FPE: FLTINV and FLTDIV in Eigen::Spline interpolation

[paulgessinger]

 0# Eigen::internal::triangular_solve_matrix<double, long, 1, 2, false, 0, 0, 1>::run(long, long, double const*, long, double*, long, long, Eigen::internal::level3_blocking<double, double>&) at /builds/acts/ci-bridge/dependencies/view/include/eigen3/Eigen/src/Core/products/TriangularSolverMatrix.h:124
 1# void Eigen::HouseholderQR<Eigen::Matrix<double, -1, -1, 0, -1, -1> >::_solve_impl<Eigen::Matrix<double, -1, -1, 0, -1, -1>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::Matrix<double, -1, -1, 0, -1, -1> const&, Eigen::Matrix<double, -1, -1, 0, -1, -1>&) const at /builds/acts/ci-bridge/dependencies/view/include/eigen3/Eigen/src/QR/HouseholderQR.h:371
 2# void Eigen::internal::call_dense_assignment_loop<Eigen::Array<double, 3, -1, 0, 3, -1>, Eigen::Transpose<Eigen::Solve<Eigen::HouseholderQR<Eigen::Matrix<double, -1, -1, 0, -1, -1> >, Eigen::Matrix<double, -1, -1, 0, -1, -1> > const>, Eigen::internal::assign_op<double, double> >(Eigen::Array<double, 3, -1, 0, 3, -1>&, Eigen::Transpose<Eigen::Solve<Eigen::HouseholderQR<Eigen::Matrix<double, -1, -1, 0, -1, -1> >, Eigen::Matrix<double, -1, -1, 0, -1, -1> > const> const&, Eigen::internal::assign_op<double, double> const&) at /builds/acts/ci-bridge/dependencies/view/include/eigen3/Eigen/src/Core/AssignEvaluator.h:778
 3# Eigen::Spline<double, 3, -1> Eigen::SplineFitting<Eigen::Spline<double, 3, -1> >::Interpolate<Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::Matrix<double, -1, -1, 0, -1, -1> const&, long, Eigen::Array<double, 1, -1, 1, 1, -1> const&) at /builds/acts/ci-bridge/dependencies/view/include/eigen3/unsupported/Eigen/src/Splines/SplineFitting.h:315
 4# std::vector<Eigen::Matrix<double, 4, 1, 0, 4, 1>, std::allocator<Eigen::Matrix<double, 4, 1, 0, 4, 1> > > Acts::Interpolation3D::spline<std::vector<Eigen::Matrix<double, 4, 1, 0, 4, 1>, std::allocator<Eigen::Matrix<double, 4, 1, 0, 4, 1> > > >(std::vector<Eigen::Matrix<double, 4, 1, 0, 4, 1>, std::allocator<Eigen::Matrix<double, 4, 1, 0, 4, 1> > > const&, unsigned long, bool) at /builds/acts/ci-bridge/src/Core/include/Acts/Visualization/Interpolation3D.hpp:62
 5# ActsExamples::ObjSimHitWriter::writeT(ActsExamples::AlgorithmContext const&, boost::container::flat_multiset<ActsFatras::Hit, ActsExamples::detail::CompareGeometryId, void> const&) at /builds/acts/ci-bridge/src/Examples/Io/Obj/src/ObjSimHitWriter.cpp:125
 6# ActsExamples::Sequencer::run()::{lambda()#1}::operator()() const::{lambda(tbb::detail::d1::blocked_range<unsigned long> const&)#1}::operator()(tbb::detail::d1::blocked_range<unsigned long> const&) const at /builds/acts/ci-bridge/src/Examples/Framework/src/Framework/Sequencer.cpp:502
 7# ActsExamples::Sequencer::run()::{lambda()#1}::operator()() const at /builds/acts/ci-bridge/src/Examples/Framework/src/Framework/Sequencer.cpp:463

@asalzburger could you look into this one?

[asalzburger]

Interesting, where does this come from?

[paulgessinger]

I noticed this with the Spack build (maybe newer Eigen version?) in the test_full_chain_odd_example_pythia_geant4 test, which schedules the OBJ writing. I'm guessing it's some numerical edge case?