loplugin:passstuffbyref

Change-Id: Ib2b2650da7abc9260897f9b5aad619a0ea6ae941
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/138052
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

21 files changed, 64 insertions, 58 deletions

diff --git a/compilerplugins/clang/passstuffbyref.cxx b/compilerplugins/clang/passstuffbyref.cxx
index d6ab91fc82a1..549987e43b53 100644
--- a/compilerplugins/clang/passstuffbyref.cxx
+++ b/compilerplugins/clang/passstuffbyref.cxx
@@ -280,7 +280,9 @@ void PassStuffByRef::checkReturnValue(const FunctionDecl * functionDecl, const C
     if (dc.Function("convertItems").Class("ValueParser").Namespace("configmgr").GlobalNamespace()
         || dc.Function("parseListValue").AnonymousNamespace().Namespace("configmgr").GlobalNamespace()
         || dc.Function("parseSingleValue").AnonymousNamespace().Namespace("configmgr").GlobalNamespace()
-        || dc.Function("Create").Class("HandlerComponentBase").Namespace("pcr").GlobalNamespace()) {
+        || dc.Function("Create").Class("HandlerComponentBase").Namespace("pcr").GlobalNamespace()
+        || dc.Function("toAny").Struct("Convert").Namespace("detail").Namespace("comphelper").GlobalNamespace()
+        || dc.Function("makeAny").Namespace("utl").GlobalNamespace()) {
         return;
     }
     if (startswith(type.getAsString(), "struct o3tl::strong_int")) {
@@ -299,6 +301,9 @@ void PassStuffByRef::checkReturnValue(const FunctionDecl * functionDecl, const C
     if (tc.Struct("TranslateId")) {
         return;
     }
+    if (tc.Class("span").Namespace("o3tl")) {
+        return;
+    }
 
     // functionDecl->dump();
 
@@ -332,7 +337,7 @@ bool PassStuffByRef::VisitReturnStmt(const ReturnStmt * returnStmt)
 {
     if (!mbInsideFunctionDecl)
         return true;
-    const Expr* expr = dyn_cast<Expr>(*returnStmt->child_begin())->IgnoreParenCasts();
+    const Expr* expr = dyn_cast<Expr>(*returnStmt->child_begin())->IgnoreParenImpCasts();
 
     if (isReturnExprDisqualified(expr))
         mbFoundReturnValueDisqualifier = true;
@@ -348,6 +353,7 @@ bool PassStuffByRef::isReturnExprDisqualified(const Expr* expr)
     while (true)
     {
         expr = expr->IgnoreParens();
+//        expr->dump();
         if (auto implicitCast = dyn_cast<ImplicitCastExpr>(expr)) {
             expr = implicitCast->getSubExpr();
             continue;
@@ -427,6 +433,9 @@ bool PassStuffByRef::isReturnExprDisqualified(const Expr* expr)
                     return true;
                 // otherwise fall through to the checking below
             }
+            if (Opc == OO_Arrow)
+                if (isReturnExprDisqualified(operatorCallExpr->getArg(0)))
+                    return true;
         }
         if (auto memberCallExpr = dyn_cast<CXXMemberCallExpr>(expr)) {
             if (isReturnExprDisqualified(memberCallExpr->getImplicitObjectArgument()))
@@ -455,21 +464,19 @@ bool PassStuffByRef::isReturnExprDisqualified(const Expr* expr)
 
