Fix crash when using signaldumper and sender is deleted

Testlib's signaldumper functionality would crash inside
testlib as it dereferenced the sender after it was deleted.

Change-Id: I6013b75b0a121e2768429d8a3cf0339a940314f2
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/corelib/kernel/qobject.cpp

@@ -3908,11 +3908,12 @@ void doActivate(QObject *sender, int signal_index, void **argv)
         if (connections->currentConnectionId.loadRelaxed() == 0)
             senderDeleted = true;
     }
-    if (!senderDeleted)
+    if (!senderDeleted) {
         sp->connections.loadRelaxed()->cleanOrphanedConnections(sender);
 
-    if (callbacks_enabled && signal_spy_set->signal_end_callback != nullptr)
+        if (callbacks_enabled && signal_spy_set->signal_end_callback != nullptr)
-        signal_spy_set->signal_end_callback(sender, signal_index);
+            signal_spy_set->signal_end_callback(sender, signal_index);
+    }
 }
 
 /*!

tests/auto/testlib/selftests/expected_signaldumper.lightxml

@@ -568,11 +568,18 @@
 <Incident type="pass" file="" line="0" />
     <Duration msecs="0"/>
 </TestFunction>
+<TestFunction name="deletingSender">
+<Message type="info" file="" line="0">
+    <Description><![CDATA[Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()]]></Description>
+</Message>
+<Incident type="pass" file="" line="0" />
+    <Duration msecs="0"/>
+</TestFunction>
 <TestFunction name="cleanupTestCase">
 <Incident type="pass" file="" line="0" />
     <Duration msecs="0"/>
 </TestFunction>
 <Message type="info" file="" line="0">
-    <Description><![CDATA[Signal: QThread(_POINTER_) finished ()]]></Description>
+    <Description><![CDATA[    Signal: QThread(_POINTER_) finished ()]]></Description>
 </Message>
 <Duration msecs="0"/>

tests/auto/testlib/selftests/expected_signaldumper.tap

@@ -143,9 +143,11 @@ ok 18 - slotEmittingSignalOldSyntax(queued)
 # Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())
 # Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())
 ok 19 - variousTypes()
-ok 20 - cleanupTestCase()
+# Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()
-# Signal: QThread(_POINTER_) finished ()
+ok 20 - deletingSender()
-1..20
+ok 21 - cleanupTestCase()
-# tests 20
+#     Signal: QThread(_POINTER_) finished ()
-# pass 20
+1..21
+# tests 21
+# pass 21
 # fail 0

tests/auto/testlib/selftests/expected_signaldumper.teamcity

@@ -56,6 +56,9 @@
 ##teamcity[testStarted name='variousTypes()' flowId='tst_Signaldumper']
 ##teamcity[testStdOut name='variousTypes()' out='INFO: Signal: SignalSlotClass(_POINTER_) qStringSignal (QString(Test string))|nINFO: Signal: SignalSlotClass(_POINTER_) qStringRefSignal ((QString&)@_POINTER_)|nINFO: Signal: SignalSlotClass(_POINTER_) qStringConstRefSignal (QString(Test string))|nINFO: Signal: SignalSlotClass(_POINTER_) qByteArraySignal (QByteArray(Test bytearray))|nINFO: Signal: SignalSlotClass(_POINTER_) qListSignal (QList<int>())|nINFO: Signal: SignalSlotClass(_POINTER_) qVectorSignal (QVector<int>())|nINFO: Signal: SignalSlotClass(_POINTER_) qVectorRefSignal ((QVector<int>&)@_POINTER_)|nINFO: Signal: SignalSlotClass(_POINTER_) qVectorConstRefSignal (QVector<int>())|nINFO: Signal: SignalSlotClass(_POINTER_) qVectorConstPointerSignal ((const QVector<int>*)_POINTER_)|nINFO: Signal: SignalSlotClass(_POINTER_) qVectorPointerConstSignal ()|nINFO: Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())|nINFO: Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())' flowId='tst_Signaldumper']
 ##teamcity[testFinished name='variousTypes()' flowId='tst_Signaldumper']
+##teamcity[testStarted name='deletingSender()' flowId='tst_Signaldumper']
+##teamcity[testStdOut name='deletingSender()' out='INFO: Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()' flowId='tst_Signaldumper']
+##teamcity[testFinished name='deletingSender()' flowId='tst_Signaldumper']
 ##teamcity[testStarted name='cleanupTestCase()' flowId='tst_Signaldumper']
 ##teamcity[testFinished name='cleanupTestCase()' flowId='tst_Signaldumper']
 ##teamcity[testSuiteFinished name='tst_Signaldumper' flowId='tst_Signaldumper']

