[Bug c++/95559] GCC fails to compile "{{}}" in some versions

[haoxintu at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95559

--- Comment #3 from Haoxin Tu <haoxintu at gmail dot com> ---
(In reply to Haoxin Tu from comment #2)
> $g++-8 test.cc ; ./a.out
> 0

Here is 

> $g++-8 bug.cc ; ./a.out
> 0