 bool PassStuffByRef::VisitVarDecl(const VarDecl * varDecl)
 {
-    if (!mbInsideFunctionDecl)
+    if (!mbInsideFunctionDecl || mbFoundReturnValueDisqualifier)
         return true;
     // things guarded by locking are probably best left alone
     loplugin::TypeCheck dc(varDecl->getType());
-    if (dc.Class("Guard").Namespace("osl").GlobalNamespace())
-        mbFoundReturnValueDisqualifier = true;
-    if (dc.Class("ClearableGuard").Namespace("osl").GlobalNamespace())
-        mbFoundReturnValueDisqualifier = true;
-    if (dc.Class("ResettableGuard").Namespace("osl").GlobalNamespace())
-        mbFoundReturnValueDisqualifier = true;
-    else if (dc.Class("SolarMutexGuard").GlobalNamespace())
-        mbFoundReturnValueDisqualifier = true;
-    else if (dc.Class("SfxModelGuard").GlobalNamespace())
-        mbFoundReturnValueDisqualifier = true;
-    else if (dc.Class("ReadWriteGuard").Namespace("utl").GlobalNamespace())
+    if (dc.Class("Guard").Namespace("osl").GlobalNamespace() ||
+        dc.Class("ClearableGuard").Namespace("osl").GlobalNamespace() ||
+        dc.Class("ResettableGuard").Namespace("osl").GlobalNamespace() ||
+        dc.Class("SolarMutexGuard").GlobalNamespace() ||
+        dc.Class("SfxModelGuard").GlobalNamespace() ||
+        dc.Class("ReadWriteGuard").Namespace("utl").GlobalNamespace() ||
+        dc.Class("unique_lock").StdNamespace() ||
+        dc.Class("lock_guard").StdNamespace() ||
+        dc.Class("scoped_lock").StdNamespace())
         mbFoundReturnValueDisqualifier = true;
     return true;
 }
diff --git a/include/svx/ChildrenManager.hxx b/include/svx/ChildrenManager.hxx
index c14ae6c1c476..9f1d071ea9e7 100644
--- a/include/svx/ChildrenManager.hxx
+++ b/include/svx/ChildrenManager.hxx
@@ -137,7 +137,7 @@ public:
     css::uno::Reference<css::accessibility::XAccessible> GetChild(tools::Long nIndex);
     /// @throws css::lang::IndexOutOfBoundsException
     /// @throws css::uno::RuntimeException
-    css::uno::Reference<css::drawing::XShape> GetChildShape(tools::Long nIndex);
+    const css::uno::Reference<css::drawing::XShape>& GetChildShape(tools::Long nIndex);
 
     /** Update the child manager.  Take care of a modified set of children
         and modified visible area.  This method can optimize the update
diff --git a/include/svx/svdobj.hxx b/include/svx/svdobj.hxx
index daf6cde70319..971eba741ec8 100644
--- a/include/svx/svdobj.hxx
+++ b/include/svx/svdobj.hxx
@@ -885,7 +885,7 @@ public:
     void ForceMetricToItemPoolMetric(basegfx::B2DPolyPolygon& rPolyPolygon) const noexcept;
 
 protected:
-    tools::Rectangle getOutRectangle() const;
+    const tools::Rectangle& getOutRectangle() const;
     void setOutRectangleConst(tools::Rectangle const& rRectangle) const; // need to do something about this
     void setOutRectangle(tools::Rectangle const& rRectangle);
     void resetOutRectangle();
diff --git a/oox/source/drawingml/diagram/diagramhelper.cxx b/oox/source/drawingml/diagram/diagramhelper.cxx
index ebd6f3ebbf4a..e0e7202d3966 100644
--- a/oox/source/drawingml/diagram/diagramhelper.cxx
+++ b/oox/source/drawingml/diagram/diagramhelper.cxx
@@ -236,7 +236,7 @@ void AdvancedDiagramHelper::doAnchor(SdrObjGroup& rTarget, ::oox::drawingml::Sha
     anchorToSdrObjGroup(rTarget);
 }
 
-std::shared_ptr< ::oox::drawingml::Theme > AdvancedDiagramHelper::getOrCreateThemePtr(
+const std::shared_ptr< ::oox::drawingml::Theme >& AdvancedDiagramHelper::getOrCreateThemePtr(
     rtl::Reference< oox::shape::ShapeFilterBase >& rxFilter) const
 {
     // (Re-)Use already existing Theme if existing/imported if possible.
diff --git a/oox/source/drawingml/diagram/diagramhelper.hxx b/oox/source/drawingml/diagram/diagramhelper.hxx
index 6059c2261d50..626d40382d7e 100644
--- a/oox/source/drawingml/diagram/diagramhelper.hxx
+++ b/oox/source/drawingml/diagram/diagramhelper.hxx
@@ -83,7 +83,7 @@ public:
     virtual void applyDiagramDataState(const std::shared_ptr< svx::diagram::DiagramDataState >& rState) override;
 
