Call Tensor::alias() when returning an input Tensor (#1433)

* Call `Tensor::alias()` when concatenating a list of count 1

* multi_dot also

* broadcast_tensors

* Add release notes

Author: ds5678

RELEASENOTES.md

@@ -12,6 +12,7 @@ __API Changes__:
 
 #1374 Add accumulate to index_put_<br/>
 `torch.optim.lr_scheduler.PolynomialLR` `power` type has been corrected, is now double.<br/>
+Returning an input tensor has been corrected, is now `alias()`.<br/>
 
 # NuGet Version 0.105.0
 

src/TorchSharp/LinearAlgebra.cs

@@ -440,7 +440,7 @@ public static Tensor multi_dot(IList<Tensor> tensors)
                     throw new ArgumentException(nameof(tensors));
                 }
                 if (tensors.Count == 1) {
-                    return tensors[0];
+                    return tensors[0].alias();
                 }
 
                 using (var parray = new PinnedArray<IntPtr>()) {

src/TorchSharp/Tensor/torch.IndexingSlicingJoiningMutatingOps.cs

@@ -40,7 +40,7 @@ public static Tensor cat(IList<Tensor> tensors, long dim = 0)
             switch (tensors.Count)
             {
                 case <=0: throw new ArgumentException(nameof(tensors));
-                case 1: return tensors[0];
+                case 1: return tensors[0].alias();
             }
 
             using var parray = new PinnedArray<IntPtr>();

src/TorchSharp/Tensor/torch.OtherOperations.cs

@@ -63,7 +63,7 @@ public static IList<Tensor> broadcast_tensors(params Tensor[] tensors)
                 throw new ArgumentException(nameof(tensors));
             }
             if (tensors.Length == 1) {
-                return tensors;
+                return new Tensor[] { tensors[0].alias() };
             }
 
             IntPtr[] ptrArray;