Unfortunately this drops 2.7 binaries because there is no image that has both. However, from pypistats.org, it appears that our Python 2 user base is finally under 10%.

Also removes the Google groups embedding from the main web page because that no longer works.

Fixes #1822

Patch libev and c-ares configure scripts for M1

This updates the config.sub and config.guess files
for libev and c-ares to the versions that are packaged
with automake 1.16.5. This pulls in a version compatible
with Apples aarch64 chip.

Update the appveyor download url for pypi2.7-v7.3.1

M1 uses arm64 as a cpu identifier. This is not understood
by the two configure scripts, but appears to work when patched.

manylinux: disable -ffast-math

See failed builds at https://github.com/gevent/gevent/pull/1820/checks?check_run_id=3807405865

Support 3.10 now that the ABI is officially stable with 3.10rc1

It doesn't seem to crash locally. Not sure what's going on, but I doubt that's an important use-case (mixing gevent, threads and subinterpreters).

Change the way we detect compiled types to fix this.

Refs https://github.com/cython/cython/issues/4326

Link to, and quote from, https://www.reddit.com/r/RedditEng/comments/obqtfm/solving_the_three_stooges_problem/ on the success page.

Thanks to @denik for passing this on.

Get CI back in shape

Also try to opt-in to newer Python versions on AppVeyor, where possible.

Plus a PyPy fix, now that the tests are running again.

This is necessary on Ubuntu 20.04 (github actions) which has increased the minimum required key length. There are also changes in the test suite to account for this.

This is only a partial fix, more will be needed.