     void doAnchor(SdrObjGroup& rTarget, ::oox::drawingml::Shape& rRootShape);
-    std::shared_ptr< ::oox::drawingml::Theme > getOrCreateThemePtr(
+    const std::shared_ptr< ::oox::drawingml::Theme >& getOrCreateThemePtr(
         rtl::Reference< oox::shape::ShapeFilterBase>& rxFilter ) const;
 };
 
diff --git a/pyuno/source/module/pyuno_adapter.cxx b/pyuno/source/module/pyuno_adapter.cxx
index b15387a2074e..27c7eeae2ec7 100644
--- a/pyuno/source/module/pyuno_adapter.cxx
+++ b/pyuno/source/module/pyuno_adapter.cxx
@@ -65,7 +65,7 @@ Adapter::~Adapter()
     mWrappedObject.scratch();
 }
 
-Sequence<sal_Int8> Adapter::getUnoTunnelId()
+const Sequence<sal_Int8> & Adapter::getUnoTunnelId()
 {
     static const comphelper::UnoIdInit g_id;
     return g_id.getSeq();
diff --git a/pyuno/source/module/pyuno_impl.hxx b/pyuno/source/module/pyuno_impl.hxx
index 9fda901886cb..422f3fdb3dff 100644
--- a/pyuno/source/module/pyuno_impl.hxx
+++ b/pyuno/source/module/pyuno_impl.hxx
@@ -262,7 +262,7 @@ public:
     Adapter( const PyRef &obj,
              const css::uno::Sequence< css::uno::Type > & types );
 
-    static css::uno::Sequence< sal_Int8 > getUnoTunnelId();
+    static const css::uno::Sequence< sal_Int8 > & getUnoTunnelId();
     const PyRef& getWrappedObject() const { return mWrappedObject; }
     const css::uno::Sequence< css::uno::Type >& getWrappedTypes() const { return mTypes; }
     virtual ~Adapter() override;
diff --git a/sfx2/source/dialog/backingwindow.cxx b/sfx2/source/dialog/backingwindow.cxx
index 4a507142bf3b..3506336be76e 100644
--- a/sfx2/source/dialog/backingwindow.cxx
+++ b/sfx2/source/dialog/backingwindow.cxx
@@ -69,7 +69,7 @@ private:
     Size m_BmpSize;
 
 public:
-    Size getSize() { return m_BmpSize; }
+    const Size & getSize() { return m_BmpSize; }
 
     virtual void SetDrawingArea(weld::DrawingArea* pDrawingArea) override
     {
diff --git a/svx/source/accessibility/ChildrenManager.cxx b/svx/source/accessibility/ChildrenManager.cxx
index d0e681b550f1..8b08b930dc7b 100644
--- a/svx/source/accessibility/ChildrenManager.cxx
+++ b/svx/source/accessibility/ChildrenManager.cxx
@@ -59,7 +59,7 @@ css::uno::Reference<XAccessible> ChildrenManager::GetChild (tools::Long nIndex)
     return mpImpl->GetChild (nIndex);
 }
 
-css::uno::Reference<css::drawing::XShape> ChildrenManager::GetChildShape(tools::Long nIndex)
+const css::uno::Reference<css::drawing::XShape>& ChildrenManager::GetChildShape(tools::Long nIndex)
 {
     return mpImpl->GetChildShape(nIndex);
 }
diff --git a/svx/source/accessibility/ChildrenManagerImpl.cxx b/svx/source/accessibility/ChildrenManagerImpl.cxx
index 988bb4532c0c..36fa9ffecdb9 100644
--- a/svx/source/accessibility/ChildrenManagerImpl.cxx
+++ b/svx/source/accessibility/ChildrenManagerImpl.cxx
@@ -114,7 +114,7 @@ tools::Long ChildrenManagerImpl::GetChildCount() const noexcept
 }
 
