Add homebrew llvm version toolchain support

config/env.ini

@@ -134,6 +134,8 @@ OPENSSLDIR=""
 ; build target: macho or macho (possibly we could support macho-universal in the future)
 ; Currently we do not support universal and cross-compilation for macOS.
 SPC_TARGET=native-macos
+; Whether to use brew version of llvm or system version (valid options: 'system', 'brew', default: 'system')
+SPC_USE_LLVM=system
 ; compiler environments (default value is defined by selected toolchain)
 CC=${SPC_DEFAULT_CC}
 CXX=${SPC_DEFAULT_CXX}

src/StaticPHP/Doctor/Item/MacOSToolCheck.php

@@ -7,6 +7,7 @@ namespace StaticPHP\Doctor\Item;
 use StaticPHP\Attribute\Doctor\CheckItem;
 use StaticPHP\Attribute\Doctor\FixItem;
 use StaticPHP\Doctor\CheckResult;
+use StaticPHP\Runtime\SystemTarget;
 use StaticPHP\Util\System\MacOSUtil;
 
 class MacOSToolCheck
@@ -58,6 +59,20 @@ class MacOSToolCheck
         return CheckResult::ok();
     }
 
+    #[CheckItem('if homebrew llvm are installed', limit_os: 'Darwin')]
+    public function checkBrewLLVM(): ?CheckResult
+    {
+        if (getenv('SPC_USE_LLVM') === 'brew') {
+            $homebrew_prefix = getenv('HOMEBREW_PREFIX') ?: (SystemTarget::getTargetArch() === 'aarch64' ? '/opt/homebrew' : '/usr/local/homebrew');
+
+            if (MacOSUtil::findCommand('clang', ["{$homebrew_prefix}/opt/llvm/bin"]) === null) {
+                return CheckResult::fail('Homebrew llvm is not installed', 'brew', ['missing' => ['llvm']]);
+            }
+            return CheckResult::ok();
+        }
+        return null;
+    }
+
     #[CheckItem('if bison version is 3.0 or later', limit_os: 'Darwin')]
     public function checkBisonVersion(array $command_path = []): ?CheckResult
     {

src/StaticPHP/Toolchain/ClangBrewToolchain.php

@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace StaticPHP\Toolchain;
+
+use StaticPHP\Runtime\SystemTarget;
+use StaticPHP\Util\GlobalEnvManager;
+
+class ClangBrewToolchain extends ClangNativeToolchain
+{
+    public function initEnv(): void
+    {
+        $homebrew_prefix = getenv('HOMEBREW_PREFIX') ?: (SystemTarget::getTargetArch() === 'aarch64' ? '/opt/homebrew' : '/usr/local/homebrew');
+        GlobalEnvManager::putenv("SPC_DEFAULT_CC={$homebrew_prefix}/opt/llvm/bin/clang");
+        GlobalEnvManager::putenv("SPC_DEFAULT_CXX={$homebrew_prefix}/opt/llvm/bin/clang++");
+        GlobalEnvManager::putenv("SPC_DEFAULT_AR={$homebrew_prefix}/opt/llvm/bin/llvm-ar");
+        GlobalEnvManager::putenv('SPC_DEFAULT_LD=ld');
+        GlobalEnvManager::addPathIfNotExists("{$homebrew_prefix}/opt/llvm/bin");
+    }
+}

src/StaticPHP/Toolchain/ToolchainManager.php

@@ -39,7 +39,10 @@ class ToolchainManager
         return match (PHP_OS_FAMILY) {
             'Linux' => ZigToolchain::class,
             'Windows' => MSVCToolchain::class,
-            'Darwin' => ClangNativeToolchain::class,
+            'Darwin' => match (getenv('SPC_USE_LLVM') ?: 'system') {
+                'brew' => ClangBrewToolchain::class,
+                default => ClangNativeToolchain::class,
+            },
             default => throw new WrongUsageException('Unsupported OS family: ' . PHP_OS_FAMILY),
         };
     }