cppcms-users

[Cppcms-users] Failing assertion in asynchronous application

[Julian P. <ju...@wh...>]

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Hallo,

today I discovered an assertion in booster::shared_ptr that fails under
specific circumstances in asynchronous applications.
If a client (browser) closes the current connection while its request is
still served and release_context() is called after the connection had
been closed already, the server exits with the following error message:

iweb2.fcgi: booster/booster/shared_ptr.h:305: T*
booster::shared_ptr<T>::operator->() const [with T =
cppcms::impl::cgi::connection]: Assertion `px != 0' failed.

Do I have to perform any check before I call release_context() or is
this considered to be a bug?

Thanks,
Julian
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Re: [Cppcms-users] Failing assertion in asynchronous application

[Artyom <art...@ya...>]

> 
> today I  discovered an assertion in booster::shared_ptr that fails under
> specific  circumstances in asynchronous applications.
> If a client (browser) closes the  current connection while its request is
> still served and release_context() is  called after the connection had
> been closed already, the server exits with  the following error message:


Can you give me the backtrace?

> 
> iweb2.fcgi:  booster/booster/shared_ptr.h:305:  T*
> booster::shared_ptr<T>::operator->() const [with T  =
> cppcms::impl::cgi::connection]: Assertion `px != 0' failed.
> 
> Do I  have to perform any check before I call release_context() or is
> this  considered to be a bug?

It may be the bug that was fixed in trunk, however trunk not really stable
at this point, so backtrace will help me to understand if this is it.

Artyom



      

Re: [Cppcms-users] Failing assertion in asynchronous application

[Julian P. <ju...@wh...>]

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> 
> Can you give me the backtrace?
> 
> It may be the bug that was fixed in trunk, however trunk not really stable
> at this point, so backtrace will help me to understand if this is it.
> 

The problem is: There is no backtrace. I ran the server with valgrind,
and after the assertion failure, the server exits without a backtrace.
Should I perhaps try with gdb instead of valgrind?
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Re: [Cppcms-users] Failing assertion in asynchronous application

[Artyom <art...@ya...>]

> 
> The problem is: There is no  backtrace. I ran the server with valgrind,
> and after the assertion failure,  the server exits without a backtrace.
> Should I perhaps try with gdb instead  of valgrind?

Yes, run program in gdb, and when assert happens just print

> bt

And see the trace.

Arryom


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