diff --git a/.gitattributes b/.gitattributes
index c81eb35b43..3e4e711fc0 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -12777,6 +12777,7 @@ tests/webtbs/tw2250.pp svneol=native#text/plain
 tests/webtbs/tw22502.pp svneol=native#text/plain
 tests/webtbs/tw22561.pp svneol=native#text/plain
 tests/webtbs/tw2259.pp svneol=native#text/plain
+tests/webtbs/tw22593.pp svneol=native#text/plain
 tests/webtbs/tw2260.pp svneol=native#text/plain
 tests/webtbs/tw2266.pp svneol=native#text/plain
 tests/webtbs/tw2267.pp svneol=native#text/plain
diff --git a/compiler/defcmp.pas b/compiler/defcmp.pas
index b8267a01b5..fe49c84f43 100644
--- a/compiler/defcmp.pas
+++ b/compiler/defcmp.pas
@@ -1560,7 +1560,8 @@ implementation
                if assigned(def_to.typesym) and
                   (tclassrefdef(def_to).pointeddef.typ=forwarddef) then
                  begin
-                   if (def_from.typesym=def_to.typesym) then
+                   if (def_from.typesym=def_to.typesym) or
+                      (fromtreetype=niln) then
                     eq:=te_equal;
                  end
                else
diff --git a/tests/webtbs/tw22593.pp b/tests/webtbs/tw22593.pp
new file mode 100644
index 0000000000..bafe85ce76
--- /dev/null
+++ b/tests/webtbs/tw22593.pp
@@ -0,0 +1,25 @@
+{ %norun }
+
+{$ifdef fpc}
+{$mode objfpc}
+{$endif}
+
+type
+  tc = class
+  end;
+  tcc = class of tc;
+  tc3 = class;
+
+  tc2 = class
+    constructor create(c: tcc = nil; c3: tc3 = nil);
+  end;
+
+  tc3 = class
+  end;
+
+constructor tc2.create(c: tcc = nil; c3: tc3 = nil);
+begin
+end;
+
+begin
+end.