[Bug target/67478] gcc-5.1.0/gcc-5.2.0 undefined symbol std::__once_callable in AIX 6.1

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67478

--- Comment #10 from David Edelsohn <dje at gcc dot gnu.org> ---
The libstdc++ build process was updated to recognize LTS symbols.  Please use
GCC 5.3 or later.