--- a/src/testdir/test_vim9_class.vim
+++ b/src/testdir/test_vim9_class.vim
@@ -10502,6 +10502,20 @@ def Test_Object_Compare_With_Recursive_C
     assert_equal(true, result)
   END
   v9.CheckScriptSuccess(lines)
+
+  lines =<< trim END
+    vim9script
+
+    class C
+        public var nest: C
+    endclass
+    var o1 = C.new()
+    var o2 = C.new(C.new())
+
+    var result = o1 == o2
+    assert_equal(false, result)
+  END
+  v9.CheckScriptSuccess(lines)
 enddef
 
 " Test for using a compound operator from a lambda function in an object method

--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    515,
+/**/
     514,
 /**/
     513,

--- a/src/vim9class.c
+++ b/src/vim9class.c
@@ -3855,6 +3855,8 @@ object_equal(
 
     if (o1 == o2)
 	return TRUE;
+    if (o1 == NULL || o2 == NULL)
+	return FALSE;
 
     cl1 = o1->obj_class;
     cl2 = o2->obj_class;