Detect Homebrew installations on macOS hosts

We provide immediate access to tools installed using the Homebrew
package manager as for the MSYS2 package manager.

build/org.eclipse.cdt.managedbuilder.gnu.ui/META-INF/MANIFEST.MF

@@ -2,17 +2,18 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.cdt.managedbuilder.gnu.ui; singleton:=true
-Bundle-Version: 8.7.300.qualifier
+Bundle-Version: 8.7.400.qualifier
 Bundle-Activator: org.eclipse.cdt.managedbuilder.gnu.ui.GnuUIPlugin
 Bundle-Vendor: %providerName
 Bundle-Localization: plugin
 Export-Package: org.eclipse.cdt.managedbuilder.gnu.cygwin,
+ org.eclipse.cdt.managedbuilder.gnu.macos;x-internal:=true,
  org.eclipse.cdt.managedbuilder.gnu.mingw;x-internal:=true,
  org.eclipse.cdt.managedbuilder.gnu.templates;x-internal:=true,
  org.eclipse.cdt.managedbuilder.gnu.ui
 Require-Bundle: org.eclipse.core.runtime;bundle-version="[3.33.0,4.0.0)",
  org.eclipse.cdt.managedbuilder.core;bundle-version="[9.7.100,10.0.0)",
- org.eclipse.cdt.core;bundle-version="[9.1.0,10.0.0)",
+ org.eclipse.cdt.core;bundle-version="[9.2.0,10.0.0)",
  org.eclipse.core.resources;bundle-version="[3.22.200,4)"
 Bundle-ActivationPolicy: lazy
 Bundle-RequiredExecutionEnvironment: JavaSE-17

build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <?eclipse version="3.0"?>
 <!--
-Copyright (c) 2005, 2024 Intel Corporation and others
+Copyright (c) 2005, 2025 Intel Corporation and others
 This program and the accompanying materials
 are made available under the terms of the Eclipse Public License 2.0
 which accompanies this distribution, and is available at
@@ -15,6 +15,7 @@ Contributors:
     John Dallaway - extend optimization options (#828)
     John Dallaway - add archiver other objects option (#653)
     John Dallaway - extend language standard options (#944)
+    John Dallaway - use macOS environment variable supplier (#1175)
 -->
 <plugin>
    <!-- Managed Make Builder Tool Specifications -->
@@ -2270,6 +2271,7 @@ Contributors:
       </toolChain>
       <toolChain
             archList="all"
+            configurationEnvironmentSupplier="org.eclipse.cdt.managedbuilder.gnu.macos.MacosEnvironmentVariableSupplier"
             id="cdt.managedbuild.toolchain.gnu.macosx.base"
             languageSettingsProviders="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser;org.eclipse.cdt.managedbuilder.core.GCCBuiltinSpecsDetector"
             name="%ToolChainName.Macosx"

build/org.eclipse.cdt.managedbuilder.gnu.ui/src/org/eclipse/cdt/managedbuilder/gnu/macos/MacosEnvironmentVariableSupplier.java

