Fix compiler warnings

Author: Martin-Molinero

Directory.Build.props

@@ -4,7 +4,6 @@
     <AssemblyCopyright>Copyright (c) 2006-2021 The Contributors of the Python.NET Project</AssemblyCopyright>
     <AssemblyCompany>pythonnet</AssemblyCompany>
     <AssemblyProduct>Python.NET</AssemblyProduct>
-    <LangVersion>10.0</LangVersion>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 </Project>

src/embed_tests/StateSerialization/MethodSerialization.cs

@@ -1,4 +1,4 @@
-using System.IO;
+/*using System.IO;
 using System.Reflection;
 
 using NUnit.Framework;
@@ -44,3 +44,4 @@ public class MethodTestHost
     public MethodTestHost(int _) { }
     public void Generic<T>(T item, T[] array, ref T @ref) { }
 }
+*/

src/runtime/MethodBinder.cs

@@ -793,7 +793,6 @@ internal Binding Bind(BorrowedReference inst, BorrowedReference args, BorrowedRe
 
         static BorrowedReference HandleParamsArray(BorrowedReference args, int arrayStart, int pyArgCount, out NewReference tempObject)
         {
-            BorrowedReference op;
             tempObject = default;
             // for a params method, we may have a sequence or single/multiple items
             // here we look to see if the item at the paramIndex is there or not
@@ -806,20 +805,19 @@ static BorrowedReference HandleParamsArray(BorrowedReference args, int arrayStar
                 if (!Runtime.PyString_Check(item) && (Runtime.PySequence_Check(item) || (ManagedType.GetManagedObject(item) as CLRObject)?.inst is IEnumerable))
                 {
                     // it's a sequence (and not a string), so we use it as the op
-                    op = item;
+                    return item;
                 }
                 else
                 {
                     tempObject = Runtime.PyTuple_GetSlice(args, arrayStart, pyArgCount);
-                    op = tempObject.Borrow();
+                    return tempObject.Borrow();
                 }
             }
             else
             {
                 tempObject = Runtime.PyTuple_GetSlice(args, arrayStart, pyArgCount);
-                op = tempObject.Borrow();
+                return tempObject.Borrow();
             }
-            return op;
         }
 
         /// <summary>

src/runtime/Native/NewReference.cs

@@ -15,7 +15,7 @@ ref struct NewReference
 
         /// <summary>Creates a <see cref="NewReference"/> pointing to the same object</summary>
         [DebuggerHidden]
-        public NewReference(BorrowedReference reference, bool canBeNull = false)
+        public NewReference(scoped BorrowedReference reference, bool canBeNull = false)
         {
             var address = canBeNull
                 ? reference.DangerousGetAddressOrNull()
@@ -157,15 +157,15 @@ public static bool IsNull(this in NewReference reference)
 
         [Pure]
         [DebuggerHidden]
-        public static BorrowedReference BorrowNullable(this in NewReference reference)
+        public static BorrowedReference BorrowNullable(this scoped in NewReference reference)
             => new(NewReference.DangerousGetAddressOrNull(reference));
         [Pure]
         [DebuggerHidden]
-        public static BorrowedReference Borrow(this in NewReference reference)
+        public static BorrowedReference Borrow(this scoped in NewReference reference)
             => reference.IsNull() ? throw new NullReferenceException() : reference.BorrowNullable();
         [Pure]
         [DebuggerHidden]
-        public static BorrowedReference BorrowOrThrow(this in NewReference reference)
+        public static BorrowedReference BorrowOrThrow(this scoped in NewReference reference)
             => reference.IsNull() ? throw PythonException.ThrowLastAsClrException() : reference.BorrowNullable();
     }
 }

src/runtime/Native/StolenReference.cs

@@ -28,7 +28,7 @@ public static StolenReference Take(ref IntPtr ptr)
         }
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         [DebuggerHidden]
-        public static StolenReference TakeNullable(ref IntPtr ptr)
+        public static StolenReference TakeNullable(scoped ref IntPtr ptr)
         {
             var stolenAddr = ptr;
             ptr = IntPtr.Zero;

src/runtime/Runtime.cs

@@ -157,15 +157,8 @@ internal static void Initialize(bool initSigs = false)
             // Initialize modules that depend on the runtime class.
             AssemblyManager.Initialize();
             OperatorMethod.Initialize();
-            if (RuntimeData.HasStashData())
-            {
-                RuntimeData.RestoreRuntimeData();
-            }
-            else
-            {
-                PyCLRMetaType = MetaType.Initialize();
-                ImportHook.Initialize();
-            }
+            PyCLRMetaType = MetaType.Initialize();
+            ImportHook.Initialize();
             Exceptions.Initialize();
 
             // Need to add the runtime directory to sys.path so that we
@@ -269,8 +262,6 @@ internal static void Shutdown()
             {
                 // avoid saving dead objects
                 TryCollectingGarbage(runs: 3);
-
-                RuntimeData.Stash();
             }
 
             AssemblyManager.Shutdown();
@@ -832,7 +823,7 @@ public static int Py_Main(int argc, string[] argv)
 
         internal static IntPtr Py_GetBuildInfo() => Delegates.Py_GetBuildInfo();
 
-        const PyCompilerFlags Utf8String = PyCompilerFlags.IGNORE_COOKIE | PyCompilerFlags.SOURCE_IS_UTF8;
+        private static readonly PyCompilerFlags Utf8String = PyCompilerFlags.IGNORE_COOKIE | PyCompilerFlags.SOURCE_IS_UTF8;
 
         internal static int PyRun_SimpleString(string code)
         {
@@ -1715,7 +1706,7 @@ internal static bool PyType_IsSameAsOrSubtype(BorrowedReference type, BorrowedRe
         internal static NewReference PyType_GenericAlloc(BorrowedReference type, nint n) => Delegates.PyType_GenericAlloc(type, n);
 
         internal static IntPtr PyType_GetSlot(BorrowedReference type, TypeSlotID slot) => Delegates.PyType_GetSlot(type, slot);
-        internal static NewReference PyType_FromSpecWithBases(in NativeTypeSpec spec, BorrowedReference bases) => Delegates.PyType_FromSpecWithBases(in spec, bases);
+        internal static NewReference PyType_FromSpecWithBases(scoped in NativeTypeSpec spec, BorrowedReference bases) => Delegates.PyType_FromSpecWithBases(in spec, bases);
 
         /// <summary>
         /// Finalize a type object. This should be called on all type objects to finish their initialization. This function is responsible for adding inherited slots from a type�s base class. Return 0 on success, or return -1 and sets an exception on error.

src/runtime/StateSerialization/RuntimeData.cs

@@ -1,4 +1,4 @@
-using System;
+/*using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
@@ -210,3 +210,4 @@ internal static IFormatter CreateFormatter()
         }
     }
 }
+*/