follows:

   AlignedBox<Vector2f> b1, b2;
   /* Initialize b1 and b2 */
   b2.extend(b1);
   VERIFY(b2.contains(b1));

So it basically is a test for floating-point equality, and my guess is 
that this fails due to the weird mix of double and extended precision with 
the x87 floating-point unit.


Jitse