How to select cmake binary based on host platform instead of target platform?

[Lev1ty]

I'm trying to cross-compile some static cxx libs using cmake within a genrule. The target platform is linux x86_64 and the my laptop (host) is macos arm64. The error message is buck-out/v2/gen/root/fa160be2e4e88f1c/third-party/__abseil-cpp-build__/sh/genrule.sh: line 5: ../../../tools/__cmake-linux-x86_64-archive__/cmake-linux-x86_64-archive/bin/cmake: cannot execute binary file. So suspecting that the cmake that is being selected to run is linux instead of the intended macos.

Is there some way to select cmake based on host instead of target platform?

# third-party/BUCK

genrule(
    name = "protobuf-build",
    cmd = "$(location //tools:cmake-archive)/`cat $(location //tools:cmake-path)` -S$(location :protobuf-src) -B. -DCMAKE_INSTALL_PREFIX=$OUT -DCMAKE_CXX_STANDARD=20 -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_PREFIX_PATH=$(location :abseil-cpp-build) -Dprotobuf_ABSL_PROVIDER=package && make -j8 && make install",
    out = "protobuf-build",
)

# tools/BUCK

alias(
    name = "cmake-archive",
    actual = select({
        "@root//platforms/config:linux-x86_64": ":cmake-linux-x86_64-archive",
        "@root//platforms/config:macos-arm64": ":cmake-macos-arm64-archive",
    }),
    visibility = [
        "//third-party:abseil-cpp-build",
        "//third-party:protobuf-build",
    ],
)

alias(
    name = "cmake-path",
    actual = select({
        "@prelude//os:linux": ":cmake-linux-path",
        "@prelude//os:macos": ":cmake-macos-path",
    }),
    visibility = [
        "//third-party:abseil-cpp-build",
        "//third-party:protobuf-build",
    ],
)

http_archive(
    name = "cmake-linux-x86_64-archive",
    sha256 = "ac31f077ef3378641fa25a3cb980d21b2f083982d3149a8f2eb9154f2b53696b",
    strip_prefix = "cmake-3.30.1-linux-x86_64",
    urls = ["https://github.com/Kitware/CMake/releases/download/v3.30.1/cmake-3.30.1-linux-x86_64.tar.gz"],
)

genrule(name = "cmake-linux-path", cmd = "echo bin/cmake> $OUT", out = "cmake-linux-path")

http_archive(
    name = "cmake-macos-arm64-archive",
    sha256 = "51e12618829b811bba6f033ee8f39f6192da1b6abb20d82a7899d5134e879a4c",
    strip_prefix = "cmake-3.30.1-macos-universal",
    urls = ["https://github.com/Kitware/CMake/releases/download/v3.30.1/cmake-3.30.1-macos-universal.tar.gz"],
)

genrule(name = "cmake-macos-path", cmd = "echo CMake.app/Contents/bin/cmake> $OUT", out = "cmake-macos-path")

# platforms/config/BUCK

config_setting(
    name = "linux-x86_64",
    constraint_values = [
        "@prelude//cpu/constraints:x86_64",
        "@prelude//os/constraints:linux",
    ],
)

config_setting(
    name = "macos-arm64",
    constraint_values = [
        "@prelude//cpu/constraints:arm64",
        "@prelude//os/constraints:macos",
    ],
)