@@ -0,0 +1,64 @@
+/*******************************************************************************
+ * Copyright (c) 2025 John Dallaway and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     John Dallaway - Initial implementation (#1175)
+ *******************************************************************************/
+
+package org.eclipse.cdt.managedbuilder.gnu.macos;
+
+import org.eclipse.cdt.core.CCorePlugin;
+import org.eclipse.cdt.core.envvar.IEnvironmentVariable;
+import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
+import org.eclipse.cdt.internal.core.Homebrew;
+import org.eclipse.cdt.managedbuilder.core.IConfiguration;
+import org.eclipse.cdt.managedbuilder.envvar.IBuildEnvironmentVariable;
+import org.eclipse.cdt.managedbuilder.envvar.IConfigurationEnvironmentVariableSupplier;
+import org.eclipse.cdt.managedbuilder.envvar.IEnvironmentVariableProvider;
+import org.eclipse.cdt.managedbuilder.internal.envvar.BuildEnvVar;
+import org.eclipse.core.runtime.Path;
+
+/**
+ * Provides environment variables to support MBS builds using MacOS toolchains
+ *
+ * @noextend This class is not intended to be subclassed by clients.
+ */
+public class MacosEnvironmentVariableSupplier implements IConfigurationEnvironmentVariableSupplier {
+	private static final String ENV_PATH = "PATH"; //$NON-NLS-1$
+
+	@Override
+	public IBuildEnvironmentVariable getVariable(String variableName, IConfiguration configuration,
+			IEnvironmentVariableProvider provider) {
+		if (Homebrew.ENV_HOMEBREW_HOME.equals(variableName)) {
+			IEnvironmentVariable homebrewHomeVar = CCorePlugin.getDefault().getBuildEnvironmentManager()
+					.getVariable(Homebrew.ENV_HOMEBREW_HOME, (ICConfigurationDescription) null, false);
+			if (homebrewHomeVar == null) { // if HOMEBREW_HOME not already defined
+				String homebrewHome = Homebrew.getHomebrewHome();
+				if (homebrewHome == null) { // if Homebrew not installed
+					homebrewHome = ""; //$NON-NLS-1$
+				}
+				return new BuildEnvVar(Homebrew.ENV_HOMEBREW_HOME, new Path(homebrewHome).toOSString(),
+						IBuildEnvironmentVariable.ENVVAR_REPLACE);
+			}
+		} else if (variableName.equals(ENV_PATH)) {
+			String path = "${" + Homebrew.ENV_HOMEBREW_HOME + "}/bin"; //$NON-NLS-1$ //$NON-NLS-2$
+			return new BuildEnvVar(ENV_PATH, path, IBuildEnvironmentVariable.ENVVAR_PREPEND);
+		}
+		return null;
+	}
+
+	@Override
+	public IBuildEnvironmentVariable[] getVariables(IConfiguration configuration,
+			IEnvironmentVariableProvider provider) {
+		return new IBuildEnvironmentVariable[] { getVariable(Homebrew.ENV_HOMEBREW_HOME, configuration, provider),
+				getVariable(ENV_PATH, configuration, provider) };
+	}
+
+}

core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/Homebrew.java

@@ -0,0 +1,98 @@
+/*******************************************************************************
+ * Copyright (c) 2012, 2025 Andrew Gvozdev and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Andrew Gvozdev - Original MinGW API and implementation
+ *     John Dallaway  - Initial Homebrew implementation (#1175)
+ *******************************************************************************/
+package org.eclipse.cdt.internal.core;
+
+import java.util.Objects;
+
+import org.eclipse.cdt.core.CCorePlugin;
+import org.eclipse.cdt.core.envvar.IEnvironmentVariable;
+import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
+import org.eclipse.core.runtime.Path;
+import org.eclipse.core.runtime.Platform;
+
+/**
+ * A collection of Homebrew-related utility methods.
+ */
+public class Homebrew {
+	public static final String ENV_HOMEBREW_HOME = "HOMEBREW_HOME"; //$NON-NLS-1$
+
+	private static final String ENV_PATH = "PATH"; //$NON-NLS-1$
+
+	private static String envPathValueCached = null;
+	private static String envHomebrewHomeValueCached = null;
+	private static String homebrewLocation = null;
+	private static boolean isHomebrewLocationCached = false;
+
+	private static String findHomebrewRoot(String envPathValue, String envHomebrewHomeValue) {
+		// Check $HOMEBREW_HOME which overrides default locations
+		if (envHomebrewHomeValue != null && !envHomebrewHomeValue.isEmpty()) {
+			String homebrewPath = envHomebrewHomeValue;
+			if (installationExists(homebrewPath)) {
+				return homebrewPath;
+			}
+		}
+		String defaultHomebrewPath = getDefaultHomebrewPath();
+		if (installationExists(defaultHomebrewPath)) {
+			return defaultHomebrewPath;
+		}
+		return null;
+	}
+
+	private static boolean installationExists(String homebrewHomeDir) {
+		return new Path(homebrewHomeDir).append("bin").toFile().isDirectory(); //$NON-NLS-1$
+	}
+
+	private static String getDefaultHomebrewPath() {
+		final String os = Platform.getOS();
+		final String arch = Platform.getOSArch();
+		if (Platform.OS_MACOSX.equals(os)) {
+			if (Platform.ARCH_AARCH64.equals(arch)) {
+				return "/opt/homebrew"; //$NON-NLS-1$
+			} else if (Platform.ARCH_X86_64.equals(arch)) {
+				return "/usr/local"; //$NON-NLS-1$
+			}
+		} else if (Platform.OS_LINUX.equals(os) && Platform.ARCH_X86_64.equals(arch)) {
+			return "/home/linuxbrew/.linuxbrew"; //$NON-NLS-1$
+		}
+		return null;
+	}
+
+	/**
+	 * Find location where Homebrew is installed. Do not cache returned value.
+	 *
+	 * @return Homebrew installation path.
+	 */
+	public static String getHomebrewHome() {
+		IEnvironmentVariable varPath = CCorePlugin.getDefault().getBuildEnvironmentManager().getVariable(ENV_PATH,
+				(ICConfigurationDescription) null, true);
+		String envPathValue = varPath != null ? varPath.getValue() : null;
+		IEnvironmentVariable varHomebrewHome = CCorePlugin.getDefault().getBuildEnvironmentManager()
+				.getVariable(ENV_HOMEBREW_HOME, (ICConfigurationDescription) null, true);
+		String envHomebrewHomeValue = varHomebrewHome != null ? varHomebrewHome.getValue() : null;
+
+		if (isHomebrewLocationCached && Objects.equals(envPathValue, envPathValueCached)
+				&& Objects.equals(envHomebrewHomeValue, envHomebrewHomeValueCached)) {
+			return homebrewLocation;
+		}
+
+		homebrewLocation = findHomebrewRoot(envPathValue, envHomebrewHomeValue);
+		envPathValueCached = envPathValue;
+		envHomebrewHomeValueCached = envHomebrewHomeValue;
+		isHomebrewLocationCached = true;
+
+		return homebrewLocation;
+	}
+
+}

