From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: Jonny Grant <jg@jguk.org>
Cc: libstdc++@gcc.gnu.org
Subject: Re: libstdc++ Chapter 28. Demangling example
Date: Fri, 31 Mar 2023 17:18:15 +0100 [thread overview]
Message-ID: <CAH6eHdQ3yUo4ZE351zvEM3rqtvBoAGRumwU4w0tDaxshG+ua6Q@mail.gmail.com> (raw)
In-Reply-To: <03e9c7d6-95a0-bd2e-fa31-91919ad76f3f@jguk.org>
On Fri, 31 Mar 2023 at 16:24, Jonny Grant <jg@jguk.org> wrote:
>
> Hello
>
> I tried out this code. Maybe I'm doing something wrong?
>
> https://godbolt.org/z/Y78h4f1W6
>
> https://gcc.gnu.org/onlinedocs/gcc-12.2.0/libstdc++/manual/manual/ext_demangling.html
>
> However only get reduced output after status -2 is returned:
>
> std::bad_exception =>
>
> Looks like std::cout gets broken by the nullptr realname (that's a frustration). So I put an if(realname) in the godbolt link above.
N.B. passing a null pointer to printf("%s", ptr) is undefined.
Printing "(null)" is not required by the standards.
Anyway, the exception classes haven't printed their mangled name for
many many years, if they ever did. Only the second part of the
example, using typeid, is valid.
> Maybe it's also a good time to update the example abi::__cxa_demangle call from those 0 parameters to be NULL?
Maybe nullptr.
next prev parent reply other threads:[~2023-03-31 16:18 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-31 15:24 Jonny Grant
2023-03-31 16:18 ` Jonathan Wakely [this message]
2023-03-31 20:38 ` Jonny Grant
2023-04-04 11:26 ` Jonathan Wakely
2023-04-12 15:09 ` Jonny Grant
2023-04-12 15:36 ` Jonathan Wakely
2023-04-12 16:07 ` Jonny Grant
2023-04-18 13:00 ` Jonny Grant
2023-04-18 14:49 ` Jonathan Wakely
2023-04-18 22:50 ` Jonny Grant
2023-04-18 23:12 ` Jonathan Wakely
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