loplugin:staticconstfield improvements

Change-Id: Ia0a19736dfd4500bb17b04c072710f8ee8744031
Reviewed-on: https://gerrit.libreoffice.org/60526
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

25 files changed, 184 insertions, 107 deletions

diff --git a/compilerplugins/clang/staticconstfield.cxx b/compilerplugins/clang/staticconstfield.cxx
index 7276d7e05c49..bfc32a8c059f 100644
--- a/compilerplugins/clang/staticconstfield.cxx
+++ b/compilerplugins/clang/staticconstfield.cxx
@@ -33,22 +33,66 @@ bool StaticConstField::TraverseConstructorInitializer(CXXCtorInitializer* init)
         return true;
     if (!init->getMember())
         return true;
-    auto tc = loplugin::TypeCheck(init->getMember()->getType());
-    if (!tc.Const().Class("OUString").Namespace("rtl").GlobalNamespace()
-        && !tc.Const().Class("OString").Namespace("rtl").GlobalNamespace())
+    auto type = init->getMember()->getType();
+    auto tc = loplugin::TypeCheck(type);
+    bool found = false;
+    if (!tc.Const())
         return true;
-    if (auto constructExpr = dyn_cast<CXXConstructExpr>(init->getInit()))
+    if (tc.Const().Class("OUString").Namespace("rtl").GlobalNamespace()
+        || tc.Const().Class("OString").Namespace("rtl").GlobalNamespace())
     {
-        if (constructExpr->getNumArgs() >= 1 && isa<clang::StringLiteral>(constructExpr->getArg(0)))
+        if (auto constructExpr = dyn_cast<CXXConstructExpr>(init->getInit()))
         {
-            report(DiagnosticsEngine::Warning, "string field can be static const",
-                   init->getSourceLocation())
-                << init->getSourceRange();
-            report(DiagnosticsEngine::Note, "field here", init->getMember()->getLocation())
-                << init->getMember()->getSourceRange();
+            if (constructExpr->getNumArgs() >= 1
+                && isa<clang::StringLiteral>(constructExpr->getArg(0)))
+                found = true;
         }
     }
-    return RecursiveASTVisitor::TraverseConstructorInitializer(init);
+    else if (type->isIntegerType())
+    {
+        if (isa<IntegerLiteral>(init->getInit()->IgnoreParenImpCasts()))
+            found = true;
+        // isIntegerType includes bool
+        else if (isa<CXXBoolLiteralExpr>(init->getInit()->IgnoreParenImpCasts()))
+            found = true;
+    }
+    else if (type->isFloatingType())
+    {
+        if (isa<FloatingLiteral>(init->getInit()->IgnoreParenImpCasts()))
+            found = true;
+    }
+    else if (type->isEnumeralType())
+    {
+        if (auto declRefExpr = dyn_cast<DeclRefExpr>(init->getInit()->IgnoreParenImpCasts()))
+        {
+            if (isa<EnumConstantDecl>(declRefExpr->getDecl()))
+                found = true;
+        }
+    }
+
+    // If we find more than one non-copy-move constructor, we can't say for sure if a member can be static
+    // because it could be initialised differently in each constructor.
+    if (auto cxxRecordDecl = dyn_cast<CXXRecordDecl>(init->getMember()->getParent()))
+    {
+        int cnt = 0;
+        for (auto it = cxxRecordDecl->ctor_begin(); it != cxxRecordDecl->ctor_end(); ++it)
+        {
+            if (!it->isCopyOrMoveConstructor())
+                cnt++;
+        }
+        if (cnt > 1)
+            return true;
+    }
+
+    if (found)
+    {
+        report(DiagnosticsEngine::Warning, "field can be static const", init->getSourceLocation())
+            << init->getSourceRange();
+        report(DiagnosticsEngine::Note, "field here", init->getMember()->getLocation())
+            << init->getMember()->getSourceRange();
+    }
+
+    return true;
 }
 
