https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68159
--- Comment #4 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
(In reply to fiesh from comment #3)
> I ran into a problem that is possibly the same issue.
>
> echo 'void
> _ZSt7forwardIRKZN5Write14DataMapGrammarISt20back_insert_iteratorISsEEC4EvEUlR
> T_E_EOS5_RNSt16remove_referenceIS5_E4typeE() {} int main() {}' | gcc -xc -
> -o /tmp/a.out && gdb /tmp/a.out
>
> On gdb 7.9.1, 7.10, and 7.10.50.20151117-cvs, this results in
>
> Reading symbols from /tmp/a.out...cp-support.c:1595: demangler-warning:
> unable to demangle
> '_ZSt7forwardIRKZN5Write14DataMapGrammarISt20back_insert_iteratorISsEEC4EvEUl
> RT_E_EOS5_RNSt16remove_referenceIS5_E4typeE' (demangler failed with signal
> 11)
> Unable to dump core, use `ulimit -c unlimited' before executing GDB next
> time.
> cp-support.c:1608: demangler-warning: unable to demangle
> '_ZSt7forwardIRKZN5Write14DataMapGrammarISt20back_insert_iteratorISsEEC4EvEUl
> RT_E_EOS5_RNSt16remove_referenceIS5_E4typeE' (demangler failed with signal
> 11)
>
> The binary was compiled with gcc 4.9.3. If it's a different problem, I'll
> open up a separate ticket.
Your issue is a dup of PR61321, which is different.
