diff --git a/build/org.eclipse.cdt.managedbuilder.core/META-INF/MANIFEST.MF b/build/org.eclipse.cdt.managedbuilder.core/META-INF/MANIFEST.MF
index 8a343cf2fcb..05b5bb3796b 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/META-INF/MANIFEST.MF
+++ b/build/org.eclipse.cdt.managedbuilder.core/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.cdt.managedbuilder.core; singleton:=true
-Bundle-Version: 8.4.0.qualifier
+Bundle-Version: 8.5.0.qualifier
 Bundle-Activator: org.eclipse.cdt.managedbuilder.core.ManagedBuilderCorePlugin
 Bundle-Vendor: %providerName
 Bundle-Localization: plugin
diff --git a/build/org.eclipse.cdt.managedbuilder.core/schema/buildDefinitions.exsd b/build/org.eclipse.cdt.managedbuilder.core/schema/buildDefinitions.exsd
index 5a0b969d40b..cc87103afef 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/schema/buildDefinitions.exsd
+++ b/build/org.eclipse.cdt.managedbuilder.core/schema/buildDefinitions.exsd
@@ -1363,6 +1363,16 @@ Additional special types exist to flag options of special relevance to the build
                </documentation>
             </annotation>
          </attribute>
+         <attribute name="defaultValueGenerator" type="string">
+            <annotation>
+               <documentation>
+                  Optional class which can be used to override the default value for an option. This class must implement the IOptionDefaultValueGenerator interface.  If no generator is specified then the &apos;defaultValue&apos; attribute is used to generate the option&apos;s default value.
+               </documentation>
+               <appInfo>
+                  <meta.attribute kind="java" basedOn=":org.eclipse.cdt.managedbuilder.core.IOptionDefaultValueGenerator"/>
+               </appInfo>
+            </annotation>
+         </attribute>
          <attribute name="command" type="string">
             <annotation>
                <documentation>
diff --git a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOption.java b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOption.java
index fc659b185c0..9128abbf672 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOption.java
+++ b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOption.java
@@ -11,6 +11,7 @@
  *     James Blackburn (Broadcom Corp.)
  *     Petri Tuononen - [321040] Get Library Search Paths
  *     Baltasar Belyavsky (Texas Instruments) - [279633] Custom command-generator support
+ *     cartu38 opendev (STMicroelectronics) - [514385] Custom defaultValue-generator support
  *******************************************************************************/
 package org.eclipse.cdt.managedbuilder.core;
 
@@ -107,6 +108,10 @@ public interface IOption extends IBuildObject {
 	public static final String TOOL_TIP = "tip"; //$NON-NLS-1$
 	public static final String CONTEXT_ID = "contextId"; //$NON-NLS-1$
 	public static final String DEFAULT_VALUE = "defaultValue"; //$NON-NLS-1$
+	/**
+	 * @since 8.5
+	 */
+	public static final String DEFAULTVALUE_GENERATOR = "defaultValueGenerator"; //$NON-NLS-1$
 	public static final String ENUM_VALUE = "enumeratedOptionValue"; //$NON-NLS-1$
 	/**
 	 * @since 8.1
@@ -482,6 +487,12 @@ public interface IOption extends IBuildObject {
 	 */
 	public Object getDefaultValue();
 
+	/**
+	 * @return an instance of the class that overrides the default defaultValue generation for the option
+	 * @since 8.5
+	 */
+	public IOptionDefaultValueGenerator getDefaultValueGenerator();
+
 	/**
 	 * @return the type for the value of the option.
 	 */
diff --git a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOptionDefaultValueGenerator.java b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOptionDefaultValueGenerator.java
new file mode 100644
index 00000000000..e2efab913fe
--- /dev/null
+++ b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/core/IOptionDefaultValueGenerator.java
@@ -0,0 +1,34 @@
+/*******************************************************************************
+ * Copyright (c) 2017 STMicroelectronics and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     cartu38 opendev (STMicroelectronics) - [514385] Custom defaultValue-generator support
+ *******************************************************************************/
+
+package org.eclipse.cdt.managedbuilder.core;
+
+/**
+ * This interface can be implemented by clients to contribute custom defaultValue-generator for a
+ * build-option.
+ * 
+ * The custom defaultValue-generator class should be referenced in the <option>/defaultValueGenerator
+ * attribute of the org.eclipse.cdt.managedbuilder.core.buildDefinitions extension-point.
+ * 
+ * @since 8.5
+ */
+public interface IOptionDefaultValueGenerator {
+	/**
+	 * Generate the defaultValue for the given option.
+	 * 
+	 * @param option
+	 *            the underlying build-option
+	 * @return the generated build-option defaultValue. May return {@code null} to fall back to the default
+	 *         defaultValue generation logic.
+	 */
+	Object generateDefaultValue(IOption option);
+
+}
diff --git a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/FolderInfo.java b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/FolderInfo.java
index a35ec0e728b..95b03a0e0a3 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/FolderInfo.java
+++ b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/FolderInfo.java
@@ -7,6 +7,7 @@
  *
  * Contributors:
  * Intel Corporation - Initial API and implementation
+ * cartu38 opendev (STMicroelectronics) - [514385] Custom defaultValue-generator support
  *******************************************************************************/
 package org.eclipse.cdt.managedbuilder.internal.core;
 
