Do not crash

src/Avalonia.Base/Utilities/KeywordParser.cs

@@ -17,6 +17,8 @@ namespace Avalonia.Utilities
             var ws = r.PeekWhitespace();
 
             var chars = r.TryPeek(ws.Length + keyword.Length);
+            if (chars.IsEmpty)
+                return -1;
             if (SpanEquals(chars.Slice(ws.Length), keyword.AsSpan()))
                 return chars.Length;
             return -1;

src/Markup/Avalonia.Markup.Xaml/XamlIl/CompilerExtensions/Transformers/AvaloniaXamlIlPropertyPathTransformer.cs

@@ -17,7 +17,8 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions.Transformers
             if (node is XamlIlAstXamlPropertyValueNode pv
                 && pv.Values.Count == 1
                 && pv.Values[0] is XamlIlAstTextNode text
-                && pv.Property.GetClrProperty().Getter.ReturnType.Equals(context.GetAvaloniaTypes().PropertyPath)
+                && pv.Property.GetClrProperty().Getter?.ReturnType
+                    .Equals(context.GetAvaloniaTypes().PropertyPath) == true
             )
             {
                 var parentScope = context.ParentNodes().OfType<AvaloniaXamlIlTargetTypeMetadataNode>()