ci: Build statically linked bpf-linker in CI

- Download LLVM builds from Rust CI.
- Always link libLLVM statically.
- For now, do it only for x86_64.

Author: vadorovsky

.github/workflows/ci.yml

@@ -14,11 +14,11 @@ on:
 
 env:
   CARGO_TERM_COLOR: always
+  LLVM_SHA: 0b5eb7ba7bd796fb39c8bb6acd9ef6c140f28b65
+  LLVM_SYS_191_PREFIX: /opt/rust-dev
+  LLVM_TARGET: x86_64-unknown-linux-musl
 
 jobs:
-  llvm:
-    uses: ./.github/workflows/llvm.yml
-
   lint-stable:
     runs-on: ubuntu-22.04
 
@@ -55,18 +55,12 @@ jobs:
         rust:
           - stable
           - beta
-          # TODO: unpin nightly. There was a regression in
-          # https://github.com/rust-lang/rust/compare/1cec373f6...becebb315 that causes
-          # tests/btf/assembly/anon_struct_c.rs to fail to link.
-          - nightly-2024-04-16
-        llvm:
-          - 18
-          - source
+          - nightly
     name: rustc=${{ matrix.rust }} llvm=${{ matrix.llvm }}
-    needs: llvm
 
     env:
       RUST_BACKTRACE: full
+      RUSTFLAGS: -L /opt/rust-dev/lib
 
     steps:
       - uses: actions/checkout@v4
@@ -114,15 +108,11 @@ jobs:
           sudo apt -y install clang gcc-multilib
 
       - name: Install LLVM
-        if: matrix.llvm != 'source'
         run: |
           set -euxo pipefail
-          wget -qO- https://apt.llvm.org/llvm-snapshot.gpg.key | sudo tee /etc/apt/trusted.gpg.d/apt.llvm.org.asc
-          echo -e deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-${{ matrix.llvm }} main | sudo tee /etc/apt/sources.list.d/llvm.list
-
-          sudo apt update
-          sudo apt -y install llvm-${{ matrix.llvm }}-dev
-          echo /usr/lib/llvm-${{ matrix.llvm }}/bin >> $GITHUB_PATH
+          wget https://ci-artifacts.rust-lang.org/rustc-builds/${{ env.LLVM_SHA }}/rust-dev-nightly-${{ env.LLVM_TARGET }}.tar.xz
+          tar -xpf rust-dev-nightly-${{ env.LLVM_TARGET }}.tar.xz --strip-components 1 -C /opt
+          echo /opt/rust-dev/bin >> $GITHUB_PATH
 
       - name: Restore LLVM
         if: matrix.llvm == 'source'
@@ -152,14 +142,14 @@ jobs:
       - uses: taiki-e/install-action@cargo-hack
 
       - name: Check
-        run: cargo hack check --feature-powerset --features llvm-sys/force-dynamic
+        run: cargo hack check --feature-powerset --features llvm-sys/force-static
 
       - name: Build
-        run: cargo hack build --feature-powerset --features llvm-sys/force-dynamic
+        run: cargo hack build --feature-powerset --features llvm-sys/force-static
 
       - name: Test
         if: matrix.rust == 'nightly'
-        run: cargo hack test --feature-powerset --features llvm-sys/force-dynamic
+        run: cargo hack test --feature-powerset --features llvm-sys/force-static
 
       - uses: actions/checkout@v4
         if: matrix.rust == 'nightly'
@@ -170,7 +160,7 @@ jobs:
 
       - name: Install
         if: matrix.rust == 'nightly'
-        run: cargo install --path . --no-default-features --features llvm-sys/force-dynamic
+        run: cargo install --path . --no-default-features --features llvm-sys/force-static
 
       # TODO: Remove this and run the integration tests on the local machine when they pass on 5.15.
       - name: Download debian kernels

