Why does normalizing a vector not work? Bug? [GetSafeNormal(), GetUnsafeNormal()]

This seems to be related to a compiler bug introduced in or around VS 2019 16.3.3 that MSFT is working to fix:
https://developercommunity.visualstudio.com/content/problem/734585/msvc-142328019-compilation-bug.html

They acknowledged the problem on 10/08/2019

There is a workaround solution(to use an older compiler version) in that link if you need to update your build immediately.

UPDATE:
Confirmed this was fixed in VS 2019 16.3.9