1 files changed, 19 insertions, 30 deletions

diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp
index 0bc0916b39..fc5e6abf00 100644
--- a/src/corelib/kernel/qobject.cpp
+++ b/src/corelib/kernel/qobject.cpp
@@ -3660,33 +3660,17 @@ void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_i
         return;
     }
 
-    // contains the non-empty connection lists
-    const QObjectPrivate::ConnectionList *lists[2];
-    int numLists = 0;
-    if (signal_index < connectionLists->count()) {
-        const auto *list = &connectionLists->at(signal_index);
-        if (list->first) // only add if non-empty
-            lists[numLists++] = list;
-    }
-    if (connectionLists->allsignals.first) // only add if non-empty
-        lists[numLists++] = &connectionLists->allsignals;
+    const QObjectPrivate::ConnectionList *list;
+    if (signal_index < connectionLists->count())
+        list = &connectionLists->at(signal_index);
+    else
+        list = &connectionLists->allsignals;
 
     Qt::HANDLE currentThreadId = QThread::currentThreadId();
 
-    for (int i = 0; i < numLists; ++i) {
-        const auto *list = lists[i];
-        if (i == 0) {
-            // on the first iteration, the mutex must be locked already
-            Q_ASSERT(!locker.mutex()->tryLock());
-        } else {
-            // otherwise the mutex is unlocked and must be relocked
-            locker.relock();
-            if (connectionLists->orphaned)
-                break;
-        }
-
+    do {
         QObjectPrivate::Connection *c = list->first;
-        Q_ASSERT(c);
+        if (!c) continue;
         // We need to check against last here to ensure that signals added
         // during the signal emission are not emitted in this emission.
         QObjectPrivate::Connection *last = list->last;
@@ -3739,6 +3723,8 @@ void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_i
                 // destructor of the slot object might also lock a mutex from the signalSlotLock() mutex pool,
                 // and that would deadlock if the pool happens to return the same mutex.
                 obj.reset();
+
+                locker.relock();
             } else if (c->callFunction && c->method_offset <= receiver->metaObject()->methodOffset()) {
                 //we compare the vtable to make sure we are not in the destructor of the object.
                 const int methodIndex = c->method();
@@ -3752,6 +3738,7 @@ void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_i
 
                 if (qt_signal_spy_callback_set.slot_end_callback != 0)
                     qt_signal_spy_callback_set.slot_end_callback(receiver, methodIndex);
+                locker.relock();
             } else {
                 const int method = c->method_relative + c->method_offset;
                 locker.unlock();
@@ -3766,17 +3753,19 @@ void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_i
 
                 if (qt_signal_spy_callback_set.slot_end_callback != 0)
                     qt_signal_spy_callback_set.slot_end_callback(receiver, method);
-            }
 
-            if (c == last) // early break without relock for the last signal
-                break;
-
-            locker.relock();
+                locker.relock();
+            }
 
             if (connectionLists->orphaned)
                 break;
-        } while ((c = c->nextConnectionList) != 0);
-    }
+        } while (c != last && (c = c->nextConnectionList) != 0);
+
+        if (connectionLists->orphaned)
+            break;
+    } while (list != &connectionLists->allsignals &&
+        //start over for all signals;
+        ((list = &connectionLists->allsignals), true));
 
     }