diff --git a/Eigen/src/LU/FullPivLU.h b/Eigen/src/LU/FullPivLU.h
index 14a9c402d..dfe25f424 100644
--- a/Eigen/src/LU/FullPivLU.h
+++ b/Eigen/src/LU/FullPivLU.h
@@ -417,6 +417,9 @@ FullPivLU<MatrixType>::FullPivLU(const MatrixType& matrix)
 template<typename MatrixType>
 FullPivLU<MatrixType>& FullPivLU<MatrixType>::compute(const MatrixType& matrix)
 {
+  // the permutations are stored as int indices, so just to be sure:
+  eigen_assert(matrix.rows()<=NumTraits<int>::highest() && matrix.cols()<=NumTraits<int>::highest());
+  
   m_isInitialized = true;
   m_lu = matrix;
 
diff --git a/Eigen/src/LU/PartialPivLU.h b/Eigen/src/LU/PartialPivLU.h
index c9ff9dd5a..4017b5699 100644
--- a/Eigen/src/LU/PartialPivLU.h
+++ b/Eigen/src/LU/PartialPivLU.h
@@ -386,6 +386,9 @@ void partial_lu_inplace(MatrixType& lu, TranspositionType& row_transpositions, t
 template<typename MatrixType>
 PartialPivLU<MatrixType>& PartialPivLU<MatrixType>::compute(const MatrixType& matrix)
 {
+  // the row permutation is stored as int indices, so just to be sure:
+  eigen_assert(matrix.rows()<NumTraits<int>::highest());
+  
   m_lu = matrix;
 
   eigen_assert(matrix.rows() == matrix.cols() && "PartialPivLU is only for square (and moreover invertible) matrices");
diff --git a/Eigen/src/QR/ColPivHouseholderQR.h b/Eigen/src/QR/ColPivHouseholderQR.h
index 2cb255652..9ec8a65e4 100644
--- a/Eigen/src/QR/ColPivHouseholderQR.h
+++ b/Eigen/src/QR/ColPivHouseholderQR.h
@@ -401,6 +401,9 @@ ColPivHouseholderQR<MatrixType>& ColPivHouseholderQR<MatrixType>::compute(const
   Index rows = matrix.rows();
   Index cols = matrix.cols();
   Index size = matrix.diagonalSize();
+  
+  // the column permutation is stored as int indices, so just to be sure:
+  eigen_assert(cols<=NumTraits<int>::highest());
 
   m_qr = matrix;
   m_hCoeffs.resize(size);