DRAFT: Enable different rust versions for host and guest

.github/workflows/cargo-publish.yml

@@ -49,7 +49,7 @@ jobs:
       - name: Hyperlight setup
         uses: hyperlight-dev/ci-setup-workflow@59673866360458f8dd035f4a9fa766aeebad2038 # v2.3.1
         with:
-          rust-toolchain: "1.90"
+          additional-toolchain-directory: src/hyperlight-js-runtime
           just-version: "1.51"
 
       - name: Install cargo-overlay-registry
@@ -101,7 +101,7 @@ jobs:
                     -p hyperlight-js-runtime
 
       - name: Authenticate with crates.io
-        uses: rust-lang/crates-io-auth-action@3268eb413133e2960fa4ae0e963ca76380c54cd9 # v1
+        uses: rust-lang/crates-io-auth-action@c6f97d42243bad5fab37ca0427f495c86d5b1a18 # v1
         id: crates-io-auth
 
       - name: Publish hyperlight-js-common

.github/workflows/dep_benchmarks.yml

@@ -56,7 +56,7 @@ jobs:
 
       - uses: hyperlight-dev/ci-setup-workflow@59673866360458f8dd035f4a9fa766aeebad2038 # v2.3.1
         with:
-          rust-toolchain: "1.90"
+          additional-toolchain-directory: src/hyperlight-js-runtime
           just-version: "1.51"
 
       - name: Install github-cli (Azure Linux)

.github/workflows/dep_build.yml

@@ -91,7 +91,7 @@ jobs:
 
     - uses: hyperlight-dev/ci-setup-workflow@59673866360458f8dd035f4a9fa766aeebad2038 # v2.3.1
       with:
-          rust-toolchain: "1.90"
+          additional-toolchain-directory: src/hyperlight-js-runtime
           just-version: "1.51"
 
     # Unlike upstream hyperlight, which builds its guests once per architecture
@@ -104,10 +104,11 @@ jobs:
     # to /usr/bin/ar when llvm-ar is missing from PATH, which yields a guest
     # link with every QuickJS and libc symbol undefined. Prefer a provisioned
     # llvm-ar when the runner image supplies one; otherwise use the active Rust
-    # toolchain's llvm-tools component, installing it if necessary.
+    # guest toolchain's llvm-tools component, installing it if necessary.
     - name: Set up LLVM guest toolchain (macOS)
       if: runner.os == 'macOS'
       shell: bash
+      working-directory: src/hyperlight-js-runtime
       run: |
         set -euo pipefail
         if command -v llvm-ar >/dev/null 2>&1; then

.github/workflows/npm-publish.yml

@@ -79,7 +79,7 @@ jobs:
       - name: Hyperlight setup
         uses: hyperlight-dev/ci-setup-workflow@59673866360458f8dd035f4a9fa766aeebad2038 # v2.3.1
         with:
-          rust-toolchain: "1.90"
+          additional-toolchain-directory: src/hyperlight-js-runtime
           just-version: "1.51"
 
       - name: Setup Node.js
@@ -94,10 +94,11 @@ jobs:
       # cannot produce ELF archives, and cargo-hyperlight silently falls back to
       # it when llvm-ar is absent from PATH, leaving every QuickJS and libc
       # symbol undefined at the guest link. Prefer a provisioned llvm-ar and
-      # fall back to the active Rust toolchain's llvm-tools component.
+      # fall back to the guest Rust toolchain's llvm-tools component.
       - name: Set up LLVM guest toolchain (macOS)
         if: runner.os == 'macOS'
         shell: bash
+        working-directory: src/hyperlight-js-runtime
         run: |
           set -euo pipefail
           if command -v llvm-ar >/dev/null 2>&1; then

CONTRIBUTING.md

@@ -118,3 +118,18 @@ For more detailed instructions on setting up GPG signing, see [GitHub's document
 ### Rust Analyzer
 
 If you are using the [Rust Analyzer](https://rust-analyzer.github.io/manual.html) then you may need to set the configuration option `rust-analyzer.rustfmt.extraArgs` to `["+nightly"]` to ensure that formatting works correctly as this project has a [`rustfmt.toml`](./rustfmt.toml) file that uses nightly features.
+
+### Rust Toolchains
+
+Host builds and tools use the root `rust-toolchain.toml`. The guest runtime
+uses a separate toolchain pinned in
+`src/hyperlight-js-runtime/rust-toolchain.toml`, allowing the host compiler to
+advance independently of guest target support.
+
+Build with:
+
+```sh
+just build
+```
+
+The build installs both toolchains and their required components automatically.