 
-css::uno::Reference<css::drawing::XShape> ChildrenManagerImpl::GetChildShape(tools::Long nIndex)
+const css::uno::Reference<css::drawing::XShape>& ChildrenManagerImpl::GetChildShape(tools::Long nIndex)
 {
     // Check whether the given index is valid.
     if (nIndex < 0 || o3tl::make_unsigned(nIndex) >= maVisibleChildren.size())
diff --git a/svx/source/accessibility/ChildrenManagerImpl.hxx b/svx/source/accessibility/ChildrenManagerImpl.hxx
index 6b59e22551c3..517530fa64e7 100644
--- a/svx/source/accessibility/ChildrenManagerImpl.hxx
+++ b/svx/source/accessibility/ChildrenManagerImpl.hxx
@@ -119,7 +119,7 @@ public:
 
     /// @throws css::uno::RuntimeException
     /// @throws css::lang::IndexOutOfBoundsException
-    css::uno::Reference<css::drawing::XShape> GetChildShape(tools::Long nIndex);
+    const css::uno::Reference<css::drawing::XShape>& GetChildShape(tools::Long nIndex);
     /** Return the requested accessible child or throw and
         IndexOutOfBoundsException if the given index is invalid.
         @param nIndex
diff --git a/svx/source/svdraw/svdobj.cxx b/svx/source/svdraw/svdobj.cxx
index 585988077edc..995ae52ee9e6 100644
--- a/svx/source/svdraw/svdobj.cxx
+++ b/svx/source/svdraw/svdobj.cxx
@@ -3222,7 +3222,7 @@ void SdrObject::ForceMetricToItemPoolMetric(basegfx::B2DPolyPolygon& rPolyPolygo
     }
 }
 
-tools::Rectangle SdrObject::getOutRectangle() const
+const tools::Rectangle& SdrObject::getOutRectangle() const
 {
     return m_aOutRect;
 }
diff --git a/sw/inc/doc.hxx b/sw/inc/doc.hxx
index 0606ac4c33d1..05afd162cdd1 100644
--- a/sw/inc/doc.hxx
+++ b/sw/inc/doc.hxx
@@ -1624,7 +1624,7 @@ public:
     void SetDefaultPageMode(bool bSquaredPageMode);
     bool IsSquaredPageMode() const;
 
-    css::uno::Reference< ooo::vba::word::XFind > getVbaFind() const { return mxVbaFind; }
+    const css::uno::Reference< ooo::vba::word::XFind >& getVbaFind() const { return mxVbaFind; }
     void setVbaFind( const css::uno::Reference< ooo::vba::word::XFind > &xFind) { mxVbaFind = xFind; }
     css::uno::Reference< css::script::vba::XVBAEventProcessor > const & GetVbaEventProcessor();
     void SetVBATemplateToProjectCache( css::uno::Reference< css::container::XNameContainer > const & xCache ) { m_xTemplateToProjectCache = xCache; };
diff --git a/sw/inc/formatcontentcontrol.hxx b/sw/inc/formatcontentcontrol.hxx
index d7fc62fc2ecd..d265d2f098e9 100644
--- a/sw/inc/formatcontentcontrol.hxx
+++ b/sw/inc/formatcontentcontrol.hxx
@@ -78,7 +78,6 @@ public:
      */
     void NotifyChangeTextNode(SwTextNode* pTextNode);
     static SwFormatContentControl* CreatePoolDefault(sal_uInt16 nWhich);
-    std::shared_ptr<SwContentControl> GetContentControl() { return m_pContentControl; }
     const std::shared_ptr<SwContentControl>& GetContentControl() const { return m_pContentControl; }
 
     void dumpAsXml(xmlTextWriterPtr pWriter) const override;
@@ -95,7 +94,7 @@ public:
 
     void dumpAsXml(xmlTextWriterPtr pWriter) const;
 
-    OUString ToString() const;
+    const OUString& ToString() const;
 
     bool operator==(const SwContentControlListItem& rOther) const;
 