.github/workflows/llvm.yml

@@ -16,7 +16,7 @@ jobs:
       - id: ls-remote
         run: |
           set -euxo pipefail
-          value=$(git ls-remote https://github.com/aya-rs/llvm-project.git refs/heads/rustc/18.0-2024-02-13 | cut -f1)
+          value=$(git ls-remote https://github.com/aya-rs/llvm-project.git refs/heads/rustc/19.1-2024-07-30 | cut -f1)
           echo "sha=$value" >> "$GITHUB_OUTPUT"
 
       - id: cache-key

.github/workflows/release.yml

@@ -3,27 +3,22 @@ name: Release
 on:
   release:
     types: [published]
+    
+env:
+  LLVM_SHA: 0b5eb7ba7bd796fb39c8bb6acd9ef6c140f28b65
+  LLVM_TARGET: x86_64-unknown-linux-musl
 
 jobs:
-  llvm:
-    uses: ./.github/workflows/llvm.yml
-
   upload-bins:
     # TODO: Build for macos someday.
     runs-on: ubuntu-22.04
-    needs: llvm
     steps:
-      - name: Restore LLVM
-        uses: actions/cache/restore@v4
-        with:
-          path: llvm-install
-          key: ${{ needs.llvm.outputs.cache-key }}
-          fail-on-cache-miss: true
-
-      - name: Add LLVM to PATH
+      - name: Install LLVM
         run: |
-          echo "${{ github.workspace }}/llvm-install/bin" >> $GITHUB_PATH
-          echo "$PATH"
+          set -euxo pipefail
+          wget https://ci-artifacts.rust-lang.org/rustc-builds/${{ env.LLVM_SHA }}/rust-dev-nightly-${{ env.LLVM_TARGET }}.tar.xz
+          tar -xpf rust-dev-nightly-${{ env.LLVM_TARGET }}.tar.xz --strip -C /opt
+          echo /opt/rust-dev/bin >> $GITHUB_PATH
 
       - uses: actions/checkout@v4
       - uses: Swatinem/rust-cache@v2

Cargo.lock

@@ -28,7 +28,7 @@ ar = { version = "0.9.0" }
 aya-rustc-llvm-proxy = { version = "0.9.2", optional = true }
 gimli = { version = "0.30.0" }
 libc = { version = "0.2.155" }
-llvm-sys = { features = ["disable-alltargets-init"], version = "180.0.0-rc2" }
+llvm-sys = { features = ["disable-alltargets-init"], version = "191.0.0-rc1" }
 log = { version = "0.4.22" }
 thiserror = { version = "1.0.61" }
 tracing = "0.1"

Cargo.toml

@@ -17,7 +17,7 @@ files with embedded bitcode (.o), optionally stored inside ar archives (.a).
 
 ## Installation
 
-The linker requires LLVM 18. It can use the same LLVM used by the rust compiler,
+The linker requires LLVM 19. It can use the same LLVM used by the rust compiler,
 or it can use an external LLVM installation.
 
 If your target is `aarch64-unknown-linux-gnu` (i.e. Linux on Apple Silicon) you 
@@ -33,14 +33,14 @@ cargo install bpf-linker
 
 ### Using external LLVM
 
-On Debian based distributions you need to install the `llvm-18-dev`, `libclang-18-dev`
-and `libpolly-18-dev` packages. If your distro doesn't have them you can get them
+On Debian based distributions you need to install the `llvm-19-dev`, `libclang-19-dev`
+and `libpolly-19-dev` packages. If your distro doesn't have them you can get them
 from the official LLVM repo at https://apt.llvm.org.
 
 On rpm based distribution you need the `llvm-devel` and `clang-devel` packages.
 If your distro doesn't have them you can get them from Fedora Rawhide.
 
-Once you have installed LLVM 18 you can install the linker running:
+Once you have installed LLVM 19 you can install the linker running:
 
 ```sh
 cargo install bpf-linker --no-default-features