 loplugin::Plugin::Registration<StaticConstField> X("staticconstfield", true);
diff --git a/compilerplugins/clang/test/staticconstfield.cxx b/compilerplugins/clang/test/staticconstfield.cxx
index 49b326f7d76e..03708fcaa9fd 100644
--- a/compilerplugins/clang/test/staticconstfield.cxx
+++ b/compilerplugins/clang/test/staticconstfield.cxx
@@ -15,7 +15,7 @@ class Class1
     OUString const m_field1; // expected-note {{field here [loplugin:staticconstfield]}}
     Class1()
         : m_field1("xxxx")
-    // expected-error@-1 {{string field can be static const [loplugin:staticconstfield]}}
+    // expected-error@-1 {{field can be static const [loplugin:staticconstfield]}}
     {
         (void)m_field1;
     }
@@ -26,7 +26,7 @@ class Class2
     OString const m_field1; // expected-note {{field here [loplugin:staticconstfield]}}
     Class2()
         : m_field1("xxxx")
-    // expected-error@-1 {{string field can be static const [loplugin:staticconstfield]}}
+    // expected-error@-1 {{field can be static const [loplugin:staticconstfield]}}
     {
         (void)m_field1;
     }
@@ -43,4 +43,71 @@ class Class4
     }
 };
 
+class Class5
+{
+    enum class Enum
+    {
+        ONE
+    };
+    float const m_field1; // expected-note {{field here [loplugin:staticconstfield]}}
+    int const m_field2; // expected-note {{field here [loplugin:staticconstfield]}}
+    bool const m_field3; // expected-note {{field here [loplugin:staticconstfield]}}
+    Enum const m_field4; // expected-note {{field here [loplugin:staticconstfield]}}
+    Class5()
+        : m_field1(1.0)
+        // expected-error@-1 {{field can be static const [loplugin:staticconstfield]}}
+        , m_field2(1)
+        // expected-error@-1 {{field can be static const [loplugin:staticconstfield]}}
+        , m_field3(true)
+        // expected-error@-1 {{field can be static const [loplugin:staticconstfield]}}
+        , m_field4(Enum::ONE)
+    // expected-error@-1 {{field can be static const [loplugin:staticconstfield]}}
+    {
+        (void)m_field1;
+        (void)m_field2;
+        (void)m_field3;
+        (void)m_field4;
+    }
+};
+
+// no warning expected
+class Class6
+{
+    enum class Enum
+    {
+        ONE
+    };
+    float m_field1;
+    int m_field2;
+    bool m_field3;
+    Enum m_field4;
+    Class6()
+        : m_field1(1.0)
+        , m_field2(1)
+        , m_field3(true)
+        , m_field4(Enum::ONE)
+    {
+        (void)m_field1;
+        (void)m_field2;
+        (void)m_field3;
+        (void)m_field4;
+    }
+};
+
+// no warning expected, checking for assigning to const field from multiple constructors
+class Class7
+{
+    bool const m_field1;
+    Class7()
+        : m_field1(true)
+    {
+        (void)m_field1;
+    }
+    Class7(bool b)
+        : m_field1(b)
+    {
+        (void)m_field1;
+    }
+};
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/cppcanvas/source/mtfrenderer/transparencygroupaction.cxx b/cppcanvas/source/mtfrenderer/transparencygroupaction.cxx
index c7cd718fc805..8fdfca98a39e 100644
--- a/cppcanvas/source/mtfrenderer/transparencygroupaction.cxx
+++ b/cppcanvas/source/mtfrenderer/transparencygroupaction.cxx
@@ -120,7 +120,6 @@ namespace cppcanvas
                 // mxBufferBitmap content
                 CanvasSharedPtr                                     mpCanvas;
                 rendering::RenderState                              maState;
-                const double                                        mnAlpha;
             };
 
 
@@ -151,8 +150,7 @@ namespace cppcanvas
                 mxBufferBitmap(),
                 maLastTransformation(),
                 mpCanvas( rCanvas ),
-                maState(),
-                mnAlpha( 1.0 )
+                maState()
             {
                 tools::initRenderState(maState,rState);
                 implSetupTransform( maState, rDstPoint );
@@ -400,27 +398,10 @@ namespace cppcanvas
                 aLocalState.DeviceColor = maState.DeviceColor;
 #endif
 