llvm/org.eclipse.cdt.managedbuilder.llvm.ui/META-INF/MANIFEST.MF

@@ -11,7 +11,7 @@ Require-Bundle: org.eclipse.ui;bundle-version="[3.207.200,4)",
  org.eclipse.core.resources;bundle-version="[3.22.200,4)",
  org.eclipse.cdt.managedbuilder.core;bundle-version="[9.7.100,10)",
  org.eclipse.cdt.managedbuilder.gnu.ui;bundle-version="[8.7.200,9)",
- org.eclipse.cdt.core;bundle-version="[9.1.0,10)"
+ org.eclipse.cdt.core;bundle-version="[9.2.0,10)"
 Bundle-RequiredExecutionEnvironment: JavaSE-17
 Bundle-ActivationPolicy: lazy
 Export-Package: org.eclipse.cdt.managedbuilder.llvm.makegen;

llvm/org.eclipse.cdt.managedbuilder.llvm.ui/src/org/eclipse/cdt/managedbuilder/llvm/ui/LlvmEnvironmentVariableSupplier.java

@@ -21,17 +21,20 @@ import java.io.File;
 import java.util.HashMap;
 import java.util.List;
 
+import org.eclipse.cdt.internal.core.Homebrew;
 import org.eclipse.cdt.internal.core.MinGW;
 import org.eclipse.cdt.managedbuilder.core.IConfiguration;
 import org.eclipse.cdt.managedbuilder.envvar.IBuildEnvironmentVariable;
 import org.eclipse.cdt.managedbuilder.envvar.IConfigurationEnvironmentVariableSupplier;
 import org.eclipse.cdt.managedbuilder.envvar.IEnvironmentVariableProvider;
 import org.eclipse.cdt.managedbuilder.gnu.cygwin.GnuCygwinConfigurationEnvironmentSupplier;
+import org.eclipse.cdt.managedbuilder.gnu.macos.MacosEnvironmentVariableSupplier;
 import org.eclipse.cdt.managedbuilder.gnu.mingw.MingwEnvironmentVariableSupplier;
 import org.eclipse.cdt.managedbuilder.llvm.ui.preferences.LlvmPreferenceStore;
 import org.eclipse.cdt.managedbuilder.llvm.util.Separators;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.Path;
+import org.eclipse.core.runtime.Platform;
 
 /**
  * Contains LLVM environment variables.
@@ -42,7 +45,7 @@ public class LlvmEnvironmentVariableSupplier implements IConfigurationEnvironmen
 	// toggle for preference changes
 	private static boolean preferencesChanged = true;
 	// LLVM environment variable data structure
-	private static HashMap<String, LlvmBuildEnvironmentVariable> llvmEnvironmentVariables = new HashMap<>(6);
+	private static HashMap<String, LlvmBuildEnvironmentVariable> llvmEnvironmentVariables = new HashMap<>(7);
 	// Environment variables for HashMap usage
 	private static final String ENV_VAR_NAME_LLVM_BIN = "LLVM_BIN_PATH"; //$NON-NLS-1$
 	private static final String ENV_VAR_NAME_LLVMINTERP = "LLVMINTERP"; //$NON-NLS-1$
@@ -52,10 +55,12 @@ public class LlvmEnvironmentVariableSupplier implements IConfigurationEnvironmen
 	private static final String ENV_VAR_NAME_LIBRARIES = "LIBRARIES"; //$NON-NLS-1$
 	private static final List<String> LLVM_BIN_SELECTION_TOOLS = List.of("llvm-ar", "clang"); //$NON-NLS-1$ //$NON-NLS-2$
 
