添加语言时Delphi内存泄漏

Question

添加语言时Delphi内存泄漏

who*_*ddy 6 delphi memory-leaks delphi-xe

Delphi XE,Windows 7 64位

当您向空应用程序添加语言支持时,您将收到内存泄漏(FastMM4).

如何重现:

创建新的VCL表单应用程序
修改.dpr并添加 ReportMemoryLeaksOnShutdown := True;
构建/运行应用程序并关闭应用程序 - >未报告泄漏
现在添加一种语言(项目 - >语言 - >添加)
再次构建/运行并关闭应用程序 - >内存泄漏？

FastMM4完整调试模式报告:

--------------------------------2013/7/16 14:54:34--------------------------------
A memory block has been leaked. The size is: 12

This block was allocated by thread 0x17EC, and the stack trace (return addresses) at the time was:
40455E 
40952D 
4094C8 
409834 
409941 
450058 
74548D76 [Unknown function at FirstHookFunc]
7778FA1A [ZwOpenKey]
75924033 [OpenRegKey]
759240AE [OpenRegKey]
777FA71A [Unknown function at RtlUlonglongByteSwap]

The block is currently used for an object of class: Unknown

The allocation number is: 6

Current memory dump of 256 bytes starting at pointer address 7EF9A610:
6E 00 6C 00 2D 00 42 00 45 00 00 00 41 58 0D 7A 00 00 00 00 C1 A6 F9 7E 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 2E 00 00 00 5E 45 40 00 DD 99 40 00 6D 71 4B 00 98 65 40 00 04 66 40 00
77 A6 40 00 98 7C 4B 00 AA 33 8D 76 F2 9E 7A 77 C5 9E 7A 77 00 00 00 00 EC 17 00 00 EC 17 00 00
1F 9A 40 00 53 7F 42 00 2C 65 40 00 EA 68 40 00 E3 7C 4B 00 AA 33 8D 76 F2 9E 7A 77 C5 9E 7A 77
00 00 00 00 00 00 00 00 00 00 00 00 08 00 00 00 00 00 00 00 B6 5C 27 4D 5C 12 4C 00 80 80 80 80
49 A3 D8 B2 80 80 80 80 00 00 00 00 F9 B7 F9 7E 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
65 00 00 00 5E 45 40 00 A7 50 40 00 22 56 40 00 DC 50 40 00 5F 72 4B 00 78 96 44 00 8E 72 4B 00
98 65 40 00 04 66 40 00 77 A6 40 00 98 7C 4B 00 EC 17 00 00 EC 17 00 00 7A 45 40 00 C5 50 40 00
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--------------------------------2013/7/16 14:54:34--------------------------------
This application has leaked memory. The small block leaks are (excluding expected leaks registered by pointer):

5 - 12 bytes: Unknown x 1

Note: Memory leak detail is logged to a text file in the same folder as this application. To disable this memory leak check, undefine "EnableMemoryLeakReporting".

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现在到了有趣的部分:删除语言并再次运行 - >泄漏停留!

我可以通过删除除.dpr和.res文件之外的所有项目相关文件(.dproj,.dproj2007,.dsk等等)来删除泄漏.

有人可以解释一下发生了什么吗？

UPDATE

使用详细日志中的地址,似乎我在System.Pas中发现了泄漏:

var
  PreferredLanguagesOverride: PChar = nil;

...    
procedure SetLocaleOverride(const NewPreferredLanguages: string);
var
  L: Integer;
begin
  if PreferredLanguagesOverride <> nil then
    FreeMem(PreferredLanguagesOverride);
  L := Length(NewPreferredLanguages);
  if L > 0 then
  begin
    Inc(L);
    GetMem(PreferredLanguagesOverride, L * SizeOf(Char));
    MoveChars(NewPreferredLanguages[1], PreferredLanguagesOverride^, L);
  end;
end;

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调用SetLocaleOverride并为其保留内存PreferredLanguagesOverride PChar.我扫描了System.Pas,FreeMem(PreferredLanguagesOverride)但这是唯一的情况!

UPDATE2

我找到了delphi调用SetLocaleOverride例程的原因:

添加语言支持时,将创建一个注册表项,其名称为可执行完整路径,当前系统区域设置为值:HKEY_CURRENT_USER\Software\Embarcadero\Locales

删除此键可防止delphi调用SetLocaleOverride例程.

题: