Switch MacOS CI jobs to macos-13 (#2987)

This is currently marked "Beta". Switching is an attempt to address the
memory allocation failures.

.github/workflows/cbmc-latest.yml

@@ -19,7 +19,7 @@ jobs:
  runs-on: ${{ matrix.os }}
  strategy:
  matrix:
- os: [macos-12, ubuntu-20.04, ubuntu-22.04]
+ os: [macos-13, ubuntu-20.04, ubuntu-22.04]
  steps:
  - name: Checkout Kani under "kani"
  uses: actions/checkout@v4

.github/workflows/kani.yml

@@ -17,7 +17,7 @@ jobs:
  runs-on: ${{ matrix.os }}
  strategy:
  matrix:
- os: [macos-12, ubuntu-20.04, ubuntu-22.04]
+ os: [macos-13, ubuntu-20.04, ubuntu-22.04]
  steps:
  - name: Checkout Kani
  uses: actions/checkout@v4

.github/workflows/release.yml

@@ -20,7 +20,7 @@ env:
 jobs:
  build_bundle_macos:
  name: BuildBundle-MacOs
- runs-on: macos-12
+ runs-on: macos-13
  permissions:
  contents: write
  outputs:
@@ -35,13 +35,13 @@ jobs:
  - name: Setup Kani Dependencies
  uses: ./.github/actions/setup
  with:
- os: macos-12
+ os: macos-13
 
  - name: Build bundle
  id: bundle
  uses: ./.github/actions/build-bundle
  with:
- os: macos-12
+ os: macos-13
  arch: x86_64-apple-darwin
 
  build_bundle_linux:
@@ -106,11 +106,11 @@ jobs:
  needs: [build_bundle_macos, build_bundle_linux]
  strategy:
  matrix:
- os: [macos-12, ubuntu-20.04, ubuntu-22.04]
+ os: [macos-13, ubuntu-20.04, ubuntu-22.04]
  include:
  # Stores the output of the previous job conditional to the OS
  - prev_job: ${{ needs.build_bundle_linux.outputs }}
- - os: macos-12
+ - os: macos-13
  prev_job: ${{ needs.build_bundle_macos.outputs }}
  runs-on: ${{ matrix.os }}
  steps:

.github/workflows/slow-tests.yml

@@ -18,7 +18,7 @@ jobs:
  runs-on: ${{ matrix.os }}
  strategy:
  matrix:
- os: [macos-12, ubuntu-20.04, ubuntu-22.04]
+ os: [macos-13, ubuntu-20.04, ubuntu-22.04]
  steps:
  - name: Checkout Kani
  uses: actions/checkout@v4

scripts/setup/macos-13

@@ -0,0 +1 @@
+macos

scripts/setup/macos/install_viewer.sh

@@ -18,5 +18,8 @@ set -x
 
 # brew doesn't recognize specific versions of viewer
 # Build from source, since there's only a macos-12 bottle which doesn't seem to work.
+# Install Python 3.12 first while ignoring errors: the system may provide this
+# version, which will hinder brew from installing symlinks
+brew install python@3.12 || true
 brew install -s aws/tap/cbmc-viewer
 echo "Installed: $(cbmc-viewer --version)"