diff --git a/.gitattributes b/.gitattributes
index 7e79b659e6..4521df9e43 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -8325,6 +8325,7 @@ tests/webtbs/tw9179.pp svneol=native#text/plain
 tests/webtbs/tw9187.pp svneol=native#text/plain
 tests/webtbs/tw9190.pp svneol=native#text/plain
 tests/webtbs/tw9209.pp svneol=native#text/plain
+tests/webtbs/tw9221.pp svneol=native#text/plain
 tests/webtbs/ub1873.pp svneol=native#text/plain
 tests/webtbs/ub1883.pp svneol=native#text/plain
 tests/webtbs/uw0555.pp svneol=native#text/plain
diff --git a/rtl/inc/wstrings.inc b/rtl/inc/wstrings.inc
index 0259b38069..e693fd9d0a 100644
--- a/rtl/inc/wstrings.inc
+++ b/rtl/inc/wstrings.inc
@@ -984,9 +984,10 @@ begin
         end;
       { Force nil termination in case it gets shorter }
       PWord(Pointer(S)+l*sizeof(WideChar))^:=0;
-{$ifndef FPC_WINLIKEWIDESTRING}
-      PWideRec(Pointer(S)-WideFirstOff)^.Len:=l*sizeof(WideChar);
-{$endif FPC_WINLIKEWIDESTRING}
+{$ifdef MSWINDOWS}
+      if not winwidestringalloc then
+{$endif MSWINDOWS}
+        PWideRec(Pointer(S)-WideFirstOff)^.Len:=l*sizeof(WideChar);
     end
   else
     begin
diff --git a/tests/webtbs/tw9221.pp b/tests/webtbs/tw9221.pp
new file mode 100644
index 0000000000..916c0b32e9
--- /dev/null
+++ b/tests/webtbs/tw9221.pp
@@ -0,0 +1,13 @@
+{%target=win32,win64}
+
+var
+  s: widestring;
+begin
+  winwidestringalloc:=false;
+  s:='1234';
+  SetLength(s, 10);
+  if Length(s) <> 10 then begin
+    writeln('Test failed!');
+    Halt(1);
+  end;
+end.