[Bug c++/68383] Demangler stack overflow

[fiesh at zefix dot tv]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68383

--- Comment #3 from fiesh at zefix dot tv ---
Created attachment 36739
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36739&action=edit
Preprocessed c++ file