[Ipopt] C++ version of Ipopt is much slower than Fortran version of Ipopt ?

[Ali Baharev]

Interesting remark.

It may be an algorithmic difference rather than compilation issue, and
probably more test problems from various fields should be involved.

https://projects.coin-or.org/Ipopt/wiki/FAQ
What is the difference between the Fortran version and the C++ version?
[...]
Currently, there are some features in the Fortran version that are not
implemented in the C++ version.

Is the increase in time due to increased (average) time per iteration
or increased number of iteration or both?

Which optimization flags did you use?

Best,

Ali