060a2a64d40d75fecb60b7d2b9946a67e46aa6fc ci: remove boost thread installation (fanquake)
06e1d7d81d5a56d136c6fc88f09a2b0654a164f9 build: don't build or use Boost Thread (fanquake)
7097add83c8596f81be9edd66971ffd2486357eb refactor: replace Boost shared_mutex with std shared_mutex in sigcache (fanquake)
8e55981ef834490c438436719f95cbaf888c4914 refactor: replace Boost shared_mutex with std shared_mutex in cuckoocache tests (fanquake)
Pull request description:
This replaces `boost::shared_mutex` and `boost::unique_lock` with [`std::shared_mutex`](https://en.cppreference.com/w/cpp/thread/shared_mutex) & [`std::unique_lock`](https://en.cppreference.com/w/cpp/thread/unique_lock).
Even though [some concerns were raised](https://github.com/bitcoin/bitcoin/issues/16684#issuecomment-726214696) in #16684 with regard to `std::shared_mutex` being unsafe to use across some glibc versions, I still think this change is an improvement. As I mentioned in #21022, I also think trying to restrict standard library feature usage based on bugs in glibc is not only hard to do, but it's not currently clear exactly how we do that in practice (does it also extend to patching out use in our dependencies, should we be implementing more runtime checks for features we are using, when do we consider an affected glibc "old enough" not to worry about? etc). If you take a look through the [glibc bug tracker](https://sourceware.org/bugzilla/describecomponents.cgi?product=glibc) you'll no doubt find plenty of (active) bug reports for standard library code we already using. Obviously not to say we shouldn't try and avoid buggy code where possible.
Two other points:
[Cory mentioned in #21022](https://github.com/bitcoin/bitcoin/pull/21022#issuecomment-769274179):
> It also seems reasonable to me to worry that boost hits the same underlying glibc bug, and we've just not happened to trigger the right conditions yet.
Moving away from Boost to the standard library also removes the potential for differences related to Boosts configuration. Boost has multiple versions of `shared_mutex`, and what you end up using, and what it's backed by depends on:
* The version of Boost.
* The platform you're building for.
* Which version of `BOOST_THREAD_VERSION` is defined: (2,3,4 or 5) default=2. (see [here](https://www.boost.org/doc/libs/1_70_0/doc/html/thread/build.html#thread.build.configuration) for some of the differences).
* Is `BOOST_THREAD_V2_SHARED_MUTEX` defined? (not by default). If so, you might get the ["less performant, but more robust"](https://github.com/boostorg/thread/issues/230#issuecomment-475937761) version of `shared_mutex`.
A lot of these factors are eliminated by our use of depends, but users will have varying configurations. It's also not inconceivable to think that a distro, or some package manager might start defining something like `BOOST_THREAD_VERSION=3`. Boost tried to change the default from 2 to 3 at one point.
With this change, we no longer use Boost Thread, so this PR also removes it from depends, the build system, CI etc.
Previous similar PRs were #19183 & #20922. The authors are included in the commits here.
Also related to #21022 - pthread sanity checking.
ACKs for top commit:
laanwj:
Code review ACK 060a2a64d40d75fecb60b7d2b9946a67e46aa6fc
vasild:
ACK 060a2a64d40d75fecb60b7d2b9946a67e46aa6fc
Tree-SHA512: 572d14d8c9de20bc434511f20d3f431836393ff915b2fe9de5a47a02dca76805ad5c3fc4cceecb4cd43f3ba939a0508178c4e60e62abdbaaa6b3e8db20b75b03
0dade9154d2e5d4b1725fbe27720d54396c4db1d fuzz: remove no-longer-necessary packages from fuzzbuzz config (fanquake)
Pull request description:
I take it this is actively being used, given [comments in #20560](https://github.com/bitcoin/bitcoin/pull/20560#issuecomment-743747317); so remove old dependencies from setup.
ACKs for top commit:
practicalswift:
ACK 0dade9154d2e5d4b1725fbe27720d54396c4db1d
Tree-SHA512: 781466776575e6051d0dddf4101bd057e484648f63e8e967240fefbf4b5832cacda6f6543708a0c368214a1efe0d60d371da78d7a920646cb93f1a4752aaf639
8d306862ef077f2a71931372dd6a2efa05188c84 ci: Add fuzzbuzz integration (practicalswift)
Pull request description:
Add fuzzbuzz integration.
Just like #15338 enabled optional FreeBSD building via Cirrus CI (`.cirrus.yml`) this PR adds optional fuzzing via fuzzbuzz (`.fuzzbuzz.yml`).
Having this merged makes is easier for people to fuzz Bitcoin Core (via their forked repos) using their fuzzbuzz account and then hopefully submit coverage increasing corpus additions upstreams to to https://github.com/bitcoin-core/qa-assets.
Historically it has been mostly been me and MarcoFalke who submit test cases to `qa-assets`, but with this change hopefully more people will join the hunt for coverage increasing fuzzing inputs :)
Top commit has no ACKs.
Tree-SHA512: c7d8e354996c673da36cc9add260383c82a5325bfaa7ce6141ad6cd6b7d6adf3a6c900ea2db17fb70147b3625fa7f6a1ff8ba813aeaa299f316d8f6cabb3a65c
