Windows support?

[Zeed-gn]

I'm using latest commit with git override:

bazel_dep(name = "toolchains_llvm", version = "1.1.2")
git_override(
  module_name = "toolchains_llvm",
  commit = "4ab573b1b87a57791ef2f9ccee71cbad80a2abb9",
  remote = "https://github.com/bazel-contrib/toolchains_llvm",
)

llvm = use_extension("@toolchains_llvm//toolchain/extensions:llvm.bzl", "llvm")
llvm.toolchain(
    name = "llvm_toolchain",
    llvm_version = "19.1.0",
)
use_repo(llvm, "llvm_toolchain")
register_toolchains("@llvm_toolchain//:all")

And for some reason:

ERROR: C:/users/user/_bazel_user/df37aufx/external/googletest~/BUILD.bazel:170:11: Compiling googlemock/src/gmock_main.cc failed: (Exit 2): cl.exe failed: error executing CppCompile command (from target @@googletest~//:gtest_main) C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.37.32822\bin\HostX64\x64\cl.exe @bazel-out/x64_windows-fastbuild/bin/external/googletest~/_objs/gtest_main/gmock_main.obj.params
cl : Command line error D8021 : invalid numeric argument '/Werror'

Works fine on linux though.

[philwo]

I just tried to use this on Windows, but ran into similar issues.

Looks like Windows is not supported (yet?), because both llvm_repo_impl as well as llvm_config_impl just silently produce empty repositories. As far as I understand the code, toolchains_llvm does nothing on Windows, thus llvm.toolchain(...) definitions in the main MODULE.bazel do not have any effect.

There are some Windows LLVM releases defined in the llvm_distributions.bzl, but I don't know how they could be used. Maybe only for cross-compiling from Linux?