[Bug c++/84707] [8 Regression] internal compiler error: Segmentation fault (tree_check()/duplicate_decls())

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84707

--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Started with r253489.  Before that:
error: ‘namespace _GLOBAL__N_1 { }’ conflicts with a previous declaration
 namespace {}