[eigen] Re: Eigen 3.3-rc2: no type named 'Traits' in 'Eigen::internal::g

On Mon, Nov 7, 2016 at 10:09 AM, Daniel Lee <bearlee@xxxxxxxxxxxx> wrote:

Hi all,

I've run into a new problem with Eigen 3.3-rc2. I'm guessing it's either a problem with how we've defined traits for the auto-diff types in Stan or it's a bug with not including the typedef (I saw something similar was patched a while ago).

Here's a short example that fails to compile:
// ex.cpp
#include <stan/math/rev/mat.hpp>

template <typename T>
Eigen::Matrix<T, -1, -1> foo(const Eigen::Matrix<T, -1, -1>& m) {
return m * m;
}

int main() {
Eigen::Matrix<stan::math::var, -1, -1> x(2, 2);
x << 1, 0, 0, 1;
foo(x);
return 0;
}

I'm using branch feature/0187-eigen-3.3 from https://github.com/stan-dev/math. To compile, I typed: clang++ ex.cpp -isystem lib/eigen_3.3-rc2 -isystem . -isystem lib/cvodes_2.9.0/include/
(I could simplify it further if that would help).

And here's the error message I get:

> clang++ ex.cpp -isystem lib/eigen_3.3-rc2 -isystem . -isystem lib/cvodes_2..9.0/include/
In file included from ex.cpp:1:
In file included from ./stan/math/rev/mat.hpp:4:
In file included from ./stan/math/rev/core.hpp:14:
In file included from ./stan/math/rev/core/matrix_vari.hpp:4:
In file included from ./stan/math/rev/mat/fun/Eigen_NumTraits.hpp:4:
In file included from ./stan/math/prim/mat/fun/Eigen.hpp:4:
In file included from lib/eigen_3.3-rc2/Eigen/Dense:1:
In file included from lib/eigen_3..3-rc2/Eigen/Core:480:
lib/eigen_3.3-rc2/Eigen/src/Core/products/GeneralMatrixMatrix.h:233:26: error: no type named 'Traits'
in 'Eigen::internal::general_matrix_matrix_product<long, stan::math::var, 0, false,
stan::math::var, 0, false, 0>'
typedef typename Gemm::Traits Traits;
~~~~~~~~~~~~~~~^~~~~~
lib/eigen_3.3-rc2/Eigen/src/Core/products/GeneralMatrixMatrix.h:484:10: note: in instantiation of
template class 'Eigen::internal::gemm_functor<stan::math::var, long,
Eigen::internal::general_matrix_matrix_product<long, stan::math::var, 0, false,
stan::math::var, 0, false, 0>, Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, Eigen::Matrix<stan::math::var, -1, -1, 0,
-1, -1>, Eigen::internal::gemm_blocking_space<0, stan::math::var, stan::math::var, -1, -1, -1,
1, false> >' requested here
(GemmFunctor(lhs, rhs, dst, actualAlpha, blocking), a_lhs.rows(), a_rhs.cols(), a_lhs...
^
lib/eigen_3.3-rc2/Eigen/src/Core/products/GeneralMatrixMatrix.h:435:7: note: in instantiation of
function template specialization
'Eigen::internal::generic_product_impl<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, Eigen::DenseShape, Eigen::DenseShape,
8>::scaleAndAddTo<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1> >' requested here
scaleAndAddTo(dst, lhs, rhs, Scalar(1));
^
lib/eigen_3.3-rc2/Eigen/src/Core/ProductEvaluators.h:148:37: note: in instantiation of function
template specialization 'Eigen::internal::generic_product_impl<Eigen::Matrix<stan::math::var,
-1, -1, 0, -1, -1>, Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, Eigen::DenseShape,
Eigen::DenseShape, 8>::evalTo<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1> >' requested
here
generic_product_impl<Lhs, Rhs>::evalTo(dst, src.lhs(), src.rhs());
^
lib/eigen_3.3-rc2/Eigen/src/Core/AssignEvaluator.h:814:46: note: in instantiation of member function
'Eigen::internal::Assignment<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Product<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, 0>,
Eigen::internal::assign_op<stan::math::var, stan::math::var>, Eigen::internal::Dense2Dense,
void>::run' requested here
Assignment<ActualDstTypeCleaned,Src,Func>::run(actualDst, src, func);
^
lib/eigen_3.3-rc2/Eigen/src/Core/PlainObjectBase.h:721:17: note: in instantiation of function
template specialization
'Eigen::internal::call_assignment_no_alias<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Product<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, 0>,
Eigen::internal::assign_op<stan::math::var, stan::math::var> >' requested here
internal::call_assignment_no_alias(this->derived(), other.derived(), internal::assign_o...
^
lib/eigen_3.3-rc2/Eigen/src/Core/PlainObjectBase.h:531:7: note: in instantiation of function template
specialization 'Eigen::PlainObjectBase<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>
>::_set_noalias<Eigen::Product<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, 0> >' requested here
_set_noalias(other);
^
lib/eigen_3.3-rc2/Eigen/src/Core/Matrix.h:379:9: note: in instantiation of function template
specialization 'Eigen::PlainObjectBase<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>
>::PlainObjectBase<Eigen::Product<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, 0> >' requested here
: Base(other.derived())
^
ex.cpp:5:10: note: in instantiation of function template specialization
'Eigen::Matrix<stan::math::var, -1, -1, 0, -1,
-1>::Matrix<Eigen::Product<Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>,
Eigen::Matrix<stan::math::var, -1, -1, 0, -1, -1>, 0> >' requested here
return m * m;
^
ex.cpp:11:3: note: in instantiation of function template specialization 'foo<stan::math::var>'
requested here
foo(x);
^
1 error generated.

Thank you.

Daniel

P.S. Is there a place with guidelines for writing traits correctly for 3.3? This code works for 3..2 and I haven't been able to find additional information on traits for custom types, especially with 3.3. If possible, we'd work through the guidelines to the best of our ability before hitting the list.