Qt - cleanup build cases. Add method to GDBLaunch.

Clean up cases when Qt installs aren't registered for a given
config. Fix bug on first scanner info request in build config.
Clean up the Qt Run launch delegate in extension.

Also added a method to GDBLaunch to allow subclasses to override
what the default gdb path is.

Change-Id: Icf158633e1c1327cc87ce59c1605bb26258f8708

build/org.eclipse.cdt.build.core/src/org/eclipse/cdt/build/core/CBuildConfiguration.java

@@ -155,8 +155,10 @@ public abstract class CBuildConfiguration extends PlatformObject {
 	}
 
 	public void clearScannerInfoCache() throws CoreException {
+		if (scannerInfoCache != null) {
 			scannerInfoCache.clear();
 		}
+	}
 
 	public Collection<CConsoleParser> getConsoleParsers() throws CoreException {
 		IToolChain toolChain = getToolChain();

dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/gdb/launching/GdbLaunch.java

@@ -437,28 +437,39 @@ public class GdbLaunch extends DsfLaunch implements ITerminate, IDisconnect, ITr
 		super.launchRemoved(launch);
 	}
 
+	/**
+	 * Get the default GDB path if not specified in the launch or launch config.
+	 * 
+	 * @since 5.0
+	 */
+	protected String getDefaultGDBPath() {
+		return Platform.getPreferencesService().getString(GdbPlugin.PLUGIN_ID,
+				IGdbDebugPreferenceConstants.PREF_DEFAULT_GDB_COMMAND,
+				IGDBLaunchConfigurationConstants.DEBUGGER_DEBUG_NAME_DEFAULT, null);
+	}
+
 	/**
 	 * Returns the path to gdb.
 	 * 
 	 * @since 5.0
 	 */
 	public IPath getGDBPath() {
-		String defaultGdbCommand = Platform.getPreferencesService().getString(GdbPlugin.PLUGIN_ID,
-				IGdbDebugPreferenceConstants.PREF_DEFAULT_GDB_COMMAND,
-				IGDBLaunchConfigurationConstants.DEBUGGER_DEBUG_NAME_DEFAULT, null);
-
-		IPath retVal = new Path(defaultGdbCommand);
 		try {
 			String gdb = getAttribute(IGDBLaunchConfigurationConstants.ATTR_DEBUG_NAME);
 			if (gdb == null) {
 				gdb = getLaunchConfiguration().getAttribute(IGDBLaunchConfigurationConstants.ATTR_DEBUG_NAME,
-						defaultGdbCommand);
+						getDefaultGDBPath());
 			}
+			if (gdb != null) {
 				gdb = VariablesPlugin.getDefault().getStringVariableManager().performStringSubstitution(gdb, false);
-			retVal = new Path(gdb);
+				return new Path(gdb);
-		} catch (CoreException e) {
+			} else {
+				return null;
+			}
+		} catch (CoreException e) {
+			GdbPlugin.log(e.getStatus());
+			return null;
 		}
-		return retVal;
 	}
 
 	/**

qt/org.eclipse.cdt.qt.core/plugin.xml

@@ -185,27 +185,22 @@
     <extension
           point="org.eclipse.debug.core.launchConfigurationTypes">
        <launchConfigurationType
+             delegate="org.eclipse.cdt.internal.qt.core.launch.QtLocalRunLaunchConfigDelegate"
              id="org.eclipse.cdt.qt.core.launchConfigurationType"
+             modes="run"
              name="Qt Local Application"
-             public="true">
+             public="true"
+             sourceLocatorId="org.eclipse.cdt.debug.core.sourceLocator"
+             sourcePathComputerId="org.eclipse.cdt.debug.core.sourcePathComputer">
        </launchConfigurationType>
     </extension>
     <extension
           point="org.eclipse.debug.core.launchDelegates">
-       <launchDelegate
-             delegate="org.eclipse.cdt.internal.qt.core.launch.QtLocalRunLaunchConfigDelegate"
-             id="org.eclipse.cdt.qt.core.launchDelegate.run.local"
-             modes="run"
-             name="Qt Local Run launcher"
-             type="org.eclipse.cdt.qt.core.launchConfigurationType">
-       </launchDelegate>
        <launchDelegate
              delegate="org.eclipse.cdt.internal.qt.core.launch.QtLocalDebugLaunchConfigDelegate"
              id="org.eclipse.cdt.qt.core.launchDelegate.debug.local"
              modes="debug"
              name="Qt Local Debug launcher"
-             sourceLocatorId="org.eclipse.cdt.debug.core.sourceLocator"
-             sourcePathComputerId="org.eclipse.cdt.debug.core.sourcePathComputer"
              type="org.eclipse.cdt.qt.core.launchConfigurationType">
        </launchDelegate>
     </extension>

qt/org.eclipse.cdt.qt.core/src/org/eclipse/cdt/internal/qt/core/build/QtBuildConfigurationFactory.java

@@ -27,6 +27,8 @@ import org.eclipse.core.resources.IResourceChangeListener;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IAdapterFactory;
 import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.Status;
 import org.eclipse.launchbar.core.target.ILaunchTarget;
 import org.eclipse.launchbar.core.target.ILaunchTargetManager;
 
@@ -147,7 +149,10 @@ public class QtBuildConfigurationFactory implements IAdapterFactory {
 				}
 			}
 		}
-		return null;
+
+		// No appropriate Qt Install
+		throw new CoreException(
+				new Status(IStatus.ERROR, Activator.ID, "No appropriate Qt SDK found for target " + target.getId()));
 	}
 
 	public static class Cleanup implements IResourceChangeListener {