[Bug c++/125656] "warning: left shift count >= width of type [-Wshift-count-overflow]" inaccurate

[mattreecebentley at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125656

--- Comment #11 from Matt Bentley <mattreecebentley at gmail dot com> ---
ps. The constexpr check on set_overflow_to_zero's only to reduce codegen, that
shift can't become >= bitwidth.