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From: Jonathan Wakely <jwakely.gcc@gmail.com>
Date: Wed, 27 Mar 2019 00:29:00 -0000
Message-ID: <CAH6eHdS8quNZOnV_KoxRFj_t9VueKmJUFpTmUSN9GBh0AwkZXg@mail.gmail.com>
Subject: Re: Recursive SIGSEGV question
To: gcc-help <gcc-help@gcc.gnu.org>
Cc: Jonny Grant <jg@jguk.org>, Florian Weimer <fw@deneb.enyo.de>, Andrew Haley <aph@redhat.com>
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On Tue, 26 Mar 2019 at 06:13, Xi Ruoyao wrote:
> > C++ exceptions show a few clues when there is a crash, which is helpful, eg:
> >
> > // g++-8 -Wall -o cpp cpp.cpp
> > #include <vector>
> > int main()
> > {
> >      std::vector<int> v;
> >      return v.at(0);
> > }
> >
> >
> > $ ./cpp
> > terminate called after throwing an instance of 'std::out_of_range'
> >    what():  vector::_M_range_check: __n (which is 0) >= this->size()
> > (which is 0)
> > Aborted
>
> I'm not familiar with C++ exception.  Maybe we can convert some instances of
> unhandled signals to something like __gnu_cxx::unhandled_signal_exception, but I
> believe that would require ABI changes.

I don't think that's a good idea. Signals are not exceptions, and vice versa.