Fix crash in QTest's signal dumper

It Q_ASSERTs that argv is not a nullptr, so it would fail when an
unconnected signal with 0 arguments was emitted.

Change-Id: I5dd810fbeea5b6b511eff4705efdaa6a55739604
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp
index 1382015d76..63bb386107 100644
--- a/src/corelib/kernel/qobject.cpp
+++ b/src/corelib/kernel/qobject.cpp
@@ -3593,6 +3593,10 @@ void doActivate(QObject *sender, int signal_index, void **argv)
 
     const QSignalSpyCallbackSet *signal_spy_set = callbacks_enabled ? qt_signal_spy_callback_set.load() : nullptr;
 
+    void *empty_argv[] = { nullptr };
+    if (!argv)
+        argv = empty_argv;
+
     if (!sp->isSignalConnected(signal_index, false)) {
         // The possible declarative connection is done, and nothing else is connected
         if (callbacks_enabled && signal_spy_set->signal_begin_callback != nullptr)
@@ -3604,10 +3608,6 @@ void doActivate(QObject *sender, int signal_index, void **argv)
         return;
     }
 
-    void *empty_argv[] = { nullptr };
-    if (!argv)
-        argv = empty_argv;
-
     if (callbacks_enabled && signal_spy_set->signal_begin_callback != nullptr)
         signal_spy_set->signal_begin_callback(sender, signal_index, argv);
     Q_TRACE(QMetaObject_activate_begin_signal, sender, signal_index);