I am writing an application that makes heavy use of both OpenMP and Eigen, but I want to turn off Eigen's use of OpenMP. Is there a flag that I can use when building my application to do this?

Thanks for the input!

you can define EIGEN_DONT_PARALLELIZE

You can also control Eigen at runtime using:

Eigen::setNbThreads(n)

Perfect, exactly what I was looking for. Thank you!