Add array variance checks

xtqqczze · Jun 18, 2021 · f261e92 · f261e92
1 parent a851f05
commit f261e92
Showing 1 changed file with 25 additions and 5 deletions.
diff --git a/src/libraries/System.Private.CoreLib/src/System/Array.cs b/src/libraries/System.Private.CoreLib/src/System/Array.cs
@@ -785,8 +785,18 @@ public static void Fill<T>(T[] array, T value)
                 ThrowHelper.ThrowArgumentNullException(ExceptionArgument.array);
             }
 
-            var span = new Span<T>(ref MemoryMarshal.GetArrayDataReference(array), array.Length);
-            span.Fill(value);
+            if (!typeof(T).IsValueType && array.GetType() != typeof(T[]))
+            {
+                for (int i = 0; i < array.Length; i++)
+                {
+                    array[i] = value;
+                }
+            }
+            else
+            {
+                var span = new Span<T>(ref MemoryMarshal.GetArrayDataReference(array), array.Length);
+                span.Fill(value);
+            }
         }
 
         public static void Fill<T>(T[] array, T value, int startIndex, int count)
@@ -806,9 +816,19 @@ public static void Fill<T>(T[] array, T value, int startIndex, int count)
                 ThrowHelper.ThrowCountArgumentOutOfRange_ArgumentOutOfRange_Count();
             }
 
-            ref T first = ref Unsafe.Add(ref MemoryMarshal.GetArrayDataReference(array), (nint)(uint)startIndex);
-            var span = new Span<T>(ref first, count);
-            span.Fill(value);
+            if (!typeof(T).IsValueType && array.GetType() != typeof(T[]))
+            {
+                for (int i = startIndex; i < startIndex + count; i++)
+                {
+                    array[i] = value;
+                }
+            }
+            else
+            {
+                ref T first = ref Unsafe.Add(ref MemoryMarshal.GetArrayDataReference(array), (nint)(uint)startIndex);
+                var span = new Span<T>(ref first, count);
+                span.Fill(value);
+            }
         }
 
         public static T? Find<T>(T[] array, Predicate<T> match)