ci: migrate macOS 14 runners to macOS 15

.github/scripts/ci_changes.py

@@ -96,7 +96,9 @@ def classify(paths):
             selected.add("cpp_tidy")
         elif path.startswith("scripts/") and path.endswith(".sh"):
             selected.add("shell")
-            if path == "scripts/check-python.sh":
+            if path == "scripts/build-macos-openmp.sh":
+                selected.add("wheels")
+            elif path == "scripts/check-python.sh":
                 selected.add("python_quality")
             elif path == "scripts/check-tidy.sh":
                 selected.add("cpp_tidy")

.github/scripts/test_ci_changes.py

@@ -63,6 +63,7 @@ def test_language_specific_changes(self):
             },
             ".github/scripts/prepare_release.py": {"python_quality"},
             "scripts/check-python.sh": {"shell", "python_quality"},
+            "scripts/build-macos-openmp.sh": {"shell", "wheels"},
             "scripts/check-tidy.sh": {"shell", "cpp_tidy"},
             "scripts/check-format.sh": {"shell", "cpp_format"},
             "scripts/check-includes.sh": {"shell"},

.github/workflows/release.yml

@@ -197,7 +197,7 @@ jobs:
       !cancelled() && needs.prepare.result == 'success' &&
       needs.prepare.outputs.build == 'true' &&
       (needs.changes.result != 'success' || needs.changes.outputs.wheels == 'true')
-    runs-on: macos-14
+    runs-on: macos-15
     timeout-minutes: 90
     strategy:
       fail-fast: false

.github/workflows/test.yaml

@@ -256,7 +256,7 @@ jobs:
     name: Native Apple Silicon C++
     needs: changes
     if: ${{ !cancelled() && (needs.changes.result != 'success' || needs.changes.outputs.cpp == 'true') }}
-    runs-on: macos-14
+    runs-on: macos-15
     timeout-minutes: 45
     env:
       OMP_NUM_THREADS: "2"

pyproject.toml

@@ -53,11 +53,15 @@ test-environment = { RABITQ_TEST_WHEEL = "1", OMP_NUM_THREADS = "2" }
 
 [tool.cibuildwheel.macos]
 archs = ["arm64"]
-before-all = "brew install libomp"
-environment = { CMAKE_ARGS = "-DRABITQ_ENABLE_NATIVE_OPTIMIZATION=OFF -DOpenMP_ROOT=$(brew --prefix libomp)", MACOSX_DEPLOYMENT_TARGET = "14.0" }
+before-all = 'bash "{project}/scripts/build-macos-openmp.sh" "$RABITQ_OPENMP_PREFIX"'
 repair-wheel-command = "delocate-wheel --require-archs arm64 -w {dest_dir} -v {wheel}"
 test-environment = { RABITQ_TEST_WHEEL = "1", OMP_NUM_THREADS = "2" }
 
+[tool.cibuildwheel.macos.environment]
+MACOSX_DEPLOYMENT_TARGET = "14.0"
+RABITQ_OPENMP_PREFIX = "$(pwd)/build/wheel-openmp"
+CMAKE_ARGS = '-DRABITQ_ENABLE_NATIVE_OPTIMIZATION=OFF -DOpenMP_ROOT="$RABITQ_OPENMP_PREFIX" -DCMAKE_OSX_DEPLOYMENT_TARGET=$MACOSX_DEPLOYMENT_TARGET'
+
 [tool.cibuildwheel.windows]
 before-build = "python -m pip install delvewheel"
 repair-wheel-command = "delvewheel repair -w {dest_dir} {wheel}"

scripts/build-macos-openmp.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+readonly install_prefix="${1:?OpenMP install prefix is required}"
+readonly deployment_target="${MACOSX_DEPLOYMENT_TARGET:?macOS deployment target is required}"
+source_dir="$(mktemp -d)"
+readonly source_dir
+trap 'rm -rf "$source_dir"' EXIT
+
+# Homebrew bottles target the runner OS. Build its checksum-verified source
+# ourselves so the bundled runtime supports the wheel's older deployment target.
+brew fetch --build-from-source libomp
+tar -xf "$(brew --cache --build-from-source libomp)" \
+    -C "$source_dir" --strip-components=1
+cmake -S "$source_dir/runtimes" -B "$source_dir/build" \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DCMAKE_INSTALL_PREFIX="$install_prefix" \
+    -DCMAKE_OSX_ARCHITECTURES=arm64 \
+    -DCMAKE_OSX_DEPLOYMENT_TARGET="$deployment_target" \
+    -DLLVM_ENABLE_RUNTIMES=openmp \
+    -DOPENMP_INSTALL_LIBDIR=lib \
+    -DOPENMP_ENABLE_OMPT_TOOLS=OFF \
+    -DLIBOMP_INSTALL_ALIASES=OFF
+cmake --build "$source_dir/build" --parallel "$(sysctl -n hw.logicalcpu)"
+cmake --install "$source_dir/build"

tests/README.md

@@ -84,9 +84,13 @@ CMake excludes AVX source files on ARM64. Reference tests run through generic an
 NEON kernels; explicit AVX backend tests are guarded or skipped.
 
 For Python source builds, pass `-Ccmake.define.OpenMP_ROOT=<libomp-prefix>` as well
-as the native-optimization setting below. Release CI uses native `macos-14` runners,
+as the native-optimization setting below. Release CI uses native `macos-15` runners,
 builds CPython 3.11–3.14 ARM64 wheels, bundles OpenMP with delocate, then installs and
 runs the full Python suite for each wheel. The minimum wheel OS target is macOS 14.
+The wheel build compiles Homebrew's OpenMP source with that deployment target via
+`scripts/build-macos-openmp.sh`; the runner's prebuilt OpenMP bottle may require a
+newer macOS. The installed-wheel check verifies both the extension and bundled
+runtime support macOS 14.
 Set `RABITQ_TEST_WHEEL=1` when testing a repaired wheel locally to also check its
 ARM64 extension and bundled OpenMP loader path.
 

tests/python/test_wheel_macos.py

@@ -2,6 +2,7 @@
 
 import os
 import platform
+import re
 import subprocess
 from pathlib import Path
 
@@ -37,3 +38,10 @@ def test_native_arm64_wheel_bundles_openmp():
         subprocess.check_output(["lipo", "-archs", str(runtime)], text=True).strip()
         == "arm64"
     )
+    for binary in (path, runtime):
+        load_commands = subprocess.check_output(["otool", "-l", str(binary)], text=True)
+        minimum_versions = re.findall(r"\bminos (\d+)\.(\d+)", load_commands)
+        assert minimum_versions, load_commands
+        assert all(
+            (int(major), int(minor)) <= (14, 0) for major, minor in minimum_versions
+        ), f"{binary} requires macOS newer than 14.0: {minimum_versions}"