ci: merge bitcoin#27314, #28954, introduce dependency options in GitHub Actions builds, fix multiprocess builds, bump to Clang 18

[kwvg]

Additional Information

• bitcoin#27314 has been backported in this PR as bitcoin#25838 (backported in dash#6384) broke Clang depends builds and this PR introduces Clang depends builds in CI.

• Support for multiprocess builds were enabled proper in dash#6143 but unfortunately, the configuration params for multiprocess builds were not processed by CI as the build variant was not added to matrix.sh (source). This is evident by comparing two variants with Boost::Process enablement (--with-boost-process), linux64_fuzz (source) and linux64_multiprocess (source).

  Looking at a develop (6a51ab2) build, the fuzz build has it enabled (source) while the multiprocess build doesn't (source) despite both scripts having the enablement argument.

• bitcoin#28954 has been backported to fix a problem associated with multiprocess runs (build)

• Unlike the GitLab build, the GitHub build more-or-less builds the same set of depends seven times (source) as neither the GitLab nor the GitHub build use ./ci/dash/build_depends.sh and therefore, BUILD_TARGET has no effect there (it directly starts building depends, defining only HOST, source).

  But GitLab CI defines DEP_OPTS (source) manually, uses it (source) and uses the same set of depends for multiple build variants (for example, x86_64-pc-linux-gnu-debug is used by linux64-build, linux64_cxx20-build, linux64_sqlite-build and more, source). GitHub does no such re-use and therefore each build variant corresponds to a depends variant.

  We have attempted to get the depends built in GitLab and GitHub Actions to be at par with each other, below should be a table to illustrate expected parameters.

  Target	DEP_OPTS	GitLab CI	GitHub Actions
  arm-linux-gnueabihf	None	arm-linux-gnueabihf	arm-linux
  x86_64-w64-mingw32	None	x86_64-w64-mingw32	None
  x86_64-apple-darwin	None	x86_64-apple-darwin	None
  x86_64-pc-linux-gnu	DEBUG=1	x86_64-pc-linux-gnu-debug	linux64_cxx20, linux64_fuzz, linux64_sqlite, linux64_ubsan
  x86_64-pc-linux-gnu	NO_WALLET=1	x86_64-pc-linux-gnu-nowallet	linux64_nowallet
  x86_64-pc-linux-gnu	DEBUG=1 MULTIPROCESS=1 CC=clang-18 CXX=clang++-18	x86_64-pc-linux-gnu-multiprocess	linux64_multiprocess, linux64_tsan

  x86_64-w64-mingw32 and x86_64-apple-darwin are currently unimplemented in GitHub Actions

  • The fuzz build will continue to use GCC-built depends instead of Clang-built depends as originally planned as Clang-built depends are multiprocess-enabled and currently multiprocess and fuzz don't play nice together (see upstream build failure for example, source, corresponding with local failure, source).

• Clang has been bumped to 18 in anticipation of bitcoin#30201, which will drop (native_llvm, formerly known as native_clang) and mandate the presence of Clang 18 or higher for cross-compilation.

• The version attribute in the develop container's docker-compose.yml has been dropped as the attribute has been deprecated in the compose spec (source).

• To avoid LLDB's "personality set failed: Operation not permitted" error caused by its attempt at disabling ASLR for debugging (source), the container will now operate under relaxed restrictions (seccomp=unconfined). As disabling ASLR is valuable when debugging and the container isn't used by CI but is meant for individual developers, we have opted to relax restrictions instead of skipping ASLR disablement.

  This does not affect CI as these relaxations are defined in the docker-compose.yml of the develop container, which inherits from the CI container but is a container of its own.

Breaking Changes

None expected

Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have made corresponding changes to the documentation
• I have assigned this pull request to a milestone (for repository code-owners and collaborators only)

[github-actions]

This pull request has conflicts, please rebase.