Problem

After bumping the Eigen version we use, I noticed that they also define an operator^ for component-wise bitwise xor. On windows, this results in this compiler output: https://github.com/PhotonVision/thirdparty-gtsam/actions/runs/12537998515/job/34962683956

Resolutions:

For my uses, I can either patch Eigen to remove that operator, or patch GTSAM to remove its operator^ overloads. The code that added them is 10+ years old at this point it looks like (a54d177 4297d24 73fe5b2 ), and some of these might be exposed to downstream users? But the patch set to remove them is super tiny (attached below).
0001-Remove-Matrix-operator.patch
0002-Remove-SubgraphPreconditioner-operator.patch