std::system_error on calc example about cpp-peglib HOT 7 CLOSED

g++ -I .. -std=c++11 calc.cc -pthread

$ ./a.out 2+3*4
terminate called after throwing an instance of 'std::system_error'
  what():  Unknown error -1
Aborted (core dumped)
$ g++ --version
g++ (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

(gdb) bt
#0  0x00007ffff72400a7 in raise () from /lib64/libc.so.6
#1  0x00007ffff7241458 in abort () from /lib64/libc.so.6
#2  0x00007ffff7b32975 in __gnu_cxx::__verbose_terminate_handler() () from /usr/lib64/libstdc++.so.6
#3  0x00007ffff7b309f6 in ?? () from /usr/lib64/libstdc++.so.6
#4  0x00007ffff7b30a41 in std::terminate() () from /usr/lib64/libstdc++.so.6
#5  0x00007ffff7b30c58 in __cxa_throw () from /usr/lib64/libstdc++.so.6
#6  0x00007ffff7b86dbf in std::__throw_system_error(int) () from /usr/lib64/libstdc++.so.6
#7  0x000000000041590a in std::call_once<peg::DefinitionReference::get_rule() const::{lambda()#1}>(std::once_flag&, peg::DefinitionReference::get_rule() const::{lambda()#1}&&) (__once=..., __f=<unknown type in /amd.home/home/i57/mulbrich/tmp/cpp-peglib-master/example/a.out, CU 0x15b, DIE 0x5f779>)
    at /usr/include/c++/4.8/mutex:794
#8  0x0000000000408684 in peg::DefinitionReference::get_rule (this=0x66fba8) at ../peglib.h:1485
#9  0x0000000000409df0 in peg::ParserGenerator::DetectLeftRecursion::visit (this=0x7fffffffd8d0, ope=...) at ../peglib.h:1744
#10 0x0000000000408a00 in peg::DefinitionReference::accept (this=0x66fba8, v=...) at ../peglib.h:1507