Using Index type instead of hard coded int type to prevent potential implicit integer conversion.

Eigen/src/SparseLU/SparseLU_kernel_bmod.h

diff --git a/Eigen/src/SparseLU/SparseLU_kernel_bmod.h b/Eigen/src/SparseLU/SparseLU_kernel_bmod.h
index 0d0283b..cad149d 100644
--- a/Eigen/src/SparseLU/SparseLU_kernel_bmod.h
+++ b/Eigen/src/SparseLU/SparseLU_kernel_bmod.h
@@ -31,13 +31,13 @@
 template <int SegSizeAtCompileTime> struct LU_kernel_bmod
 {
   template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
-  static EIGEN_DONT_INLINE void run(const int segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, Index& luptr, const Index lda,
+  static EIGEN_DONT_INLINE void run(const Index segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, Index& luptr, const Index lda,
                                     const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros);
 };
 
 template <int SegSizeAtCompileTime>
 template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
-EIGEN_DONT_INLINE void LU_kernel_bmod<SegSizeAtCompileTime>::run(const int segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, Index& luptr, const Index lda,
+EIGEN_DONT_INLINE void LU_kernel_bmod<SegSizeAtCompileTime>::run(const Index segsize, BlockScalarVector& dense, ScalarVector& tempv, ScalarVector& lusup, Index& luptr, const Index lda,
                                                                   const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros)
 {
   typedef typename ScalarVector::Scalar Scalar;
@@ -45,7 +45,7 @@
   // The result of triangular solve is in tempv[*]; 
     // The result of matric-vector update is in dense[*]
   Index isub = lptr + no_zeros; 
-  int i;
+  Index i;
   Index irow;
   for (i = 0; i < ((SegSizeAtCompileTime==Dynamic)?segsize:SegSizeAtCompileTime); i++)
   {
@@ -92,13 +92,13 @@
 template <> struct LU_kernel_bmod<1>
 {
   template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
-  static EIGEN_DONT_INLINE void run(const int /*segsize*/, BlockScalarVector& dense, ScalarVector& /*tempv*/, ScalarVector& lusup, Index& luptr,
+  static EIGEN_DONT_INLINE void run(const Index /*segsize*/, BlockScalarVector& dense, ScalarVector& /*tempv*/, ScalarVector& lusup, Index& luptr,
                                     const Index lda, const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros);
 };
 
 
 template <typename BlockScalarVector, typename ScalarVector, typename IndexVector, typename Index>
-EIGEN_DONT_INLINE void LU_kernel_bmod<1>::run(const int /*segsize*/, BlockScalarVector& dense, ScalarVector& /*tempv*/, ScalarVector& lusup, Index& luptr,
+EIGEN_DONT_INLINE void LU_kernel_bmod<1>::run(const Index /*segsize*/, BlockScalarVector& dense, ScalarVector& /*tempv*/, ScalarVector& lusup, Index& luptr,
                                               const Index lda, const Index nrow, IndexVector& lsub, const Index lptr, const Index no_zeros)
 {
   typedef typename ScalarVector::Scalar Scalar;