[Bug sanitizer/68260] false positive with tsan

[dvyukov at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68260

--- Comment #4 from Dmitry Vyukov <dvyukov at google dot com> ---
Good point. I wonder if using -O2 fixes this.
We tend to always use tsan with -O2 for performance reasons. Tsan already
considerably slows down execution, and additional unnecessary memory accesses
and non-inlined trivial function calls (which there can be zillions in "modern
C++") with -O0 slow down execution even more.