Hi Christian, We haven't found a good way either. Our idea is to put PJ_THROW() macro to replace throw(), which can somehow be used by SWIG to generate the exception specs. Regards, Ming On Tue, Sep 25, 2018 at 4:21 AM Christian Hoff <christian_hoff@xxxxxxx> wrote: > > Hello Ming and all, > > I have now done some research into SWIG and exceptions. After reading > the SWIG documentation, I found out that SWIG indeed parses the C++ > exception specification to figure out for what types of exceptions > "catch(..)" should be generated (see > http://www.swig.org/Doc3.0/SWIGDocumentation.html#SWIGPlus_exception_specifications > ). Exception types that are specified in the exception specification are > automatically propagated to the higher language (Java, C# etc.). Now > that we need to remove the exception specification, we lose that > capability. Thanks to Ming for the hint. However there is the > possibility to adapt the SWIG interface file > ("pjsip-apps/src/swig/pjsua2.i") and to add explicit "%catches" > statements for each method that describe which types of exceptions the > method could possibility throw. So I guess I need to rework my patch for > this. I just hope that I will find some way to avoid having to annotate > every method with "%catches".... I'll see. Or if someone knows how to do > it, then I would be very grateful for a reply. > > > Best regards, > > Christian > > > On 24/09/18 12:43, Christian Hoff wrote: > > Hello Ming, > > > > thanks for your reply! I will have a look into the SWIG topic this > > evening and will let you know my findings. > > > > > > Best regards, > > > > Christian > > > > > > On 24/09/18 09:03, Ming wrote: > >> Hi Christian, > >> > >> We apologize for the delay in response. We're currently reviewing it > >> and have also managed to do some testing. While for C/C++, this seems > >> to be okay, we're still considering how to best handle this for our > >> Android and Java (via SWIG binding), which may still need the "throw" > >> specifications in order for the developers to know that the functions > >> may throw some exceptions. > >> > >> If you have any feedback regarding this, please let us know. > >> > >> Best regards, > >> Ming > >> > >> On Mon, Sep 24, 2018 at 2:32 PM Christian Hoff > >> <christian_hoff@xxxxxxx> wrote: > >>> Hello all, > >>> > >>> some feedback for this patch is still appreciated. In general I am > >>> getting somewhat frustrated about the collaboration with people who > >>> want > >>> to contribute to the project. Already in the past other people have > >>> posted patches here to this list, but did not get any response - not > >>> even a response what needs to be changed for the patch to be > >>> accepted. I > >>> think this is not a good mode of collaboration. Everyone who posts a > >>> patch here to this mailing list has done this with the intention to > >>> help > >>> the project PJSIP to move along (and has spent much time developing the > >>> patch), so you should at least return the favour and review the patch. > >>> > >>> This particular issue that I am trying to address with my patch (that > >>> the PJSUA2 headers don't compile against C++17) is an issue that you > >>> will eventually need to fix anyhow, so why not fix it right now? As of > >>> now, modern versions of GCC use C++ 14 by default, it is only a matter > >>> of time until C++ 17 will become the default and people will start > >>> complaining that there are compile errors from the PJSUA2 headers. > >>> > >>> Besides this, my own app uses PJSUA2 with C++ 17 features, so I would > >>> have to revert back to C++14 if this patch is not accepted upstream. > >>> This would be really unnecessary. So I would really appreciate a patch > >>> review. > >>> > >>> Best regards, > >>> > >>> Christian > >>> > >>> > >>> On 18/09/18 20:57, Christian Hoff wrote: > >>>> Hello all, > >>>> Hello Ming & Riza, > >>>> > >>>> do you have any feedback regarding this patch for C++ 17 support? I am > >>>> also willing to rework it if required, but some feedback would be > >>>> nice. > >>>> > >>>> > >>>> Thanks in advance and kind regards, > >>>> > >>>> Christian > >>>> > >>>> > >>>> On 12/09/18 18:23, Christian Hoff wrote: > >>>>> Hello all, > >>>>> > >>>>> currently it is not possible to compile a pjsua2 application with > >>>>> C++17. The reason is that C++17 removes support for dynamic exception > >>>>> specifications (that is "throws ..." declarations at the end of a > >>>>> function). Unfortunately PJSUA2 makes heavy use of exception > >>>>> specifications and most PJSUA2 functions are declared as "throw > >>>>> (Error)" - meaning that they can throw an exception of type "Error" > >>>>> that the programmer is supposed to catch. > >>>>> > >>>>> The consequence is that a lot of compile errors can be observed when > >>>>> compiling a pjsua2 application with C++17. The compile errors look as > >>>>> follows: > >>>>> > >>>>> /usr/local/include/pjsua2/json.hpp:80:33: error: ISO C++17 does not > >>>>> allow dynamic exception specifications > >>>>> virtual string saveString() throw(Error); > >>>>> ^~~~~ > >>>>> > >>>>> The compile of the same application worked fine when using the C++14 > >>>>> standard, but it got broken when I switched from C++14 to the C++17 > >>>>> standard. > >>>>> > >>>>> See > >>>>> https://www.bfilipek.com/2017/05/cpp17-details-fixes-deprecation.html#removing-deprecated-exception-specifications-from-c17 > >>>>> > >>>>> and > >>>>> http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0003r0.html > >>>>> for more background about the removal of exception specifications. > >>>>> > >>>>> To make the application compile again, I had to remove "throw(Error)" > >>>>> in the whole PJSUA2 source code and include files. This seems to be > >>>>> the only viable and good fix for this issue. I wrote my own "sed" > >>>>> script to do that and made some cosmetic corrections afterwards. Then > >>>>> I generated the attached patch file. Could you please apply this > >>>>> patch to the code base or give me feedback what I still need to > >>>>> improve? I verified that pjsip compiles fine with the patch applied. > >>>>> > >>>>> Thank you very much! > >>>>> > >>>>> > >>>>> Best regards, > >>>>> > >>>>> Christian > >>> _______________________________________________ > >>> Visit our blog: http://blog.pjsip.org > >>> > >>> pjsip mailing list > >>> pjsip@xxxxxxxxxxxxxxx > >>> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > >> _______________________________________________ > >> Visit our blog: http://blog.pjsip.org > >> > >> pjsip mailing list > >> pjsip@xxxxxxxxxxxxxxx > >> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > > > > > > _______________________________________________ > > Visit our blog: http://blog.pjsip.org > > > > pjsip mailing list > > pjsip@xxxxxxxxxxxxxxx > > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > > > _______________________________________________ > Visit our blog: http://blog.pjsip.org > > pjsip mailing list > pjsip@xxxxxxxxxxxxxxx > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org _______________________________________________ Visit our blog: http://blog.pjsip.org pjsip mailing list pjsip@xxxxxxxxxxxxxxx http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org
