Add support to ubuntu-22.04 (rust-lang#2105)

- Create a ubuntu-22.04 scripts symlink folder.
- Change the cbcm installation to pick which CBMC distro to use depending on the ubuntu major version. So Ubuntu-22.04 will install the version for 20.04.
- Add ubuntu-22.04 to our CI.

Author: celinval

.github/workflows/cbmc-latest.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [macos-11, ubuntu-18.04, ubuntu-20.04]
+        os: [macos-11, ubuntu-18.04, ubuntu-20.04, ubuntu-22.04]
     steps:
       - name: Checkout Kani
         uses: actions/checkout@v3

.github/workflows/kani.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [macos-11, ubuntu-18.04, ubuntu-20.04]
+        os: [macos-11, ubuntu-18.04, ubuntu-20.04, ubuntu-22.04]
     steps:
       - name: Checkout Kani
         uses: actions/checkout@v3

.github/workflows/slow-tests.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [macos-11, ubuntu-18.04, ubuntu-20.04]
+        os: [macos-11, ubuntu-18.04, ubuntu-20.04, ubuntu-22.04]
     steps:
       - name: Checkout Kani
         uses: actions/checkout@v3

docs/src/build-from-source.md

@@ -18,7 +18,7 @@ Kani has been tested in [Ubuntu](#install-dependencies-on-ubuntu) and [macOS](##
 
 ### Install dependencies on Ubuntu
 
-Support is available for Ubuntu 18.04 and 20.04.
+Support is available for Ubuntu 18.04, 20.04 and 22.04.
 The simplest way to install dependencies (especially if you're using a fresh VM)
 is following our CI scripts:
 

scripts/setup/ubuntu-22.04

@@ -0,0 +1 @@
+ubuntu

scripts/setup/ubuntu/install_cbmc.sh

@@ -13,7 +13,17 @@ if [ -z "${CBMC_VERSION:-}" ]; then
 fi
 
 UBUNTU_VERSION=$(lsb_release -rs)
-FILE="ubuntu-${UBUNTU_VERSION}-cbmc-${CBMC_VERSION}-Linux.deb"
+MAJOR=${UBUNTU_VERSION%.*}
+
+# CBMC currently only release a 18.04 and a 20.04 versions.
+if [[ "${MAJOR}" -le "18" ]]
+then
+    MIRROR_VERSION="18.04"
+else
+    MIRROR_VERSION="20.04"
+fi
+
+FILE="ubuntu-${MIRROR_VERSION}-cbmc-${CBMC_VERSION}-Linux.deb"
 URL="https://github.com/diffblue/cbmc/releases/download/cbmc-${CBMC_VERSION}/$FILE"
 
 set -x