Error when compiling Rust on Aarch64 MacOS

[tyb0807]

Hi,

I'm very new to the field, so please let me know if the information I communicate here is useful enough for debugging.

I have the following dependency in MODULE.bazel

bazel_dep(name = "rules_rust", version = "0.41.1")
rust = use_extension("@rules_rust//rust:extensions.bzl", "rust")
rust.toolchain(
    edition = "2024",
    versions = ["1.77.2"],
)
use_repo(rust, "rust_toolchains")
register_toolchains("@rust_toolchains//:all")

When running a simple blaze test command, I get the following error (I've omitted the more verbose parts):

ERROR: .../external/rules_rust~/util/process_wrapper/BUILD.bazel:31:36: Compiling Rust (without process_wrapper) bin process_wrapper (6 files) [for tool] failed: (Exit 1): sandbox-exec failed: error executing Rustc command 
  ...
error: linking with `external/zig_sdk/tools/aarch64-macos-none/c++` failed: exit status: 1
  |
  = note: env -u ...
  = note: error: unable to find dynamic system library 'resolv' using strategy 'paths_first'. searched paths: ...

Does anybody know what's happening here, and how to fix this please?

[illicitonion]

Welcome, and thanks for the issue! If you can post a full git repo we can clone and run, that'd help to be able to debug. It looks like you're wiring up a zig C++ toolchain?

[DhashS]

I'm also seeing this (albeit with a WORKSPACE based config) when trying to use zig to make a hermetic cc toolchain work. The core of the issue seems to be the fact that a hermetic cc_toolchain kinda by definition needs to not depend on the host -- generally where one receives the host SDK from.

The relevant issue are these ones:

• Support local OSX SDK uber/hermetic_cc_toolchain#10
  • this shows that the OSX SDK isn't being picked up, and that the team isn't willing to pull from the host
• [darwin aarch64 cgo] regression in 0.8.0-1366-gfc302f00a ziglang/zig#10299 (comment)
  • this shows that the SDK's are available from apple, so theoretically this could be integrated into the hermetic cc project if the macos toolchain is enabled ... or something

This really only crops up if you try and go full hermetic with BAZEL_DO_NOT_DETECT_CPP_TOOLCHAIN=1 since otherwise the host sysroot is picked up via probably some xcrun shenanigans.

Until then (or until the rules_rust team drops

rules_rust/rust/platform/triple_mappings.bzl

Line 180 in 67b3571

"darwin": ["-lSystem", "-lresolv"],

this line) it'll be impossible to compile with a no-host hermetic CC toolchain since the don't detect host toolchain thing is an --action_env thing, which makes it global in a way that i'm unable to see how to specifically exclude rules_rust from.

[marvin-hansen]

@DhashS consider trying a LLVM toolchain setup with sysroot as it usually creates less fuzz.

See this example: https://github.com/marvin-hansen/examples/tree/main/rust-tutorial/01-hello-clang

For a LLVM with sysroot, see the cross compile example:
https://github.com/marvin-hansen/examples/tree/main/rust-tutorial/02-hello-cross