@@ -216,13 +215,13 @@ public:
 
     void SetCheckedState(const OUString& rCheckedState) { m_aCheckedState = rCheckedState; }
 
-    OUString GetCheckedState() const { return m_aCheckedState; }
+    const OUString& GetCheckedState() const { return m_aCheckedState; }
 
     void SetUncheckedState(const OUString& rUncheckedState) { m_aUncheckedState = rUncheckedState; }
 
-    OUString GetUncheckedState() const { return m_aUncheckedState; }
+    const OUString& GetUncheckedState() const { return m_aUncheckedState; }
 
-    std::vector<SwContentControlListItem> GetListItems() const { return m_aListItems; }
+    const std::vector<SwContentControlListItem>& GetListItems() const { return m_aListItems; }
 
     bool HasListItems() const { return !m_aListItems.empty(); }
 
@@ -241,15 +240,15 @@ public:
 
     void SetDateFormat(const OUString& rDateFormat) { m_aDateFormat = rDateFormat; }
 
-    OUString GetDateFormat() const { return m_aDateFormat; }
+    const OUString& GetDateFormat() const { return m_aDateFormat; }
 
     void SetDateLanguage(const OUString& rDateLanguage) { m_aDateLanguage = rDateLanguage; }
 
-    OUString GetDateLanguage() const { return m_aDateLanguage; }
+    const OUString& GetDateLanguage() const { return m_aDateLanguage; }
 
     void SetCurrentDate(const OUString& rCurrentDate) { m_aCurrentDate = rCurrentDate; }
 
-    OUString GetCurrentDate() const { return m_aCurrentDate; }
+    const OUString& GetCurrentDate() const { return m_aCurrentDate; }
 
     /// Formats fCurrentDate and sets it.
     void SetCurrentDateValue(double fCurrentDate);
@@ -269,18 +268,18 @@ public:
         m_aPlaceholderDocPart = rPlaceholderDocPart;
     }
 
-    OUString GetPlaceholderDocPart() const { return m_aPlaceholderDocPart; }
+    const OUString& GetPlaceholderDocPart() const { return m_aPlaceholderDocPart; }
 
     void SetSelectedListItem(std::optional<size_t> oSelectedListItem)
     {
         m_oSelectedListItem = oSelectedListItem;
     }
 
-    std::optional<size_t> GetSelectedListItem() const { return m_oSelectedListItem; }
+    const std::optional<size_t>& GetSelectedListItem() const { return m_oSelectedListItem; }
 
     void SetSelectedDate(std::optional<double> oSelectedDate) { m_oSelectedDate = oSelectedDate; }
 
-    std::optional<double> GetSelectedDate() const { return m_oSelectedDate; }
+    const std::optional<double>& GetSelectedDate() const { return m_oSelectedDate; }
 
     /// Should this character (during key input) interact with the content control?
     bool IsInteractingCharacter(sal_Unicode cCh);
@@ -295,25 +294,25 @@ public:
         m_aDataBindingPrefixMappings = rDataBindingPrefixMappings;
     }
 
-    OUString GetDataBindingPrefixMappings() const { return m_aDataBindingPrefixMappings; }
+    const OUString& GetDataBindingPrefixMappings() const { return m_aDataBindingPrefixMappings; }
 
     void SetDataBindingXpath(const OUString& rDataBindingXpath)
     {
         m_aDataBindingXpath = rDataBindingXpath;
     }
 
-    OUString GetDataBindingXpath() const { return m_aDataBindingXpath; }
+    const OUString& GetDataBindingXpath() const { return m_aDataBindingXpath; }
 
     void SetDataBindingStoreItemID(const OUString& rDataBindingStoreItemID)
     {
         m_aDataBindingStoreItemID = rDataBindingStoreItemID;
     }
 
