[Bug c++/68209] C++11 code compiled without -std=c++11 but doesn't work as expected

[mirzayanovmr at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68209

--- Comment #2 from MikeMirzayanov <mirzayanovmr at gmail dot com> ---
Right now code written as C++11 can be unintentionally compiled in C++98-mode
and it leads to incorrect behavior of the code.

What is the reason why it compiled on C++98? I expect that it is incorrect
syntax for C++98 and code doesn't match language grammatics. So expected
behavior is "compilation error".