feat: build the backend on stable Rust

Author: mkroening

.github/workflows/ci.yml

@@ -12,8 +12,7 @@ jobs:
       RUSTFLAGS: -Dwarnings
     steps:
       - uses: actions/checkout@v4
-      # FIXME: use stable once rftrace supports stable
-      - uses: dtolnay/rust-toolchain@nightly
+      - uses: dtolnay/rust-toolchain@stable
         with:
           targets: x86_64-unknown-none
       - run: cargo clippy --all-features
@@ -45,9 +44,6 @@ jobs:
           sudo apt-get update
           sudo apt-get install uftrace
       - uses: mkroening/rust-toolchain-toml@main
-      - uses: dtolnay/rust-toolchain@nightly
-        with:
-          components: llvm-tools
       - name: Build
         run: make
       - name: Run
@@ -71,7 +67,6 @@ jobs:
         run: |
           sudo apt-get update
           sudo apt-get install uftrace
-      - uses: mkroening/rust-toolchain-toml@main
       - uses: dtolnay/rust-toolchain@nightly
         with:
           components: llvm-tools

rftrace/build.rs

@@ -30,7 +30,6 @@ fn build_backend() {
     let target = "x86_64-unknown-none";
 
     let mut cmd = cargo();
-    cmd.arg("+nightly");
     cmd.arg("rustc");
 
     cmd.args(["--target", target]);

rust-toolchain.toml

@@ -1,5 +1,4 @@
 [toolchain]
-channel = "nightly"
 components = [
     "llvm-tools-preview",
     "rustfmt",