diff --git a/src/tools/moc/generator.cpp b/src/tools/moc/generator.cpp
index f295235c1c..75f1ce00ff 100644
--- a/src/tools/moc/generator.cpp
+++ b/src/tools/moc/generator.cpp
@@ -627,7 +627,7 @@ void Generator::generateCode()
 // Generate internal signal functions
 //
     for (int signalindex = 0; signalindex < int(cdef->signalList.size()); ++signalindex)
-        generateSignal(&cdef->signalList[signalindex], signalindex);
+        generateSignal(&cdef->signalList.at(signalindex), signalindex);
 
 //
 // Generate plugin meta data
@@ -1408,7 +1408,7 @@ void Generator::generateStaticMetacall()
     fprintf(out, "}\n");
 }
 
-void Generator::generateSignal(FunctionDef *def,int index)
+void Generator::generateSignal(const FunctionDef *def, int index)
 {
     if (def->wasCloned || def->isAbstract)
         return;
diff --git a/src/tools/moc/generator.h b/src/tools/moc/generator.h
index 91f8e00d61..2d4d69ca05 100644
--- a/src/tools/moc/generator.h
+++ b/src/tools/moc/generator.h
@@ -40,7 +40,7 @@ private:
     void generateProperties();
     void generateMetacall();
     void generateStaticMetacall();
-    void generateSignal(FunctionDef *def, int index);
+    void generateSignal(const FunctionDef *def, int index);
     void generatePluginMetaData();
     QMultiMap<QByteArray, int> automaticPropertyMetaTypesHelper();
     QMap<int, QMultiMap<QByteArray, int>>