fix bug #410: fix a possible out of range access in EigenSolver

2 files changed, 12 insertions, 1 deletions

diff --git a/Eigen/src/Eigenvalues/EigenSolver.h b/Eigen/src/Eigenvalues/EigenSolver.h
index 53b77385d..720a45bbc 100644
--- a/Eigen/src/Eigenvalues/EigenSolver.h
+++ b/Eigen/src/Eigenvalues/EigenSolver.h
@@ -339,7 +339,7 @@ typename EigenSolver<MatrixType>::EigenvectorsType EigenSolver<MatrixType>::eige
   EigenvectorsType matV(n,n);
   for (Index j=0; j<n; ++j)
   {
-    if (internal::isMuchSmallerThan(internal::imag(m_eivalues.coeff(j)), internal::real(m_eivalues.coeff(j))))
+    if (internal::isMuchSmallerThan(internal::imag(m_eivalues.coeff(j)), internal::real(m_eivalues.coeff(j))) || j+1==n)
     {
       // we have a real eigen value
       matV.col(j) = m_eivec.col(j).template cast<ComplexScalar>();
diff --git a/test/eigensolver_generic.cpp b/test/eigensolver_generic.cpp
index 96ff4f873..2e9cdc7a5 100644
--- a/test/eigensolver_generic.cpp
+++ b/test/eigensolver_generic.cpp
@@ -114,6 +114,17 @@ void test_eigensolver_generic()
 
   // Test problem size constructors
   CALL_SUBTEST_5(EigenSolver<MatrixXf>(s));
+
+  // regression test for bug 410
+  CALL_SUBTEST_2(
+  {
+     MatrixXd A(1,1);
+     A(0,0) = std::sqrt(-1.);
+     Eigen::EigenSolver<MatrixXd> solver(A);
+     MatrixXd V(1, 1);
+     V(0,0) = solver.eigenvectors()(0,0).real();
+  }
+  );
   
   EIGEN_UNUSED_VARIABLE(s)
 }