tests/auto/testlib/selftests/expected_signaldumper.txt

@@ -143,7 +143,9 @@ INFO   : tst_Signaldumper::variousTypes() Signal: SignalSlotClass(_POINTER_) qVe
 INFO   : tst_Signaldumper::variousTypes() Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())
 INFO   : tst_Signaldumper::variousTypes() Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())
 PASS   : tst_Signaldumper::variousTypes()
+INFO   : tst_Signaldumper::deletingSender() Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()
+PASS   : tst_Signaldumper::deletingSender()
 PASS   : tst_Signaldumper::cleanupTestCase()
-INFO   : tst_Signaldumper::UnknownTestFunc() Signal: QThread(_POINTER_) finished ()
+INFO   : tst_Signaldumper::UnknownTestFunc()     Signal: QThread(_POINTER_) finished ()
-Totals: 20 passed, 0 failed, 0 skipped, 0 blacklisted, 0ms
+Totals: 21 passed, 0 failed, 0 skipped, 0 blacklisted, 0ms
 ********* Finished testing of tst_Signaldumper *********

tests/auto/testlib/selftests/expected_signaldumper.xml

@@ -570,12 +570,19 @@
 <Incident type="pass" file="" line="0" />
     <Duration msecs="0"/>
 </TestFunction>
+<TestFunction name="deletingSender">
+<Message type="info" file="" line="0">
+    <Description><![CDATA[Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()]]></Description>
+</Message>
+<Incident type="pass" file="" line="0" />
+    <Duration msecs="0"/>
+</TestFunction>
 <TestFunction name="cleanupTestCase">
 <Incident type="pass" file="" line="0" />
     <Duration msecs="0"/>
 </TestFunction>
 <Message type="info" file="" line="0">
-    <Description><![CDATA[Signal: QThread(_POINTER_) finished ()]]></Description>
+    <Description><![CDATA[    Signal: QThread(_POINTER_) finished ()]]></Description>
 </Message>
 <Duration msecs="0"/>
 </TestCase>

tests/auto/testlib/selftests/expected_signaldumper.xunitxml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8" ?>
-<testsuite errors="125" failures="0" tests="12" name="tst_Signaldumper">
+<testsuite errors="126" failures="0" tests="13" name="tst_Signaldumper">
   <properties>
     <property value="@INSERT_QT_VERSION_HERE@" name="QTestVersion"/>
     <property value="@INSERT_QT_VERSION_HERE@" name="QtVersion"/>
@@ -151,8 +151,11 @@
     <!-- message="Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())" type="info" -->
     <!-- message="Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())" type="info" -->
   </testcase>
+  <testcase result="pass" name="deletingSender">
+    <!-- message="Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()" type="info" -->
+  </testcase>
   <testcase result="pass" name="cleanupTestCase">
-    <!-- message="Signal: QThread(_POINTER_) finished ()" type="info" -->
+    <!-- message="    Signal: QThread(_POINTER_) finished ()" type="info" -->
   </testcase>
   <system-err>
 <![CDATA[Signal: QThread(_POINTER_) started ()]]>
@@ -279,6 +282,7 @@
 <![CDATA[Signal: SignalSlotClass(_POINTER_) qVectorPointerConstSignal ()]]>
 <![CDATA[Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())]]>
 <![CDATA[Signal: SignalSlotClass(_POINTER_) qVariantSignal (QVariant())]]>
-<![CDATA[Signal: QThread(_POINTER_) finished ()]]>
+<![CDATA[Signal: SignalSlotClass(_POINTER_) signalWithoutParameters ()]]>
+<![CDATA[    Signal: QThread(_POINTER_) finished ()]]>
   </system-err>
 </testsuite>

tests/auto/testlib/selftests/signaldumper/tst_signaldumper.cpp

@@ -56,6 +56,8 @@ private slots:
     void slotEmittingSignalOldSyntax();
 
     void variousTypes();
+
+    void deletingSender();
 };
 
 void tst_Signaldumper::addConnectionTypeData()
@@ -413,5 +415,14 @@ void tst_Signaldumper::variousTypes()
     emit signalSlotOwner.qVariantSignal(variant);
 }
 
+void tst_Signaldumper::deletingSender()
+{
+    SignalSlotClass *signalSlotOwner = new SignalSlotClass();
+    connect(signalSlotOwner, &SignalSlotClass::signalWithoutParameters, [signalSlotOwner]() {
+        delete signalSlotOwner;
+    });
+    emit signalSlotOwner->signalWithoutParameters();
+}
+
 QTEST_MAIN(tst_Signaldumper)
 #include "tst_signaldumper.moc"