CI: try to speedup by avoiding unnecessary installs (#3144)

* Start removing non-apt deps

GH images come with baked-in software that doesn't
come from apt, getting the apt version will just
slow down CI since the baked in version will be
used anyway.

* Do not install llvm-X if already there

* Do not remove old llvm-X

Est-ce qu'ils nous derangent ?

* default llvm install is missing stuff

* CLang is already baked-in

* Set installed clang as default

* Move ARM deps to qemu fuzzers

.github/workflows/build_and_test.yml

@@ -171,8 +171,6 @@ jobs:
     runs-on: ubuntu-24.04
     needs: ubuntu
     steps:
-      - name: Install curl
-        run: sudo apt-get update && sudo apt-get install clang
       - uses: dtolnay/rust-toolchain@stable
       - uses: actions/checkout@v4
       - uses: Swatinem/rust-cache@v2
@@ -186,7 +184,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Install deps
-        run: sudo apt-get update && sudo apt-get install -y lsb-release wget software-properties-common gnupg ninja-build python3-dev python3-pip python3-venv libz3-dev
+        run: sudo apt-get update && sudo apt-get install -y lsb-release wget software-properties-common gnupg libz3-dev
       - name: Install maturin
         run: cargo install --locked maturin
       - uses: actions/checkout@v4
@@ -610,8 +608,6 @@ jobs:
   android:
     runs-on: ubuntu-24.04
     steps:
-      - name: Install curl
-        run: sudo apt-get update && sudo apt-get install clang
       - uses: dtolnay/rust-toolchain@stable
       - uses: nttld/setup-ndk@v1
         with:

.github/workflows/qemu-fuzzer-tester-prepare/action.yml

@@ -5,7 +5,10 @@ runs:
   steps:
     - name: Install QEMU deps
       shell: bash
-      run: apt-get update && apt-get install -y qemu-utils sudo python3-msgpack python3-jinja2 curl python3-dev
+      run: |
+        apt-get update 
+        apt-get install -y qemu-utils sudo python3-msgpack python3-jinja2 curl python3-dev gcc-arm-none-eabi \
+          gcc-arm-linux-gnueabi g++-arm-linux-gnueabi
     - uses: dtolnay/rust-toolchain@stable
     - name: enable mult-thread for `make`
       shell: bash

.github/workflows/ubuntu-prepare/action.yml

@@ -5,7 +5,10 @@ runs:
   steps:
     - name: Install and cache deps
       shell: bash
-      run: sudo apt-get update && sudo apt-get install -y curl lsb-release wget software-properties-common gnupg ninja-build shellcheck pax-utils nasm libsqlite3-dev libc6-dev libgtk-3-dev gcc g++ gcc-arm-none-eabi gcc-arm-linux-gnueabi g++-arm-linux-gnueabi libslirp-dev libz3-dev build-essential
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y curl lsb-release wget software-properties-common gnupg shellcheck pax-utils \
+          nasm libsqlite3-dev libc6-dev libgtk-3-dev gcc g++ libslirp-dev libz3-dev build-essential \
     - uses: dtolnay/rust-toolchain@stable
     - name: install just
       uses: extractions/setup-just@v2
@@ -17,9 +20,6 @@ runs:
     - name: Add nightly clippy
       shell: bash
       run: rustup toolchain install nightly --component clippy --allow-downgrade
-    - name: Remove existing clang and LLVM
-      shell: bash
-      run: sudo apt-get purge -y *llvm* *clang* lld* lldb* opt*
     - name: Install cargo-hack
       shell: bash
       run: curl -LsSf https://github.com/taiki-e/cargo-hack/releases/latest/download/cargo-hack-x86_64-unknown-linux-gnu.tar.gz | tar xzf - -C ~/.cargo/bin
@@ -29,12 +29,13 @@ runs:
     - name: Default to nightly
       shell: bash
       run: rustup default nightly
-    - name: Add LLVM in sources list
+    - name: Install LLVM
       shell: bash
       run: |
         wget https://apt.llvm.org/llvm.sh
         chmod +x llvm.sh
         sudo ./llvm.sh ${{env.MAIN_LLVM_VERSION}} all
+        sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-${{env.MAIN_LLVM_VERSION}} 200
     - name: Symlink Headers
       shell: bash
       run: sudo ln -s /usr/include/asm-generic /usr/include/asm