diff --git a/autotests/kconfig_compiler/test8a.h.ref b/autotests/kconfig_compiler/test8a.h.ref
--- a/autotests/kconfig_compiler/test8a.h.ref
+++ b/autotests/kconfig_compiler/test8a.h.ref
@@ -12,7 +12,7 @@
 {
   public:
 
-    Test8a( KSharedConfig::Ptr config = KSharedConfig::openConfig(), QObject *parent = nullptr );
+    Test8a( const KSharedConfig::Ptr &config = KSharedConfig::openConfig(), QObject *parent = nullptr );
     ~Test8a();
 
     /**
diff --git a/autotests/kconfig_compiler/test8a.cpp.ref b/autotests/kconfig_compiler/test8a.cpp.ref
--- a/autotests/kconfig_compiler/test8a.cpp.ref
+++ b/autotests/kconfig_compiler/test8a.cpp.ref
@@ -3,7 +3,7 @@
 
 #include "test8a.h"
 
-Test8a::Test8a( KSharedConfig::Ptr config, QObject *parent )
+Test8a::Test8a( const KSharedConfig::Ptr &config, QObject *parent )
   : KConfigSkeleton( config )
 {
   setParent(parent);
diff --git a/autotests/kconfig_compiler/test8c.h.ref b/autotests/kconfig_compiler/test8c.h.ref
--- a/autotests/kconfig_compiler/test8c.h.ref
+++ b/autotests/kconfig_compiler/test8c.h.ref
@@ -13,7 +13,7 @@
 
     static Test8c *self();
     static void instance(const QString& cfgfilename);
-    static void instance(KSharedConfig::Ptr config);
+    static void instance(const KSharedConfig::Ptr &config);
     ~Test8c();
 
     /**
@@ -55,7 +55,7 @@
     }
 
   protected:
-    Test8c(KSharedConfig::Ptr config, QObject *parent = nullptr);
+    Test8c(const KSharedConfig::Ptr &config, QObject *parent = nullptr);
     friend class Test8cHelper;
 
 
diff --git a/autotests/kconfig_compiler/test8c.cpp.ref b/autotests/kconfig_compiler/test8c.cpp.ref
--- a/autotests/kconfig_compiler/test8c.cpp.ref
+++ b/autotests/kconfig_compiler/test8c.cpp.ref
@@ -35,7 +35,7 @@
   s_globalTest8c()->q->read();
 }
 
-void Test8c::instance(KSharedConfig::Ptr config)
+void Test8c::instance(const KSharedConfig::Ptr & config)
 {
   if (s_globalTest8c()->q) {
      qDebug() << "Test8c::instance called after the first use - ignoring";
@@ -45,7 +45,7 @@
   s_globalTest8c()->q->read();
 }
 
-Test8c::Test8c( KSharedConfig::Ptr config, QObject *parent )
+Test8c::Test8c( const KSharedConfig::Ptr &config, QObject *parent )
   : KConfigSkeleton( config )
 {
   setParent(parent);
diff --git a/src/kconfig_compiler/kconfig_compiler.cpp b/src/kconfig_compiler/kconfig_compiler.cpp
--- a/src/kconfig_compiler/kconfig_compiler.cpp
+++ b/src/kconfig_compiler/kconfig_compiler.cpp
@@ -1887,7 +1887,7 @@
                 h << " const QString &cfgfilename"
                   << (parameters.isEmpty() ? " = QString()" : ", ");
             else
-                h << " KSharedConfig::Ptr config"
+                h << " const KSharedConfig::Ptr &config"
                   << (parameters.isEmpty() ? " = KSharedConfig::openConfig()" : ", ");
         }
         for (QList<Param>::ConstIterator it = parameters.constBegin();
@@ -1908,7 +1908,7 @@
         h << "    static " << cfg.className << " *self();" << endl;
         if (cfgFileNameArg) {
             h << "    static void instance(const QString& cfgfilename);" << endl;
-            h << "    static void instance(KSharedConfig::Ptr config);" << endl;
+            h << "    static void instance(const KSharedConfig::Ptr &config);" << endl;
         }
     }
 
@@ -2131,7 +2131,7 @@
     if (cfg.singleton) {
         h << "    " << cfg.className << "(";
         if (cfgFileNameArg) {
-            h << "KSharedConfig::Ptr config";
+            h << "const KSharedConfig::Ptr &config";
         }
         if (cfg.parentInConstructor) {
             if (cfgFileNameArg) {
@@ -2362,7 +2362,7 @@
                 cpp << "}" << endl << endl;
             };
             instance(QStringLiteral("const QString&"), QStringLiteral("cfgfilename"), true);
-            instance(QStringLiteral("KSharedConfig::Ptr"), QStringLiteral("config"), false);
+            instance(QStringLiteral("const KSharedConfig::Ptr &"), QStringLiteral("config"), false);
         }
     }
 
@@ -2374,7 +2374,7 @@
     cpp << cfg.className << "::" << cfg.className << "(";
     if (cfgFileNameArg) {
         if (! cfg.forceStringFilename) {
-            cpp << " KSharedConfig::Ptr config";
+            cpp << " const KSharedConfig::Ptr &config";
         } else {
             cpp << " const QString& config";
         }