@@ -1334,6 +1335,11 @@ public class FolderInfo extends ResourceInfo implements IFolderInfo {
 		IOption[] opts = holder.getOptions();
 		for (IOption opt : opts) {
 			Object val = opt.getDefaultValue();
+
+			if (opt.getDefaultValueGenerator() != null) {
+				val = opt.getDefaultValueGenerator().generateDefaultValue(opt);
+			}
+
 			if (val instanceof Boolean) {
 				ManagedBuildManager.setOption(toolChain.getParent(), holder, opt, (Boolean)val);
 			} else if (val instanceof String[]) {
diff --git a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/Option.java b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/Option.java
index 73939e53ae4..1a2ee15301a 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/Option.java
+++ b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/Option.java
@@ -10,6 +10,7 @@
  *     ARM Ltd. - basic tooltip support
  *     Petri Tuononen - [321040] Get Library Search Paths
  *     Baltasar Belyavsky (Texas Instruments) - [279633] Custom command-generator support
+ *     cartu38 opendev (STMicroelectronics) - [514385] Custom defaultValue-generator support
  *******************************************************************************/
 package org.eclipse.cdt.managedbuilder.internal.core;
 
@@ -32,6 +33,7 @@ import org.eclipse.cdt.managedbuilder.core.IOption;
 import org.eclipse.cdt.managedbuilder.core.IOptionApplicability;
 import org.eclipse.cdt.managedbuilder.core.IOptionCategory;
 import org.eclipse.cdt.managedbuilder.core.IOptionCommandGenerator;
+import org.eclipse.cdt.managedbuilder.core.IOptionDefaultValueGenerator;
 import org.eclipse.cdt.managedbuilder.core.IProjectType;
 import org.eclipse.cdt.managedbuilder.core.ITool;
 import org.eclipse.cdt.managedbuilder.core.IToolChain;
@@ -79,6 +81,8 @@ public class Option extends BuildObject implements IOption, IBuildPropertiesRest
 	private Map<String, String> namesMap;
 	private Object value;
 	private Object defaultValue;
+	private IConfigurationElement defaultValueGeneratorElement;
+	private IOptionDefaultValueGenerator defaultValueGenerator;
 	private Integer valueType;
 	private Boolean isAbstract;
 	private Integer resourceFilter;
@@ -303,6 +307,9 @@ public class Option extends BuildObject implements IOption, IBuildPropertiesRest
 
 		category = option.category;
 
+		defaultValueGeneratorElement = option.defaultValueGeneratorElement;
+		defaultValueGenerator = option.defaultValueGenerator;
+
 		commandGeneratorElement = option.commandGeneratorElement;
 		commandGenerator = option.commandGenerator;
 
@@ -366,6 +373,12 @@ public class Option extends BuildObject implements IOption, IBuildPropertiesRest
 			isAbstract = Boolean.parseBoolean(isAbs);
 		}
 
+		// Get the defaultValue-generator, if any
+		String defaultValueGeneratorStr = element.getAttribute(DEFAULTVALUE_GENERATOR);
+		if (defaultValueGeneratorStr != null && element instanceof DefaultManagedConfigElement) {
+			defaultValueGeneratorElement = ((DefaultManagedConfigElement) element).getConfigurationElement();
+		}
+
 		// Get the command defined for the option
 		command = SafeStringInterner.safeIntern(element.getAttribute(COMMAND));
 
@@ -1228,6 +1241,26 @@ public class Option extends BuildObject implements IOption, IBuildPropertiesRest
 		return category;
 	}
 
+	@Override
+	public IOptionDefaultValueGenerator getDefaultValueGenerator() {
+		if (defaultValueGenerator == null) {
+			if (defaultValueGeneratorElement != null) {
+				try {
+					if (defaultValueGeneratorElement.getAttribute(DEFAULTVALUE_GENERATOR) != null) {
+						defaultValueGenerator = (IOptionDefaultValueGenerator) defaultValueGeneratorElement
+								.createExecutableExtension(DEFAULTVALUE_GENERATOR);
+					}
+				} catch (CoreException e) {
+					ManagedBuilderCorePlugin.log(e);
+				}
+			} else if (superClass != null) {
+				defaultValueGenerator = superClass.getDefaultValueGenerator();
+			}
+		}
+
+		return defaultValueGenerator;
+	}
+
 	@Override
 	public String getCommand() {
 		if (command == null) {
diff --git a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/OptionReference.java b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/OptionReference.java
index e706bd05a6c..b0bfe1200c9 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/OptionReference.java
+++ b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/OptionReference.java
@@ -10,6 +10,7 @@
  *     ARM Ltd. - basic tooltip support
  *     Petri Tuononen - [321040] Get Library Search Paths
  *     Baltasar Belyavsky (Texas Instruments) - [279633] Custom command-generator support
+ *     cartu38 opendev (STMicroelectronics) - [514385] Custom defaultValue-generator support
  *******************************************************************************/
 package org.eclipse.cdt.managedbuilder.internal.core;
 
@@ -27,6 +28,7 @@ import org.eclipse.cdt.managedbuilder.core.IOption;
 import org.eclipse.cdt.managedbuilder.core.IOptionApplicability;
 import org.eclipse.cdt.managedbuilder.core.IOptionCategory;
 import org.eclipse.cdt.managedbuilder.core.IOptionCommandGenerator;
+import org.eclipse.cdt.managedbuilder.core.IOptionDefaultValueGenerator;
 import org.eclipse.cdt.managedbuilder.core.ManagedBuildManager;
 import org.eclipse.cdt.managedbuilder.core.OptionStringValue;
 import org.eclipse.cdt.managedbuilder.macros.IOptionContextData;
@@ -765,6 +767,11 @@ public class OptionReference implements IOption {
 		return value;
 	}
 
+	@Override
+	public IOptionDefaultValueGenerator getDefaultValueGenerator() {
+		return option.getDefaultValueGenerator();
+	}
+
 	@Override
 	public void setDefaultValue(Object v) {
 	}