buck2: 'clang++' is not recognized as an internal or external command, operable program or batch file.

Hey there!

Trying to get a buck “hello world” building on Windows. I have this BUCK file:

rust_binary(
    name = "hello_world",
    srcs = ["hello.rs"],
    crate_root = "hello.rs",
)

and this toolchains\BUCK:

load("@prelude//toolchains:rust.bzl", "system_rust_toolchain")
load("@prelude//toolchains:genrule.bzl", "system_genrule_toolchain")
load("@prelude//toolchains:cxx.bzl", "system_cxx_toolchain")
load("@prelude//toolchains:python.bzl", "system_python_bootstrap_toolchain")

system_genrule_toolchain(
    name = "genrule",
    visibility = ["PUBLIC"],
)

system_rust_toolchain(
    name = "rust",
    default_edition = "2021",
    visibility = ["PUBLIC"],
)

system_cxx_toolchain(
    name = "cxx",
    visibility = ["PUBLIC"],
)

system_python_bootstrap_toolchain(
    name = "python_bootstrap",
    visibility = ["PUBLIC"],
)

When I try to buck2 build //:hello_world, I get this:

Local command returned non-zero exit code 1
Reproduce locally: `"buck-out\\v2\\gen\\prelude\\fb50fd37ce946800\\python_bootstrap\\tools\\__win_python_wrapper__\\win_ ...<omitted>... \\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\hello_world-link-diag.args" (run `buck2 log what-failed` to get the full command)`
stdout:
stderr:
error: linking with `buck-out\v2\gen\root\fb50fd37ce946800\__hello_world__\__linker_wrapper.bat` failed: exit code: 1
  |
  = note: "cmd" "/c" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\__linker_wrapper.bat" "-fno-use-linker-plugin" "-Wl,--dynamicbase" "-Wl,--disable-auto-image-base" "-m64" "-Wl,--high-entropy-va" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\self-contained\\crt2.o" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\rsbegin.o" "C:\\Users\\steve\\Documents\\GitHub\\buck-rust-hello\\buck-out\\v2\\tmp\\root\\fb50fd37ce946800\\__hello_world__\\rustc\\_buck_309d5f84a6053e4a\\rustcciRgVe\\symbols.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.hello_world.aeb6c6e0-cgu.0.rcgu.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.hello_world.aeb6c6e0-cgu.1.rcgu.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.hello_world.aeb6c6e0-cgu.2.rcgu.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.hello_world.aeb6c6e0-cgu.3.rcgu.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.hello_world.aeb6c6e0-cgu.4.rcgu.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.hello_world.aeb6c6e0-cgu.5.rcgu.o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\extras\\hello_world\\hello_world.1l3753u24tlzpzc9.rcgu.o" "-L" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link-deps-0" "-L" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-Wl,-Bstatic" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libstd-e363be82127e72d4.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libpanic_unwind-271c0a4c2400bd0e.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libobject-3b3a88ddf57ad9b8.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libmemchr-c38acbaaa0512e61.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libaddr2line-a777dde688506f47.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libgimli-00e812c5215e2bb4.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\librustc_demangle-9824443ffde90bb7.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libstd_detect-c9cae9f57d72c5d8.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libhashbrown-80b5e088fad27661.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libminiz_oxide-25b744457ec6a6b9.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libadler-b662208514509737.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\librustc_std_workspace_alloc-70e1db2cbff7c5e3.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libunwind-bc622eac43f92150.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libcfg_if-da38528f9991ea5d.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\liblibc-0217604e5fc185ea.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\liballoc-094368c19a10127d.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\librustc_std_workspace_core-9310325d5d5607bd.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libcore-5c3fe6fc6388f93c.rlib" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libcompiler_builtins-d765c9bc514400ee.rlib" "-Wl,-Bdynamic" "-lkernel32" "-ladvapi32" "-luserenv" "-lkernel32" "-lws2_32" "-lbcrypt" "-lgcc_eh" "-l:libpthread.a" "-lmsvcrt" "-lmingwex" "-lmingw32" "-lgcc" "-lmsvcrt" "-luser32" "-lkernel32" "-Wl,--nxcompat" "-nostartfiles" "-L" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-L" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\self-contained" "-o" "buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\static_pic\\hello_world.exe" "-Wl,--gc-sections" "-no-pie" "-nodefaultlibs" "@buck-out\\v2\\gen\\root\\fb50fd37ce946800\\__hello_world__\\bin-pic-static_pic-link\\__hello_world-link_linker_args.txt" "C:\\Users\\steve\\.rustup\\toolchains\\stable-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\rsend.o"
  = note: 'clang++' is not recognized as an internal or external command,
          operable program or batch file.



error: aborting due to previous error


Build ID: 767daac4-04b8-4412-8f4b-9953bafed010
Jobs completed: 3. Time elapsed: 0.5s. Cache hits: 0%. Commands: 1 (cached: 0, remote: 0, local: 1)
BUILD FAILED
Failed to build 'root//:hello_world (prelude//platforms:default#fb50fd37ce946800)'

Now, what’s weird about this is that clang++ is in my path:

$ clang++
clang++: error: no input files

I am not sure what I am doing wrong here, but any pointers would be greatly appreciated.