From: Dmitry D. Chernov <blackdoomer@yandex.ru>
Date: Tue, 19 Sep 2023 16:45:12 +0000 (+1000)
Subject: Fix LCLRefCount warning and possible use-after-free
X-Git-Url: https://deadsoftware.ru/gitweb?p=d2df-editor.git;a=commitdiff_plain;h=09c7e2fe60e25c431d1cea07282f471b8309d2c9

Fix LCLRefCount warning and possible use-after-free
Verbatim warning text: "WARNING: TMenuItem.Destroy with LCLRefCount>0. Hint: Maybe the component is processing an event?".
This was caused by a complex call chain of miRecentFileExecute() -> OpenMap() -> RefreshRecentMenu() -> RefillRecentMenu(), which result in the sender menu item being removed.
In such cases, Application.ReleaseComponent() should be used.
https://forum.lazarus.freepascal.org/index.php?topic=33591.0 - Topic: [SOLVED] How to delete a button on an OnClick event
https://www.lazarusforum.de/viewtopic.php?p=118333 - [gelöst]Was tun bei: Maybe the component is processing an event?
---

diff --git a/src/editor/f_main.pas b/src/editor/f_main.pas
index e4e0643..e2fdc20 100644
--- a/src/editor/f_main.pas
+++ b/src/editor/f_main.pas
@@ -2554,8 +2554,10 @@ end;
 procedure TMainForm.miRecentFileExecute (Sender: TObject);
 var
   s, fn: AnsiString;
+  n: LongInt;
 begin
-  s := RecentFiles[(Sender as TMenuItem).Tag];
+  n := (Sender as TMenuItem).Tag;
+  s := RecentFiles[n];
   fn := g_ExtractWadName(s);
   if FileExists(fn) then
     OpenMap(fn, g_ExtractFilePathName(s))
@@ -2585,7 +2587,7 @@ begin
     else
     begin
       menu.Delete(i);
-      MI.Destroy();
+      Application.ReleaseComponent(MI);
     end;
   end;