Merge branch 'stable_forced_align' into forced_align_backptr

Author: samanklesaria

src/libtorchaudio/forced_align/cpu/compute.cpp

@@ -27,7 +27,7 @@ void forced_align_impl(
   const auto L = targets.size(1);
   const auto S = 2 * L + 1;
 
-  auto alphas_a = new scalar_t[S][2];
+  auto alphas_a = new scalar_t[S][2]; // scalar_t is just logProbs.dtype()
   for (int i = 0; i < S; i++) {
     alphas_a[i][0] = kNegInfinity;
     alphas_a[i][1] = kNegInfinity;
@@ -122,6 +122,7 @@ void forced_align_impl(
   }
   auto idx1 = (T - 1) % 2;
   auto ltrIdx = alphas_a[S - 1][idx1] > alphas_a[S - 2][idx1] ? S - 1 : S - 2;
+  delete[] alphas_a;
   // path stores the token index for each time step after force alignment.
   for (auto t = T - 1; t > -1; t--) {
     auto lbl_idx = ltrIdx % 2 == 0 ? blank : targets_a[batchIndex][ltrIdx / 2];