Hi all,

I've been working with Eigen for about 3 months now and I've run into trouble lately. I've several projects on my VS solution, and one of them takes a really long time to compile (40+ mins). I've located the code sections that cause this long compilation times when using O2 optimization and the only relevant aspect I can see is that they make intensive use of Matrix33 and Vector3 classes. I'd like to know if anybody has dealt with this problem before or if this is a known issue and there is no real solution...

Just to summarize, with O2 optimization compilation times are 40+ mins, while without optimization it's about 2 mins. Of course, without the optimization execution is REALLY slow.

Thanks in advance.

I am seeing these compile time issues as well and so far I have no idea where they come from. I tried to do some analysis but somehow I ran out of time and I am still lacking time to investigate this further at the moment.

There is an incredible set of articles over here http://gameangst.com/?p=46 which is providing in depth discussion on how to analyze and improve compile times. Besides other things it is also discussing problems such as "template overspecialization" and the articles are most likely interesting to quite a few people and not solely MSVC related.

But again, right now I don't have the time to investigate the issue in detail...

Regards
Hauke

On the site of the pcl lib there is also an article about compilation times.
Not especially related to Eigen (but pcl uses Eigen).
http://www.ros.org/wiki/pcl/Compiling/