Hi Greg, I tried v9-0001 on macOS arm64 on current master. I think everything looks good.
One new thing. It looks like part of 0003 moved into 0001 in this rebase. In v9-0001, the autoconf and meson builds no longer read the stdatomic option and always define USE_STDATOMIC_H. So 0001 is not opt-in anymore, and a target without lock-free 64-bit atomics now fails at configure. The commit message still says the default is "no". Thanks, Shihao
