diff --git a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.java b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.java
index aca82d55614..1832851d0f3 100644
--- a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.java
+++ b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.java
@@ -286,6 +286,10 @@ public class Messages extends NLS {
 	public static String WizardDefaultsTab_0;
 	public static String WizardDefaultsTab_1;
 	public static String RefreshPolicyTab_resourcesTreeLabel;
+	public static String BuilderSettingsTab_23;
+	public static String BuilderSettingsTab_24;
+	public static String BuilderSettingsTab_25;
+	public static String BuilderSettingsTab_26;
 
 	static {
 		// Initialize resource bundle.
diff --git a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.properties b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.properties
index d10945519a4..65a03e53d28 100644
--- a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.properties
+++ b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/internal/ui/Messages.properties
@@ -41,6 +41,10 @@ BuilderSettingsTab_19=Build (Incremental build)
 BuilderSettingsTab_20=Clean
 BuilderSettingsTab_21=Build location
 BuilderSettingsTab_22=Build &directory:
+BuilderSettingsTab_23=Confirm toolchain change
+BuilderSettingsTab_24=Changing toolchain will reset all tool settings to default values. Existing settings will be unrecoverable.
+BuilderSettingsTab_25=Continue
+BuilderSettingsTab_26=Cancel
 BuilderSettingsTab_Configure_Build_Arguments_In_the_Behavior_tab=Configure build arguments in the Behavior tab.
 BuildStepsTab_0=Command:
 BuildStepsTab_1=Description:
diff --git a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/ToolChainEditTab.java b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/ToolChainEditTab.java
index b1b3383c375..96539cfe806 100644
--- a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/ToolChainEditTab.java
+++ b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/ToolChainEditTab.java
@@ -44,6 +44,7 @@ import org.eclipse.cdt.managedbuilder.tcmodification.IToolModification;
 import org.eclipse.cdt.ui.CDTSharedImages;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IStatus;
+import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.osgi.util.NLS;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
@@ -113,7 +114,14 @@ public class ToolChainEditTab extends AbstractCBuildPropertyTab {
 		c_toolchain.addSelectionListener(new SelectionAdapter() {
 			@Override
 			public void widgetSelected(SelectionEvent e) {
-				modifyToolchain();
+				if (MessageDialog.open(MessageDialog.WARNING, c_toolchain.getShell(), Messages.BuilderSettingsTab_23,
+						Messages.BuilderSettingsTab_24, SWT.NONE, Messages.BuilderSettingsTab_25,
+						Messages.BuilderSettingsTab_26) == MessageDialog.OK) {
+					modifyToolchain();
+				} else {
+					e.doit = false;
+					fillToolChainCombo();
+				}
 			}
 		});
 		c_toolchain.setEnabled(!page.isForFile());