-    OUString GetDataBindingStoreItemID() const { return m_aDataBindingStoreItemID; }
+    const OUString& GetDataBindingStoreItemID() const { return m_aDataBindingStoreItemID; }
 
     void SetColor(const OUString& rColor) { m_aColor = rColor; }
 
-    OUString GetColor() const { return m_aColor; }
+    const OUString& GetColor() const { return m_aColor; }
 
     void SetReadWrite(bool bReadWrite) { m_bReadWrite = bReadWrite; }
 
diff --git a/sw/inc/viscrs.hxx b/sw/inc/viscrs.hxx
index 6126f5ffa0c0..6c41fcb61b7e 100644
--- a/sw/inc/viscrs.hxx
+++ b/sw/inc/viscrs.hxx
@@ -115,7 +115,7 @@ public:
 
     void SetShowContentControlOverlay(const bool bShow) { m_bShowContentControlOverlay = bShow; }
 
-    VclPtr<SwContentControlButton> GetContentControlButton() const;
+    const VclPtr<SwContentControlButton>& GetContentControlButton() const;
 
     const SwCursorShell* GetShell() const { return m_pCursorShell; }
     // check current MapMode of the shell and set possibly the static members.
diff --git a/sw/source/core/crsr/viscrs.cxx b/sw/source/core/crsr/viscrs.cxx
index 8246dfcf8dd8..588f572de73d 100644
--- a/sw/source/core/crsr/viscrs.cxx
+++ b/sw/source/core/crsr/viscrs.cxx
@@ -796,7 +796,7 @@ void SwSelPaintRects::HighlightContentControl()
     }
 }
 
-VclPtr<SwContentControlButton> SwSelPaintRects::GetContentControlButton() const
+const VclPtr<SwContentControlButton>& SwSelPaintRects::GetContentControlButton() const
 {
     return m_pContentControlButton;
 }
diff --git a/sw/source/core/txtnode/attrcontentcontrol.cxx b/sw/source/core/txtnode/attrcontentcontrol.cxx
index f809b1b26cc5..b9992975f05a 100644
--- a/sw/source/core/txtnode/attrcontentcontrol.cxx
+++ b/sw/source/core/txtnode/attrcontentcontrol.cxx
@@ -395,7 +395,7 @@ void SwContentControlListItem::dumpAsXml(xmlTextWriterPtr pWriter) const
     (void)xmlTextWriterEndElement(pWriter);
 }
 
-OUString SwContentControlListItem::ToString() const
+const OUString& SwContentControlListItem::ToString() const
 {
     if (!m_aDisplayText.isEmpty())
     {
diff --git a/ucbhelper/source/client/content.cxx b/ucbhelper/source/client/content.cxx
index 48d3ee84a9da..8feab846baee 100644
--- a/ucbhelper/source/client/content.cxx
+++ b/ucbhelper/source/client/content.cxx
@@ -164,7 +164,7 @@ friend ContentEventListener_Impl;
 private:
     void reinit( const Reference< XContent >& xContent );
     void disposing(const EventObject& Source);
-    Reference< XContent > getContent_NoLock();
+    const Reference< XContent > & getContent_NoLock();
     const OUString& getURL_NoLock() const;
 
 public:
@@ -1205,7 +1205,7 @@ Reference< XContent > Content_Impl::getContent()
     return m_xContent;
 }
 
-Reference< XContent > Content_Impl::getContent_NoLock()
+const Reference< XContent > & Content_Impl::getContent_NoLock()
 {
     if ( !m_xContent.is() && !m_aURL.isEmpty() )
     {
diff --git a/vcl/source/treelist/treelistbox.cxx b/vcl/source/treelist/treelistbox.cxx
index e5062c085b80..e799de53ff31 100644
--- a/vcl/source/treelist/treelistbox.cxx
+++ b/vcl/source/treelist/treelistbox.cxx
@@ -84,7 +84,7 @@ public:
     OUString const & GetSavedValue() const;
     void        StopEditing( bool bCancel );
     void        Hide();
-    VclPtr<Edit> GetEditWidget() const { return pEdit; };
+    const VclPtr<Edit> & GetEditWidget() const { return pEdit; };
 };
 
