### Eclipse Workspace Patch 1.0
#P org.eclipse.pde.core
Index: src/org/eclipse/pde/internal/core/builders/BundleErrorReporter.java
===================================================================
RCS file: /cvsroot/eclipse/pde/ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/builders/BundleErrorReporter.java,v
retrieving revision 1.68
diff -u -r1.68 BundleErrorReporter.java
--- src/org/eclipse/pde/internal/core/builders/BundleErrorReporter.java	14 Oct 2008 16:08:45 -0000	1.68
+++ src/org/eclipse/pde/internal/core/builders/BundleErrorReporter.java	27 Feb 2009 16:20:37 -0000
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2008 IBM Corporation and others.
+ * Copyright (c) 2000, 2009 IBM Corporation 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
@@ -7,7 +7,7 @@
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
- *     Code 9 Corporation - on going enhancements and maintenance
+ *     EclipseSource Corporation - ongoing enhancements and maintenance
  *     Brock Janiczak <brockj@tpg.com.au> - bug 169373
  *     Gary Duprex <Gary.Duprex@aspectstools.com> - bug 150225
  *     Bartosz Michalik <bartosz.michalik@gmail.com> - bug 209432, 214156
@@ -170,7 +170,7 @@
 		IPluginBase base = fModel.getPluginBase();
 		// must check the existence of plugin.xml file instead of using IPluginBase because if the bundle is not a singleton,
 		// it won't be registered with the extension registry and will always return 0 when querying extensions/extension points
-		boolean hasExtensions = base != null && fProject.findMember(ICoreConstants.PLUGIN_PATH) != null;
+		boolean hasExtensions = base != null && (fProject.findMember(ICoreConstants.PLUGIN_PATH) != null || fProject.findMember(ICoreConstants.FRAGMENT_PATH) != null);
 
 		if (hasExtensions) {
 			if (TargetPlatformHelper.getTargetVersion() >= 3.1) {
@@ -193,6 +193,16 @@
 				report(message, header.getLineNumber() + 1, CompilerFlags.ERROR, PDEMarkerFactory.M_SINGLETON_ATT_NOT_SET, PDEMarkerFactory.CAT_OTHER);
 				return;
 			}
+			// if we're a fragment, ensure the host is a singleton
+			if (fModel.isFragmentModel()) {
+				IHeader fHeader = getHeader(Constants.FRAGMENT_HOST);
+				if (fHeader == null)
+					return;
+				String host = fHeader.getValue();
+				if (host != null) {
+					// TODO call the PluginRegistry to find the host model, see if it has the singleton attribute marked
+				}
+			}
 		}
 
 		if (fOsgiR4) {