Replace the musl submodule with a download script

Author: tgross35

.github/workflows/main.yaml

@@ -108,8 +108,6 @@ jobs:
     - name: Print runner information
       run: uname -a
     - uses: actions/checkout@v4
-      with:
-        submodules: true
     - name: Install Rust (rustup)
       shell: bash
       run: |
@@ -146,6 +144,10 @@ jobs:
       shell: bash
     - run: echo "RUST_COMPILER_RT_ROOT=$(realpath ./compiler-rt)" >> "$GITHUB_ENV"
       shell: bash
+      
+    - name: Download musl source
+      run: ./ci/update-musl.sh
+      shell: bash
 
     - name: Verify API list
       if: matrix.os == 'ubuntu-24.04'
@@ -182,15 +184,15 @@ jobs:
     timeout-minutes: 10
     steps:
     - uses: actions/checkout@v4
-      with:
-        submodules: true
     # Unlike rustfmt, stable clippy does not work on code with nightly features.
     - name: Install nightly `clippy`
       run: |
         rustup set profile minimal
         rustup default nightly
         rustup component add clippy
     - uses: Swatinem/rust-cache@v2
+    - name: Download musl source
+      run: ./ci/update-musl.sh
     - run: cargo clippy --workspace --all-targets
 
   benchmarks:
@@ -223,6 +225,8 @@ jobs:
     - uses: Swatinem/rust-cache@v2
       with:
         key: ${{ matrix.target }}
+    - name: Download musl source
+      run: ./ci/update-musl.sh
 
     - name: Run icount benchmarks
       env:

.gitignore

@@ -14,3 +14,6 @@ iai-home
 *.bk
 *.rs.bk
 .#*
+
+# Manually managed
+crates/musl-math-sys/musl

.gitmodules

@@ -0,0 +1,17 @@
+#!/bin/sh
+
+set -eux
+
+url=git://git.musl-libc.org/musl
+ref=c47ad25ea3b484e10326f933e927c0bc8cded3da
+dst=crates/musl-math-sys/musl
+
+if ! [ -d "$dst" ]; then
+    git clone "$url" "$dst" --single-branch --depth=1000
+fi
+
+git -C "$dst" fetch "$url" --depth=1
+git -C "$dst" checkout "$ref"
+
+
+