 // ***************************************************************
diff --git a/writerfilter/source/dmapper/SdtHelper.cxx b/writerfilter/source/dmapper/SdtHelper.cxx
index 1df5319f85f3..32570db71813 100644
--- a/writerfilter/source/dmapper/SdtHelper.cxx
+++ b/writerfilter/source/dmapper/SdtHelper.cxx
@@ -430,14 +430,14 @@ bool SdtHelper::GetChecked() const { return m_bChecked; }
 
 void SdtHelper::SetCheckedState(const OUString& rCheckedState) { m_aCheckedState = rCheckedState; }
 
-OUString SdtHelper::GetCheckedState() const { return m_aCheckedState; }
+const OUString& SdtHelper::GetCheckedState() const { return m_aCheckedState; }
 
 void SdtHelper::SetUncheckedState(const OUString& rUncheckedState)
 {
     m_aUncheckedState = rUncheckedState;
 }
 
-OUString SdtHelper::GetUncheckedState() const { return m_aUncheckedState; }
+const OUString& SdtHelper::GetUncheckedState() const { return m_aUncheckedState; }
 
 void SdtHelper::clear()
 {
@@ -460,11 +460,11 @@ void SdtHelper::SetPlaceholderDocPart(const OUString& rPlaceholderDocPart)
     m_aPlaceholderDocPart = rPlaceholderDocPart;
 }
 
-OUString SdtHelper::GetPlaceholderDocPart() const { return m_aPlaceholderDocPart; }
+const OUString& SdtHelper::GetPlaceholderDocPart() const { return m_aPlaceholderDocPart; }
 
 void SdtHelper::SetColor(const OUString& rColor) { m_aColor = rColor; }
 
-OUString SdtHelper::GetColor() const { return m_aColor; }
+const OUString& SdtHelper::GetColor() const { return m_aColor; }
 
 } // namespace writerfilter::dmapper
 
diff --git a/writerfilter/source/dmapper/SdtHelper.hxx b/writerfilter/source/dmapper/SdtHelper.hxx
index fbf33de2c0fc..7be862cd45f4 100644
--- a/writerfilter/source/dmapper/SdtHelper.hxx
+++ b/writerfilter/source/dmapper/SdtHelper.hxx
@@ -143,13 +143,13 @@ public:
     {
         m_sDataBindingPrefixMapping = sValue;
     }
-    OUString GetDataBindingPrefixMapping() const { return m_sDataBindingPrefixMapping; }
+    const OUString& GetDataBindingPrefixMapping() const { return m_sDataBindingPrefixMapping; }
 
     void setDataBindingXPath(const OUString& sValue) { m_sDataBindingXPath = sValue; }
-    OUString GetDataBindingXPath() const { return m_sDataBindingXPath; }
+    const OUString& GetDataBindingXPath() const { return m_sDataBindingXPath; }
 
     void setDataBindingStoreItemID(const OUString& sValue) { m_sDataBindingStoreItemID = sValue; }
-    OUString GetDataBindingStoreItemID() const { return m_sDataBindingStoreItemID; }
+    const OUString& GetDataBindingStoreItemID() const { return m_sDataBindingStoreItemID; }
 
     void setDateFieldStartRange(const css::uno::Reference<css::text::XTextRange>& xStartRange)
     {
@@ -192,18 +192,18 @@ public:
     void SetChecked();
     bool GetChecked() const;
     void SetCheckedState(const OUString& rCheckedState);
-    OUString GetCheckedState() const;
+    const OUString& GetCheckedState() const;
     void SetUncheckedState(const OUString& rUncheckedState);
-    OUString GetUncheckedState() const;
+    const OUString& GetUncheckedState() const;
 
     /// Clear all collected attributes for further reuse
     void clear();
 
     void SetPlaceholderDocPart(const OUString& rPlaceholderDocPart);
-    OUString GetPlaceholderDocPart() const;
+    const OUString& GetPlaceholderDocPart() const;
 
     void SetColor(const OUString& rColor);
-    OUString GetColor() const;
+    const OUString& GetColor() const;
 };
 
 } // namespace writerfilter::dmapper