List available cmake generators

.github/workflows/list-cmake-generators.yml

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+name: List CMake Generators
+
+on:
+  pull_request:
+
+jobs:
+  list-generators:
+    if: false
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+          - ubuntu-24.04-arm
+          - windows-latest
+          - macos-latest
+          - macos-15-intel
+    runs-on: ${{ matrix.os }}
+    steps:
+      - name: List available CMake generators
+        shell: bash
+        run: |
+          OUTPUT=$(cmake -G 2>&1) || true
+          echo "$OUTPUT"
+          echo "## CMake Generators on ${{ matrix.os }}" >> "$GITHUB_STEP_SUMMARY"
+          echo '```' >> "$GITHUB_STEP_SUMMARY"
+          echo "$OUTPUT" >> "$GITHUB_STEP_SUMMARY"
+          echo '```' >> "$GITHUB_STEP_SUMMARY"
+
+      - name: List available MSVC toolsets
+        if: runner.os == 'Windows'
+        shell: pwsh
+        run: |
+          $vswhere = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
+          $installPath = & $vswhere -latest -property installationPath
+          $toolsetsPath = Join-Path $installPath "VC\Tools\MSVC"
+          Write-Host "Installed MSVC toolsets:"
+          Get-ChildItem $toolsetsPath -Directory | ForEach-Object { Write-Host "  $($_.Name)" }
+
+      - name: List compiler versions
+        if: runner.os != 'Windows'
+        run: |
+          echo "=== GCC ==="
+          gcc --version 2>/dev/null || echo "gcc not found"
+          echo ""
+          echo "=== Clang ==="
+          clang --version 2>/dev/null || echo "clang not found"

.github/workflows/test-clang-exception.yml

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+name: Test Clang exception linking
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: macos-15
+            cc: clang
+            cxx: clang++
+          - os: macos-15-intel
+            cc: clang
+            cxx: clang++
+          - os: macos-26
+            cc: clang
+            cxx: clang++
+          - os: macos-26-intel
+            cc: clang
+            cxx: clang++
+          - os: macos-15-intel
+            cc: /usr/bin/clang
+            cxx: /usr/bin/clang++
+          - os: macos-26-intel
+            cc: /usr/bin/clang
+            cxx: /usr/bin/clang++
+
+    runs-on: ${{ matrix.os }}
+    name: ${{ matrix.os }} (${{ matrix.cc }}/${{ matrix.cxx }})
+    env:
+      CC: ${{ matrix.cc }}
+      CXX: ${{ matrix.cxx }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Show system info
+        run: |
+          uname -m
+          sw_vers
+          which $CC
+          $CC --version
+          echo "---"
+          which $CXX
+          $CXX --version
+          echo "---"
+          echo "PATH=\"$PATH\""
+
+      - name: Configure
+        run: cmake -B build
+
+      - name: Build
+        run: cmake --build build --parallel
+
+      - name: Run
+        run: ./build/exception_test

CMakeLists.txt

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+cmake_minimum_required(VERSION 3.16)
+project(homebrew_clang_exception_test CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+add_executable(exception_test main.cpp)

main.cpp

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+#include <future>
+#include <iostream>
+#include <stdexcept>
+
+// This triggers __cxa_init_primary_exception / __from_native_exception_pointer
+// which are present in libc++ 18 headers but missing from Apple's system libc++.
+// Reproduces: https://github.com/llvm/llvm-project/issues/86077
+
+int main()
+{
+    std::promise<int> p;
+    auto f = p.get_future();
+
+    try {
+        p.set_exception(std::make_exception_ptr(std::runtime_error("test")));
+        f.get();
+    } catch (const std::runtime_error& e) {
+        std::cout << "Caught: " << e.what() << std::endl;
+    }
+
+    return 0;
+}