From 60606e61ef1082703219c0c119e21b9fd455af2e Mon Sep 17 00:00:00 2001
From: michael <michael@freepascal.org>
Date: Mon, 1 Apr 2019 17:25:29 +0000
Subject: [PATCH] * Patch from Ondrej Pokorny to make RegisterClassAlias
 thread-safe

git-svn-id: trunk@41818 -
---
 rtl/objpas/classes/cregist.inc | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/rtl/objpas/classes/cregist.inc b/rtl/objpas/classes/cregist.inc
index a40e4fc6d2..011776c56c 100644
--- a/rtl/objpas/classes/cregist.inc
+++ b/rtl/objpas/classes/cregist.inc
@@ -44,9 +44,14 @@ procedure RegisterClassAlias(AClass: TPersistentClass; const Alias: string);
   var
     I : integer;
   begin
-    i := ClassAliasList.IndexOf(Alias);
-    if I = -1 then
-      ClassAliasList.AddObject( Alias, TObject(AClass) );
+    ClassList.LockList;
+    try
+      i := ClassAliasList.IndexOf(Alias);
+      if I = -1 then
+        ClassAliasList.AddObject( Alias, TObject(AClass) );
+    finally
+      ClassList.UnlockList;
+    end;
   end;