Justfile

@@ -24,8 +24,16 @@ export CMAKE_GENERATOR := if os() == "windows" { "Ninja" } else { "" }
 # host, so derive it rather than hardcoding x86_64.
 guest-target := arch() + "-hyperlight-none"
 
-ensure-tools:
-    cargo install cargo-hyperlight --locked
+# Temporary pin for guest toolchain selection: hyperlight-dev/cargo-hyperlight#83.
+cargo-hyperlight-rev := "5993b956fdcfd091a02ad3c3592baff67e0a2b9f"
+
+# Install the host and guest toolchains and components from their pin files.
+ensure-toolchains:
+    rustup toolchain install
+    cd src/hyperlight-js-runtime && rustup toolchain install
+
+ensure-tools: ensure-toolchains
+    cargo install cargo-hyperlight --git https://github.com/hyperlight-dev/cargo-hyperlight --rev {{ cargo-hyperlight-rev }} --locked
 
 # Check if npm is installed, install automatically if missing (Linux)
 [private]
@@ -46,7 +54,7 @@ check-license-headers:
     ./dev/check-license-headers.sh
 
 clippy target=default-target features="": (ensure-tools)
-    cargo hyperlight clippy -p hyperlight-js-runtime \
+    cd src/hyperlight-js-runtime && cargo hyperlight clippy -p hyperlight-js-runtime \
             --target={{ guest-target }} \
             --profile={{ if target == "debug" {"dev"} else { target } }} \
             -- -D warnings
@@ -113,11 +121,11 @@ build-trace target=default-target features="": (build-rust-trace target features
 build-native-runtime target=default-target:
     cargo build --manifest-path=./src/hyperlight-js-runtime/Cargo.toml --profile={{ if target == "debug" {"dev"} else { target } }}
 
-build-rust target=default-target features="":
+build-rust target=default-target features="": ensure-toolchains
     cd src/hyperlight-js && \
       cargo build {{ if features =="" {''} else if features=="no-default-features" {"--no-default-features" } else {"--no-default-features -F " + features } }} --profile={{ if target == "debug" {"dev"} else { target } }}
 
-build-rust-trace target=default-target features="":
+build-rust-trace target=default-target features="": ensure-toolchains
     cd src/hyperlight-js && \
       cargo build {{ if features =="" {'-F trace_guest'} else if features=="no-default-features" {"--no-default-features -F trace_guest" } else {"--no-default-features -F trace_guest," + features } }} --profile={{ if target == "debug" {"dev"} else { target } }}
 

rust-toolchain.toml

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "1.90"
-components = ["clippy", "llvm-tools", "rustfmt"]
+channel = "1.99.1"
+components = ["clippy", "rustfmt"]

src/hyperlight-js-runtime/rust-toolchain.toml

@@ -0,0 +1,3 @@
+[toolchain]
+channel = "1.90"
+components = ["clippy", "llvm-tools", "rust-src"]

src/hyperlight-js/Cargo.toml

@@ -37,7 +37,8 @@ libc = { version = "0.2", optional = true }
 windows-sys = { version = "0.61", features = ["Win32_Foundation", "Win32_System_Threading", "Win32_System_Registry", "Win32_System_WindowsProgramming"], optional = true }
 
 [build-dependencies]
-cargo-hyperlight = "0.1.14"
+# Temporary pin for guest toolchain selection: hyperlight-dev/cargo-hyperlight#83.
+cargo-hyperlight = { git = "https://github.com/hyperlight-dev/cargo-hyperlight", rev = "5993b956fdcfd091a02ad3c3592baff67e0a2b9f" }
 cfg_aliases = "0.2.1"
 serde_json = { version = "1.0" }
 

src/hyperlight-js/build.rs

@@ -230,9 +230,14 @@ fn build_js_runtime(custom: Option<PathBuf>) -> PathBuf {
         .canonicalize()
         .expect("hyperlight-js-runtime include directory not found");
     println!("cargo:rerun-if-changed={}", include_dir.display());
+    let toolchain_file = include_dir.with_file_name("rust-toolchain.toml");
+    println!("cargo:rerun-if-changed={}", toolchain_file.display());
     let cflags = format!("-I{} {QUICKJS_CFLAGS}", include_dir.display()).replace("\\", "\\\\");
 
     let mut cargo_cmd = cargo_hyperlight::cargo().unwrap();
+    cargo_cmd
+        .toolchain_file(&toolchain_file)
+        .unwrap_or_else(|error| panic!("Could not select JS guest toolchain: {error:#}"));
     let cmd = cargo_cmd
         .arg(if is_custom { "rustc" } else { "build" })
         .arg("--profile")
@@ -249,6 +254,8 @@ fn build_js_runtime(custom: Option<PathBuf>) -> PathBuf {
         .arg(&manifest_path)
         .arg("--locked")
         .env_clear_cargo()
+        // Host Clippy must not wrap the separately pinned guest compiler.
+        .env_remove("RUSTC_WORKSPACE_WRAPPER")
         .current_dir(runtime_dir)
         .env("HYPERLIGHT_CFLAGS", cflags);