Eigen3 was introduced in:
SHA: 99b11184c89a15ec50daf1086d720c63fd33d2b0
InsightSoftwareConsortium/ITK@99b1118
Date: 2018-11-18
In this issue, microsoft/vcpkg#5115 (comment), we were pointed into VS inefficient code with Eigen3
So a benchmark using the VS compiler between: 99b11184c89a15ec50daf1086d720c63fd33d2b0^ (just before that commit) and after would be great.