[Bug demangler/79406] Demangler crash

[jeanmichael.celerier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79406

--- Comment #1 from Jean-Michaël Celerier <jeanmichael.celerier at gmail dot com> ---
This stems from the usage of the following lambda expression : 

    [&] (auto&&... args) { return
this->fun(std::forward<decltype(args)>(args)...); }

Unlike bug 77950 the enclosing function is not a template but a simple class
constructor that takes two int16_t.

The arguments passed to the lambda are either : 

* (std::weak_ptr<void>)
* (std::weak_ptr<void>, const std::string&)