+	private static boolean isInitialized = false;
+
 	/**
 	 * Initializes llvm environment variable paths from the system environment variables.
 	 */
-	public static void initializePaths() { //TODO: Is this actually called anywhere?
+	public static void initializePaths() {
 		// get bin path
 		String binPath = getBinPath();
 		// set LLVM bin path environment variable
@@ -69,16 +74,12 @@ public class LlvmEnvironmentVariableSupplier implements IConfigurationEnvironmen
 					// try to find mingw or cygwin path from PATH environment variable
 					IBuildEnvironmentVariable envPath = llvmEnvironmentVariables.get(ENV_VAR_NAME_PATH);
 					IBuildEnvironmentVariable mingwPath = null, cygwinPath = null;
-					// if path is empty
+					// try to find mingw path from MingwEnvironmentVariableSupplier
-					if (envPath == null) {
+					IConfigurationEnvironmentVariableSupplier mingwEnvironmentVariables = new MingwEnvironmentVariableSupplier();
-						// try to find mingw path from MingwEnvironmentVariableSupplier
+					mingwPath = mingwEnvironmentVariables.getVariable(ENV_VAR_NAME_PATH, null, null);
-						IConfigurationEnvironmentVariableSupplier mingwEnvironmentVariables = new MingwEnvironmentVariableSupplier();
+					// try to find cygwin path from GnuCygwinConfigurationEnvironmentSupplier
-						mingwPath = mingwEnvironmentVariables.getVariable(ENV_VAR_NAME_PATH, null, null);
+					IConfigurationEnvironmentVariableSupplier cygwinEnvironmentVariables = new GnuCygwinConfigurationEnvironmentSupplier();
-						// try to find cygwin path from GnuCygwinConfigurationEnvironmentSupplier
+					cygwinPath = cygwinEnvironmentVariables.getVariable(ENV_VAR_NAME_PATH, null, null);
-						IConfigurationEnvironmentVariableSupplier cygwinEnvironmentVariables = new GnuCygwinConfigurationEnvironmentSupplier();
-						cygwinPath = cygwinEnvironmentVariables.getVariable(ENV_VAR_NAME_PATH, null, null);
-
-					}
 					// if mingw found
 					if (mingwPath != null) {
 						//form full path
@@ -93,6 +94,14 @@ public class LlvmEnvironmentVariableSupplier implements IConfigurationEnvironmen
 					//TODO: Emit proper error message and enter it to Eclipse error log.
 					e.printStackTrace();
 				}
+			} else if (Platform.OS_MACOSX.equals(Platform.getOS())) {
+				// use MacosEnvironmentVariableSupplier to find PATH
+				IBuildEnvironmentVariable macosPath = new MacosEnvironmentVariableSupplier()
+						.getVariable(ENV_VAR_NAME_PATH, null, null);
+				if (macosPath != null) {
+					setLlvmEnvironmentVariable(Homebrew.ENV_HOMEBREW_HOME, Homebrew.getHomebrewHome());
+					pathStr += File.pathSeparator + macosPath.getValue();
+				}
 			}
 			//initialize environment variable cache values
 			setLlvmEnvironmentVariable(ENV_VAR_NAME_PATH, pathStr);
@@ -440,15 +449,24 @@ public class LlvmEnvironmentVariableSupplier implements IConfigurationEnvironmen
 		return ""; //$NON-NLS-1$
 	}
 
+	private static synchronized void init() {
+		if (!isInitialized) {
+			initializePaths();
+			isInitialized = true;
+		}
+	}
+
 	@Override
 	public IBuildEnvironmentVariable getVariable(String variableName, IConfiguration configuration,
 			IEnvironmentVariableProvider provider) {
+		init();
 		return llvmEnvironmentVariables.get(variableName);
 	}
 
 	@Override
 	public IBuildEnvironmentVariable[] getVariables(IConfiguration configuration,
 			IEnvironmentVariableProvider provider) {
+		init();
 		return llvmEnvironmentVariables.values().toArray(new IBuildEnvironmentVariable[0]);
 	}
 }