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>
This "fixes" errors like these:
```
FAILED: obj/third_party/angle/angle_gpu_info_util/SystemInfo_vulkan.o
[...]
In file included from ../../third_party/wayland/src/src/wayland-client.h:40:
/nix/store/an42rhwn6ck2nix6caikrr4rvizknjhh-wayland-1.21.0-dev/include/wayland-client-protocol.h:1040:13: error: use of undeclared identifier 'wl_proxy_marshal_flags'
callback = wl_proxy_marshal_flags((struct wl_proxy *) wl_display,
^
[...]
/nix/store/an42rhwn6ck2nix6caikrr4rvizknjhh-wayland-1.21.0-dev/include/wayland-client-protocol.h:1392:87: error: use of undeclared identifier 'WL_MARSHAL_FLAG_DESTROY'
WL_SHM_POOL_DESTROY, NULL, wl_proxy_get_version((struct wl_proxy *) wl_shm_pool), WL_MARSHAL_FLAG_DESTROY);
^
[...]
fatal error: too many errors emitted, stopping now [-ferror-limit=]
```
At least for now (until Chromium updates their bundled Wayland version) it
seems best to use the bundled headers/versions to avoid version incompatibility
issues (we should hopefully be able to drop use_system_wayland_scanner though).
