Revert "BDCSVD fix -Wmaybe-uninitialized"

This reverts merge request !1649
diff --git a/Eigen/src/SVD/BDCSVD.h b/Eigen/src/SVD/BDCSVD.h
index a49299c..192f42f 100644
--- a/Eigen/src/SVD/BDCSVD.h
+++ b/Eigen/src/SVD/BDCSVD.h
@@ -52,8 +52,9 @@
 
 template <typename MatrixType, int Options>
 struct allocate_small_svd {
-  static void run(JacobiSVD<MatrixType, Options>& smallSvd, Index rows, Index cols, unsigned int) {
-    internal::construct_at(&smallSvd, rows, cols);
+  static void run(JacobiSVD<MatrixType, Options>& smallSvd, Index rows, Index cols, unsigned int computationOptions) {
+    (void)computationOptions;
+    smallSvd = JacobiSVD<MatrixType, Options>(rows, cols);
   }
 };
 
@@ -63,7 +64,7 @@
 template <typename MatrixType>
 struct allocate_small_svd<MatrixType, 0> {
   static void run(JacobiSVD<MatrixType>& smallSvd, Index rows, Index cols, unsigned int computationOptions) {
-    internal::construct_at(&smallSvd, rows, cols, computationOptions);
+    smallSvd = JacobiSVD<MatrixType>(rows, cols, computationOptions);
   }
 };
 
diff --git a/Eigen/src/SVD/JacobiSVD.h b/Eigen/src/SVD/JacobiSVD.h
index 84934db..615aad1 100644
--- a/Eigen/src/SVD/JacobiSVD.h
+++ b/Eigen/src/SVD/JacobiSVD.h
@@ -553,8 +553,7 @@
    * \deprecated Will be removed in the next major Eigen version. Options should
    * be specified in the \a Options template parameter.
    */
-  // EIGEN_DEPRECATED // this constructor is used to allocate memory in BDCSVD
-  JacobiSVD(Index rows, Index cols, unsigned int computationOptions) {
+  EIGEN_DEPRECATED JacobiSVD(Index rows, Index cols, unsigned int computationOptions) {
     internal::check_svd_options_assertions<MatrixType, Options>(computationOptions, rows, cols);
     allocate(rows, cols, computationOptions);
   }