diff --git a/.gitattributes b/.gitattributes
index def95a29de..1c7e0777c3 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -14087,6 +14087,7 @@ tests/webtbs/tw2647.pp svneol=native#text/plain
 tests/webtbs/tw26482.pp svneol=native#text/pascal
 tests/webtbs/tw2649.pp svneol=native#text/plain
 tests/webtbs/tw2651.pp svneol=native#text/plain
+tests/webtbs/tw26536.pp svneol=native#text/plain
 tests/webtbs/tw2656.pp svneol=native#text/plain
 tests/webtbs/tw2659.pp svneol=native#text/plain
 tests/webtbs/tw26599.pp svneol=native#text/pascal
diff --git a/compiler/ncal.pas b/compiler/ncal.pas
index 90250933fc..1c1fa24943 100644
--- a/compiler/ncal.pas
+++ b/compiler/ncal.pas
@@ -3977,7 +3977,7 @@ implementation
                       (assigned(aktassignmentnode) and
                        (aktassignmentnode.right=self) and
                        (nf_assign_done_in_right in aktassignmentnode.flags) and
-                       aktassignmentnode.left.isequal(para.left)))) or
+                       actualtargetnode(@aktassignmentnode.left)^.isequal(actualtargetnode(@para.left)^)))) or
                     { the compiler expects that it can take the address of parameters passed by reference in
                       the case of const so we can't replace the node simply by a constant node
                       When playing with this code, ensure that
diff --git a/tests/webtbs/tw26536.pp b/tests/webtbs/tw26536.pp
new file mode 100644
index 0000000000..293cb6d6ef
--- /dev/null
+++ b/tests/webtbs/tw26536.pp
@@ -0,0 +1,40 @@
+{$MODE OBJFPC}
+program test;
+
+type
+   TBaseClass = class
+      function PrintSelf(): TBaseClass; inline; // has to be inline for the bug to manifest
+   end;
+   
+   TSubClass = class(TBaseClass)
+   end;
+
+function TBaseClass.PrintSelf(): TBaseClass; inline;
+begin
+   Writeln(PtrUInt(Self));
+   Result := nil;
+   Writeln(PtrUInt(Self)); // prints 0!
+   if not assigned(self) then
+     halt(1);
+end;
+
+procedure NoOp(var Dummy: TBaseClass);
+begin
+end;
+
+
+var
+   Instance, Variable: TBaseClass;
+   res: longint;
+begin
+   Instance := TSubClass.Create();
+   Variable := nil;
+
+   NoOp(Variable); // this call is important for the bug to manifest
+   Variable := Instance;
+   // object being invoked has to be cast to a different type for the bug to manifest
+   // return value has to be assigned to the variable being used as "self"
+   Variable := TSubClass(Variable).PrintSelf();
+
+   Instance.Free();
+end.