On Thu, 2025-03-27 at 10:49 +0000, Jonathan Wakely via Gcc-help wrote:
> On Thu, 27 Mar 2025 at 10:48, Tom Kacvinsky via Gcc-help
> <gcc-help@xxxxxxxxxxx> wrote:
> >
> > On Thu, Mar 27, 2025 at 6:28 AM Tom Kacvinsky <tkacvins@xxxxxxxxx> wrote:
> >
> > > Hi,
> > >
> > > I have a shared library that was built without linking to libstd++.so.6.
> > > The mangled named
> > > is _Z3St3absl. But I can't it resolved in the libraries I link against.
> > > Where does this symbol originate?
> > >
> >
> > Answering my own question - it's defined as a builtin.
>
> I don't think so, it's define in <bits/std_abs.h> like so:
>
> #ifndef __CORRECT_ISO_CPP_STDLIB_H_PROTO
> inline long
> abs(long __i) { return __builtin_labs(__i); }
> #endif
>
> So it's either provided by your C library (which is the case for
> Solaris, IIRC) or it's an inline function which should be define in
> every object file that uses it.
On Linux computers with GCC you should use the --demangle option to GNU nm or
programmatically the <cxxabi.h> header with its abi::__cxa_demangle function
as documented on
https://gcc.gnu.org/onlinedocs/libstdc++/manual/ext_demangling.html
For a concrete example see the RefPerSys GPL project in my signature (it should
become an inference engine).
Regards
--
Basile STARYNKEVITCH <basile@xxxxxxxxxxxxxxxxx>
8 rue de la Faïencerie http://starynkevitch.net/Basile/
92340 Bourg-la-Reine https://github.com/bstarynk
France https://github.com/RefPerSys/RefPerSys
