fanquake

Pushed for builds now that the mirrors are back up.

> FWIW, I found another Windows-specific bug in the upstream: https://github.com/miniupnp/miniupnp/pull/727. Rebased again, but can pull in this change + fixups on next push

> However, the changes in MSVC generated assembly code look quite significant. > Before stacking another performance deterioration change on top of the pile Isn't that because optimisations haven't been...

> Want to upstream the crc32 patch to match the others we have sitting there? Sure. Opened a PR in our crc32c subtree fork: https://github.com/bitcoin-core/crc32c-subtree/pull/7, and one in Google upstream:...

I don't think that's better. We have to keep all the redundant code, and now we are diverging from upstream for no reason.

Also, you're just moving the endianess testing into the code. The point is to drop all of this, and use generic code that doesn't require any tests at all. The...

Rebased, and switched the changes to CMake.

Seems like there's at least something which could/should be backported here? Maybe only the other change, given the newly broken code has only existed in master?

I've pulled #29776 in for 27.x. It could go into 26.x as well cc @glozow.

Concept ACK