Borland Delphi 5/7异常处理失效问题求助及底层实现咨询

执行TRow.CreateForIxf构造函数后，Delphi的try...except异常处理功能完全失效，程序直接崩溃。

测试函数及调用代码 #

异常处理测试函数 #

procedure vmDbg_TestExceptionsHandling(AMarker: string);
var
  i: integer;
begin
  i := UVmDll.DebugPoint(9002, PChar(AMarker)); // #define dbgpnt_HeapCheck  9002
  if i <> 1 then
    ToAppLogger(ll_ERROR, format('  %s->UVmDll.DebugPoint(9002)->heap integrity failure!', [AMarker]));

  //DBG:
  try
    // when Borland RTL space is somehow broken, it will crash here!
    raise Exception.Create('test exceptions#1 /' + AMarker);
  except
    on e: Exception do begin
      ToAppLogger(ll_ERROR, format('  %s->UVmDll.DebugPoint(99)->%s', [AMarker, ExcErrMsg(e)]));
    end;
  end;

  //DBG:
  try
    // inside ScriptVN.dll there is a special handling for point# 99 - it will throw a C++ exception
    UVmDll.DebugPoint(99, PChar(AMarker));
  except
    on e: Exception do begin
      ToAppLogger(ll_ERROR, format('  %s->UVmDll.DebugPoint(99)->%s', [AMarker, ExcErrMsg(e)]));
    end;
  end;

  //DBG:
  try
    // sometimes it may crash here...
    raise Exception.Create('test exceptions#2 /' + AMarker);
  except
    on e: Exception do begin
      ToAppLogger(ll_ERROR, format('  %s->UVmDll.DebugPoint(99)->%s', [AMarker, ExcErrMsg(e)]));
    end;
  end;
end;

测试调用代码 #

procedure vmDll_Jira790TestCase;
var
  n: integer;
  ixf: cpp_IInterface;
  rw, rwx, rwd: TRow;
begin
  isJira790Catch := true; 
  vmDbg_TestExceptionsHandling('Jira790TestCase.0'); //<-- here it works fine

  rwd := TRow.CreateDummy;
  vmDbg_TestExceptionsHandling('Jira790TestCase.1'); //<-- here it works fine

  rw := TRow.Create(true);
  vmDbg_TestExceptionsHandling('Jira790TestCase.2'); //<-- here it works fine

  ixf := UVmDll.DataTree__GetContainerInterface(rw.Engine);
  rwx := TRow.CreateForIxf(ixf); // <-- it crashes on leaving this constructor     
  vmDbg_TestExceptionsHandling('Jira790TestCase.3'); // <-- sometimes it crashes here
end;

问题表现与已做验证 #

• 测试函数核心目的是验证try...except是否能正常捕获异常，执行TRow.CreateForIxf前的三次调用均正常，之后调用时异常处理完全失效，程序直接崩溃
• 崩溃时调试器提示错误码0x0eedfade，无调试状态下Windows事件日志仅记录KERNELBASE.dll相关崩溃信息
• 已验证对象VMT有效、堆内存完整，但因不了解Borland Delphi 5/7异常处理底层实现，无法进一步定位问题

环境补充 #

• 单线程UI应用
• 仅在Windows Server 2012/2016/2019上出现崩溃，Windows 7/部分Win10版本运行正常
• 尝试兼容性模式无效

求助需求 #

• Borland Delphi 5/7异常处理底层实现的相关文档资料
• 手动排查异常处理结构正确性的方法，包括异常处理结构的类型、存储位置等细节

内容的提问来源于stack exchange，提问作者dmitry_bond