The build was failing with the following error:
```
[18950/51180] SOLINK ./libvk_swiftshader.sotls_transport_interface/dtls_transport_interface.omputils.o[K.otch.oos.oKx/unbundle:default)fault)ault)
FAILED: libvk_swiftshader.so libvk_swiftshader.so.TOC
python3 "../../build/toolchain/gcc_solink_wrapper.py" --readelf="readelf" --nm="nm" --sofile="./libvk_swiftshader.so" --tocfile="./libvk_swiftshader.so.TOC" --output="./libvk_swiftshader.so" -- clang++ -shared -Wl,-soname="libvk_swiftshader.so" -Wl,-Bsymbolic -Wl,--version-script=../../third_party/swiftshader/src/Vulkan/vk_swiftshader.lds -fuse-ld=lld -Wl,--fatal-warnings -Wl,--build-id=sha1 -fPIC -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now -Wl,--icf=all -Wl,--color-diagnostics -Wl,-mllvm,-instcombine-lower-dbg-declare=0 -flto=thin -Wl,--thinlto-jobs=all -Wl,--thinlto-cache-dir=thinlto-cache -Wl,--thinlto-cache-policy=cache_size=10\%:cache_size_bytes=40g:cache_size_files=100000 -Wl,-mllvm,-import-instr-limit=30 -fwhole-program-vtables -Wl,--no-call-graph-profile-sort -m64 -no-canonical-prefixes -Wl,-O2 -Wl,--gc-sections -rdynamic -Wl,-z,defs -Wl,--as-needed -nostdlib++ -Wl,--lto-O0 -fsanitize=cfi-vcall -fsanitize=cfi-icall -o "./libvk_swiftshader.so" @"./libvk_swiftshader.so.rsp"
ld.lld: error: unable to find library -l:libffi_pic.a
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
```
This turned out to be a regression from b6b51374fc. That change was
bad/undesirable in the first place and I only applied it to quickly fix
another build error caused by incompatible wayland-protocols header
files from a newer system version (Chromium bundles version 1.21 while
we already package 1.26).
The better fix for that wayland-protocols build issue is to pull in a
patch that is already used/tested by the Arch package [0] and seems to
originate from [1] (not sure if that patch was formally submitted yet).
Alternatives to that patch would be to (we should probably first try the
first approach if need be):
1) Build with wayland-protocols 1.21 from the system (by overriding the
Nixpkgs package).
2) Dynamically link against libffi by patching [2] to use the other
branch (`default_toolchain == "//build/toolchain/cros:target"`).
Some additional details can be found in the GitHub PR [3].
Huge thanks to Lorenz Brun for his great analysis that enabled me to fix
the build so that we can finally merge the update to Chromium M105
(which contains many important security fixes!).
[0]: a353833a5a
[1]: https://bugs.chromium.org/p/angleproject/issues/detail?id=7582#c1
[2]: https://source.chromium.org/chromium/chromium/src/+/refs/tags/105.0.5195.52:build/config/linux/libffi/BUILD.gn
[3]: https://github.com/NixOS/nixpkgs/pull/189033
Co-Authored-By: Lorenz Brun <lorenz@brun.one>
Its now running unit tests, and the headless frontend is packaged as
well. The latter is a bit inconsistent, on the OpenGL backend it will
always fail to create an SDL+OpenGL instance, causing a crash.
The Vulkan backend mostly works fine, although it might need a few
restarts before it decides to show graphics. Better than nothing though.
