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Re: [msysGit] Re: [PATCH 01/14] Fix non-constant array creation

From
Marius Storm-Olsen <marius@storm-olsen.com>
Date
Aug 21, 2009, 19:49 UTC
Message-ID
<4A8EFA56.6050001@gmail.com>
In-Reply-To
<9d6091530908210926p61aa5ea6ya6a7b71f940fdf5a@mail.gmail.com>
Janos Laube said the following on 21.08.2009 18:26:
Show 9 quoted lines
>> MSVC compiles regex.c, so it must handle it. I'm fine with that.
> 
> msvc supports alloca, but regex.c doesn't make use of it per default 
> (you must define HAVE_ALLOCA_H in order to use it). basically _alloca
>  is fine for that task, but be aware that error handling on windows
> is a bit compilicated. when _alloca fails it throws a structured 
> exception, you must reset the stack and use traditional memory 
> allocation as fallback. see 
> http://msdn.microsoft.com/en-us/library/wb1s57t5.aspx. :-)

I must admit that I didn't look much at the surrounding code to know how large preimage->nr can get. But assuming variable-length array is handled the same way by the compiler as alloca(), and this code seems to be performing fine, I guess it's safe to say that this code won't be triggering any SEH, and thus we won't need to handle it?

So, given my assumptions I think we can just replace that one line with alloca(), nuke the free(), and everything is ok.

-- .marius

Previous: Janos LaubeNext: Johan 't Hart
Message 45 of 49 in “Build git with MSVC”
  1. 00/14 Build git with MSVCMarius Storm-Olsen, Aug 21, 2009
  2. 01/14 Fix non-constant array creationMarius Storm-Olsen, Aug 21, 2009
  3. 02/14 Avoid declaration after statementMarius Storm-Olsen, Aug 21, 2009
  4. 03/14 Define SNPRINTF_SIZE_CORR=1 for Microsoft Visual C++Marius Storm-Olsen, Aug 21, 2009
  5. 04/14 Add define guards to compat/win32.hMarius Storm-Olsen, Aug 21, 2009
  6. 05/14 Change regerror() declaration from K&R style to ANSI C (C89)Marius Storm-Olsen, Aug 21, 2009
  7. 06/14 mingw.c: Use the O_BINARY flag to open filesMarius Storm-Olsen, Aug 21, 2009
  8. 07/14 Fix __stdcall/WINAPI placement and function prototypeMarius Storm-Olsen, Aug 21, 2009
  9. 08/14 Test for WIN32 instead of __MINGW32_Marius Storm-Olsen, Aug 21, 2009
  10. 09/14 Avoid including windows.h in winansi.c for MSVC buildMarius Storm-Olsen, Aug 21, 2009
  11. 10/14 Add empty header files for MSVC portMarius Storm-Olsen, Aug 21, 2009
  12. 11/14 Add MinGW header files to build git with MSVCMarius Storm-Olsen, Aug 21, 2009
  13. 12/14 Add platform files for MSVC portingMarius Storm-Olsen, Aug 21, 2009
  14. 13/14 Add MSVC project filesMarius Storm-Olsen, Aug 21, 2009
  15. 14/14 Add README and gitignore file for MSVC buildMarius Storm-Olsen, Aug 21, 2009
  16. Thiago FarinaAug 23, 2009
  17. Reece DunnAug 23, 2009
  18. Marius Storm-OlsenAug 23, 2009
  19. Thiago FarinaAug 23, 2009
  20. Marius Storm-OlsenAug 24, 2009
  21. Frank LiAug 25, 2009
  22. Thiago FarinaAug 25, 2009
  23. Frank LiAug 27, 2009
  24. Thiago FarinaAug 27, 2009
  25. Erik Faye-LundSep 7, 2009
  26. Junio C HamanoAug 21, 2009
  27. Reece DunnAug 21, 2009
  28. Marius Storm-OlsenAug 22, 2009
  29. Paolo BonziniAug 28, 2009
  30. Johannes SixtAug 21, 2009
  31. Marius Storm-OlsenAug 21, 2009
  32. Frank LiAug 21, 2009
  33. 05/14 Change regerror() definition from K&R style to ANSI C (C89)Marius Storm-Olsen, Aug 21, 2009
  34. Frank LiAug 22, 2009
  35. Erik Faye-LundAug 24, 2009
  36. Junio C HamanoAug 21, 2009
  37. Johan 't HartAug 21, 2009
  38. Johannes SixtAug 21, 2009
  39. Junio C HamanoAug 21, 2009
  40. Marius Storm-OlsenAug 22, 2009
  41. Marius Storm-OlsenAug 22, 2009
  42. Erik Faye-LundAug 21, 2009
  43. Marius Storm-OlsenAug 21, 2009
  44. Janos LaubeAug 21, 2009
  45. Marius Storm-OlsenAug 21, 2009
  46. Johan 't HartAug 21, 2009
  47. Erik Faye-LundAug 22, 2009
  48. Junio C HamanoAug 21, 2009
  49. Junio C HamanoAug 21, 2009

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