fix #2280

Configuration/GlobalAssemblyInfo.cs

@@ -15,7 +15,7 @@ internal static class RevisionClass
 	public const string Major = "3";
 	public const string Minor = "6";
 	public const string Build = "3";
-	public const string Revision = "2568";
+	public const string Revision = "2569";
 
         public const string MainVersion = Major + "." + Minor;
 	public const string FullVersion = Major + "." + Minor + "." + Build + "." + Revision;

Configuration/Version.defs

@@ -1,4 +1,4 @@
-%COREVERSION%=3
-%REVISION%=2568
 %MINOR%=6
+%REVISION%=2569
+%COREVERSION%=3
 %MAJOR%=3

Release/pabcversion.txt

@@ -1 +1 @@
-3.6.3.2568
+3.6.3.2569

ReleaseGenerators/PascalABCNET_version.nsh

@@ -1 +1 @@
-!define VERSION '3.6.3.2568'
+!define VERSION '3.6.3.2569'

TestSuite/Qpoint1.pas

@@ -0,0 +1,7 @@
+// #2280
+begin
+  var a: sequence of object := Seq(object(1));
+  //Ошибка: Левый операнд операции ?. должен иметь ссылочный тип
+  var o := a?.First;
+  Assert(o.Equals(1));
+end.

TreeConverter/TreeConversion/semantic_checks_for_sugar.cs

@@ -123,7 +123,7 @@ namespace PascalABCCompiler.TreeConverter
             else if (av.type is compiled_type_node ctn1)
                 t = ctn1.compiled_type;
 
-            if (!av.type.is_class && !(t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable<>)))
+            if (!av.type.is_class && !av.type.IsInterface && !(t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable<>)))
                 AddError(av.location, "OPERATOR_DQ_MUST_BE_USED_WITH_A_REFERENCE_TYPE_VALUETYPE");
         }