[eigen] Assignment of product to X.noalias() does not resize X

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What is the reason behind the following inconsistency (using the current revision of the development branch)?

#include <Eigen/Core>
#include <Eigen/Array>

using namespace Eigen;

int main()
  MatrixXf A = MatrixXf::Random(12,12);
  MatrixXf A2;
  A2 = A * A;			// works
  std::cout << A2(1,1) << std::endl;
  MatrixXf A3(12,12);
  A3.noalias() = A * A;		// works
  std::cout << A3(1,1) << std::endl;
  MatrixXf A4;
  A4.noalias() = A * A;		// does NOT work
  std::cout << A4(1,1) << std::endl;

The assignment to A4 complains (via a run-time assertion) that A4 has the wrong dimension. Yet when we leave out the noalias(), as in the assignment to A2, it does resize the matrix to the correct dimension.

In the 2.0 branch, A4 = (A * A).lazy() does resize the matrix A4.


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