[Bug c++/91215] Compiled program loops endlessly because of -O2 with g++ 8.3.0

[sboisvert at gydle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91215

--- Comment #1 from Sebastien Boisvert <sboisvert at gydle dot com> ---
As indicated in the minimum reproducer, returning 0 fixed this bug.

g++ reports this warning:

g++-8.3.0-infinite-loop-bug.cpp: In function 'int doY()':
g++-8.3.0-infinite-loop-bug.cpp:20:1: warning: no return statement in function
returning non-void [-Wreturn-type]
 }
 ^

Thanks