typically changing the submodule paths wrecks repositories. you can try to repair it by deleting the directories and doing "git submodule update --init --recursive" from the bizhawk root. In my experience, git GUIs may mess something up here
Waterbox supports threads now, but they're not real threads on the host side because that's complicated and can be nondeterministic. Instead, everything is scheduled to share one host thread. This means that scheduling is actually cooperative and certain patterns of spinlocks and other nonsense can fail to work at all, but "regular" code probably will.
With this, add DobieStation PS2 core. This core was selected because it has threads and is otherwise simple to port; easy to build and a good core/frontend separation. It's not a wonderful core however, with low speed (made abysmally lower by our lack of real threads) and low compatibility, so it remains a curiosity for now.
Create an all new waterbox build environment:
WSL2 + Ubuntu 20.04 LTS (Other linuxes may work)
Musl libc with waterbox customizations
LLVM's libclang-rt, libunwind, libcxxabi, libcxx
Static linking to elf files
Compared with the old system, this is easier to set up a dev env for and easier to update in the future. The executables are larger but produce smaller savestates due to static linking. The modern toolchain means advanced library features and language features that sometimes appear in some upstream cores will be reusable.
YoshiRulz