Fix 'Attach Debugger' in output pane.

Bring back the slot, suppress a warning about empty binaries
in the release check.

Task-number: QTCREATORBUG-7677
Change-Id: I2f1703b38b68995a1e2533ed8a6c94985cc3b430
Reviewed-by: hjk <qthjk@ovi.com>

src/plugins/debugger/debuggercore.h

@@ -52,6 +52,10 @@ namespace Utils {
 class SavedAction;
 }
 
+namespace ProjectExplorer {
+class RunControl;
+}
+
 namespace Debugger {
 
 class DebuggerEngine;
@@ -122,6 +126,9 @@ public:
 
     virtual DebuggerToolTipManager *toolTipManager() const = 0;
     virtual QSharedPointer<GlobalDebuggerOptions> globalDebuggerOptions() const = 0;
+
+public slots:
+    virtual void attachExternalApplication(ProjectExplorer::RunControl *rc) = 0;
 };
 
 // This is the only way to access the global object.

src/plugins/debugger/debuggerplugin.cpp

@@ -888,6 +888,7 @@ public slots:
     void attachToRemoteServer();
     void attachToProcess(bool startServerOnly);
     void attachToRunningApplication();
+    void attachExternalApplication(ProjectExplorer::RunControl *rc);
     void attachToQmlPort();
     void startRemoteEngine();
     void runScheduled();
@@ -1684,6 +1685,18 @@ void DebuggerPluginPrivate::attachToProcess(bool startServerOnly)
     }
 }
 
+void DebuggerPluginPrivate::attachExternalApplication(ProjectExplorer::RunControl *rc)
+{
+    DebuggerStartParameters sp;
+    fillParameters(&sp);
+    sp.attachPID = rc->applicationProcessHandle().pid();
+    sp.displayName = tr("Process %1").arg(sp.attachPID);
+    sp.startMode = AttachExternal;
+    sp.closeMode = DetachAtClose;
+    sp.toolChainAbi = rc->abi();
+    DebuggerRunControlFactory::createAndScheduleRun(sp);
+}
+
 void DebuggerPluginPrivate::attachToQmlPort()
 {
     DebuggerStartParameters sp;

src/plugins/debugger/gdb/gdbengine.cpp

@@ -5235,7 +5235,9 @@ bool GdbEngine::attemptQuickStart() const
 
 void GdbEngine::checkForReleaseBuild()
 {
-    QString binary = startParameters().executable;
+    const QString binary = startParameters().executable;
+    if (binary.isEmpty())
+        return;
     ElfReader reader(binary);
     ElfData elfData = reader.readHeaders();
     QString error = reader.errorString();