Re: Re: [PATCH] git-compat-util.h: reduce optimization level to 1 on MinGW env.
Hi,
I'm sorry resend email many times... My GMail setting default to HTML format. So mail sent to Git ML is rejected...
---------------------------- Thanks for your reply.
> If changing the optimization level turns out to be the right fix, I
> would prefer to see this change made in the Makefile instead of
> git-compat-util.h.
Yes, I see. I think so. I shuld write optimization level change code to Makefile instead of git-compat-util.h.
2013/9/26 Jonathan Nieder <jrnieder@gmail.com>:
Show 56 quoted lines
> (cc-ing the Git for Windows maintainers)
> Hi,
>
> Wataru Noguchi wrote:
>
>> Git for Windows crashes when clone Japanese multibyte repository.
>> - Japanese Base Encoding is Shift-JIS.
>> - It happens Japanese multibyte directory name and too-long directory path
>> - Linux(ex. Ubuntu 13.04 amd64) can clone normally.
>> - example repository is here:
>>
>> git clone https://github.com/wnoguchi/mingw-checkout-crash.git
>>
>> - The reproduce crash repository contains following file only.
>> - following directory and file name is encoded for this commit log.
>> - actually file name is decoded.]
>> %E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%201-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%202-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%203-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%204-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%205-long-long-long-dirname/%E3%81%AF%E3%81%98%E3%82%81%E3%81%AB%E3%81%8A%E8%AA%AD%E3%81%BF%E3%81%8F%E3%81%A0%E3%81%95%E3%81%84.txt
>> - only one commit.
>>
>> This commit reduce gcc optimization level from O2 to O1 when MinGW Windows environment.
>>
>> Signed-off-by: Wataru Noguchi <wnoguchi.0727@gmail.com>
>
> Thanks.
>
>> ---
>> git-compat-util.h | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/git-compat-util.h b/git-compat-util.h
>> index a31127f..394c23b 100644
>> --- a/git-compat-util.h
>> +++ b/git-compat-util.h
>> @@ -90,6 +90,8 @@
>> #define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
>> #include <winsock2.h>
>> #include <windows.h>
>> +/* reduce gcc optimization level to 1 */
>> +#pragma GCC optimize ("O1")
>> #define GIT_WINDOWS_NATIVE
>> #endif
>
> Do you know why reducing the optimization level avoids a crash?
> Perhaps this is just masking the symptoms and the problem is still
> lurking.
>
> If changing the optimization level turns out to be the right fix, I
> would prefer to see this change made in the Makefile instead of
> git-compat-util.h. That way, the user building can still easily
> override the optimization settings to -O0 if they want to during a
> debugging session.
>
> What do you think?
>
> Hope that helps,
> JonathanHi,
Thanks for your advise.
> To find out what the real cause is, I suggest using a tool similar to
> valgrind. Valgrind does not run on Windows, but I DuckDuckWent e.g.
> http://code.google.com/p/drmemory/ as an alternative that could be tried
> to identify the problem.
I will try debugging by using any tools more real cause.
* Valgrind and drmemory, etc.
2013/9/26 Johannes Schindelin <Johannes.Schindelin@gmx.de>:
Show 30 quoted lines
> Hi,
>
> On Wed, 25 Sep 2013, Jonathan Nieder wrote:
>
>> Wataru Noguchi wrote:
>>
>> > - actually file name is decoded.]
>> > %E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%201-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%202-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%203-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%204-long-long-long-dirname/%E6%97%A5%E6%9C%AC%E8%AA%9E%E3%83%87%E3%82%A3%E3%83%AC%E3%82%AF%E3%83%88%E3%83%AA%205-long-long-long-dirname/%E3%81%AF%E3%81%98%E3%82%81%E3%81%AB%E3%81%8A%E8%AA%AD%E3%81%BF%E3%81%8F%E3%81%A0%E3%81%95%E3%81%84.txt
>> >
>> > This commit reduce gcc optimization level from O2 to O1 when MinGW
>> > Windows environment.
>>
>> Do you know why reducing the optimization level avoids a crash?
>
> I suspect that the optimization level causes smaller (or no) buffer bytes
> between data structures and the crash is the symptom of a buffer overflow.
> In that light, I think that reducing the optimization level is most likely
> just working around this particular issue, and other scenarios might still
> crash until we fix the underlying bug.
>
> Most likely the problem is with our Windows-specific UTF-8 handling, I
> would not be surprised if it is my "favorite" bug: an off-by-one.
>
> To find out what the real cause is, I suggest using a tool similar to
> valgrind. Valgrind does not run on Windows, but I DuckDuckWent e.g.
> http://code.google.com/p/drmemory/ as an alternative that could be tried
> to identify the problem.
>
> Ciao,
> Johannes
--
===========================
Wataru Noguchi
wnoguchi.0727@gmail.com
http://wnoguchi.github.io/
===========================
--
--
*** Please reply-to-all at all times ***
*** (do not pretend to know who is subscribed and who is not) ***
*** Please avoid top-posting. ***
The msysGit Wiki is here: https://github.com/msysgit/msysgit/wiki - Github accounts are free.
You received this message because you are subscribed to the Google
Groups "msysGit" group.
To post to this group, send email to msysgit@googlegroups.com
To unsubscribe from this group, send email to
msysgit+unsubscribe@googlegroups.com
For more options, and view previous threads, visit this group at
http://groups.google.com/group/msysgit?hl=en_US?hl=en
---
You received this message because you are subscribed to the Google Groups "msysGit" group.
To unsubscribe from this group and stop receiving emails from it, send an email to msysgit+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.
Wataru Noguchi
