diff --git a/NETGenerator/NETGenerator.cs b/NETGenerator/NETGenerator.cs
index d419091b2..4fd0ed606 100644
--- a/NETGenerator/NETGenerator.cs
+++ b/NETGenerator/NETGenerator.cs
@@ -5275,6 +5275,11 @@ namespace PascalABCCompiler.NETGenerator
                     if (!(value.type.is_generic_parameter && value.type.base_type != null && value.type.base_type.is_class && value.type.base_type.base_type != null))
                         must_push_addr = true;
                 }
+                else if (value.conversion_type != null && (value.conversion_type.is_generic_parameter))
+                {
+                    if (!(value.conversion_type.is_generic_parameter && value.conversion_type.base_type != null && value.conversion_type.base_type.is_class && value.conversion_type.base_type.base_type != null))
+                        must_push_addr = true;
+                }
             }
             ParamInfo pi = helper.GetParameter(value.parameter);
             if (pi.kind == ParamKind.pkNone)
@@ -7090,6 +7095,8 @@ namespace PascalABCCompiler.NETGenerator
             {
                 if (value.obj.type.is_generic_parameter)
                     il.Emit(OpCodes.Constrained, helper.GetTypeReference(value.obj.type).tp);
+                else if (value.obj.conversion_type != null && value.obj.conversion_type.is_generic_parameter)
+                    il.Emit(OpCodes.Constrained, helper.GetTypeReference(value.obj.conversion_type).tp);
                 il.EmitCall(OpCodes.Callvirt, mi, null);
             }
 
@@ -7219,6 +7226,8 @@ namespace PascalABCCompiler.NETGenerator
             {
                 if (value.obj.type.is_generic_parameter)
                     il.Emit(OpCodes.Constrained, helper.GetTypeReference(value.obj.type).tp);
+                else if (value.obj.conversion_type != null && value.obj.conversion_type.is_generic_parameter)
+                    il.Emit(OpCodes.Constrained, helper.GetTypeReference(value.obj.conversion_type).tp);
                 il.EmitCall(OpCodes.Callvirt, mi, null);
             }
             EmitFreePinnedVariables();
diff --git a/TestSuite/generics35.pas b/TestSuite/generics35.pas
new file mode 100644
index 000000000..a7b5ea5b4
--- /dev/null
+++ b/TestSuite/generics35.pas
@@ -0,0 +1,22 @@
+var i: integer;
+type
+  I1 = interface
+    procedure p1;
+  end;
+  
+  r1 = record(I1)
+    public procedure p1;
+    begin
+      i := 1;
+    end;
+  end;
+  
+procedure p1<T>(a: T); where T: I1;
+begin
+  I1(a).p1;
+end;
+
+begin
+  p1(new r1);
+  assert(i = 1);
+end.
\ No newline at end of file
diff --git a/TestSuite/generics36.pas b/TestSuite/generics36.pas
new file mode 100644
index 000000000..9cb262def
--- /dev/null
+++ b/TestSuite/generics36.pas
@@ -0,0 +1,18 @@
+var i: integer;
+type
+  r1 = record(System.ICloneable)
+    public function Clone: object;
+    begin
+      i := 1;
+    end;
+  end;
+  
+procedure p1<T>(a: T); where T: System.ICloneable;
+begin
+  System.ICloneable(a).Clone;
+end;
+
+begin
+  p1(new r1);
+  assert(i = 1);
+end.
\ No newline at end of file