-                if( ::rtl::math::approxEqual(mnAlpha, 1.0) )
-                {
-                    // no further alpha changes necessary -> draw directly
-                    mpCanvas->getUNOCanvas()->drawBitmap( mxBufferBitmap,
-                                                          mpCanvas->getViewState(),
-                                                          aLocalState );
-                }
-                else
-                {
-                    // add alpha modulation value to DeviceColor
-                    uno::Sequence<rendering::ARGBColor> aCols(1);
-                    aCols[0] = rendering::ARGBColor( mnAlpha, 1.0, 1.0, 1.0);
-                    aLocalState.DeviceColor =
-                        mpCanvas->getUNOCanvas()->getDevice()->getDeviceColorSpace()->convertFromARGB(
-                            aCols);
-
-                    mpCanvas->getUNOCanvas()->drawBitmapModulated( mxBufferBitmap,
-                                                                   mpCanvas->getViewState(),
-                                                                   aLocalState );
-                }
-
+                // no further alpha changes necessary -> draw directly
+                mpCanvas->getUNOCanvas()->drawBitmap( mxBufferBitmap,
+                                                      mpCanvas->getViewState(),
+                                                      aLocalState );
                 return true;
             }
 
diff --git a/desktop/source/splash/splash.cxx b/desktop/source/splash/splash.cxx
index b7724ec1e636..336601a6d80f 100644
--- a/desktop/source/splash/splash.cxx
+++ b/desktop/source/splash/splash.cxx
@@ -99,7 +99,7 @@ private:
     long        _barheight, _barspace, _textBaseline;
     double      _fXPos, _fYPos;
     double      _fWidth, _fHeight;
-    const long  _xoffset, _yoffset;
+    static constexpr long  _xoffset = 12, _yoffset = 18;
 
 public:
     SplashScreen();
@@ -172,8 +172,6 @@ SplashScreen::SplashScreen()
     , _fYPos(-1.0)
     , _fWidth(-1.0)
     , _fHeight(-1.0)
-    , _xoffset(12)
-    , _yoffset(18)
 {
     loadConfig();
 }
diff --git a/include/vcl/opengl/OpenGLContext.hxx b/include/vcl/opengl/OpenGLContext.hxx
index a5493c0d6927..1253a4f02091 100644
--- a/include/vcl/opengl/OpenGLContext.hxx
+++ b/include/vcl/opengl/OpenGLContext.hxx
@@ -168,7 +168,6 @@ protected:
     bool mbInitialized;
     int  mnRefCount;
     bool mbRequestLegacyContext;
-    bool const mbUseDoubleBufferedRendering;
     bool mbVCLOnly;
 
     int mnFramebufferCount;
diff --git a/sc/source/ui/dbgui/tpsubt.cxx b/sc/source/ui/dbgui/tpsubt.cxx
index dc1ed43b0954..8ff412d68191 100644
--- a/sc/source/ui/dbgui/tpsubt.cxx
+++ b/sc/source/ui/dbgui/tpsubt.cxx
@@ -275,7 +275,7 @@ void ScTpSubTotalGroup::FillListBoxes()
             i++;
         }
         // subsequent initialization of the constant:
-        const_cast<sal_uInt16&>(nFieldCount) = i;
+        nFieldCount = i;
     }
 }
 
diff --git a/sc/source/ui/inc/tpsubt.hxx b/sc/source/ui/inc/tpsubt.hxx
index 8b2bfee98e15..a88d608fd92d 100644
--- a/sc/source/ui/inc/tpsubt.hxx
+++ b/sc/source/ui/inc/tpsubt.hxx
@@ -60,7 +60,7 @@ protected:
     const sal_uInt16            nWhichSubTotals;
     const ScSubTotalParam&  rSubTotalData;
     SCCOL                   nFieldArr[SC_MAXFIELDS];
-    const sal_uInt16            nFieldCount;
+    sal_uInt16              nFieldCount;
 
 private:
     void            Init            ();
diff --git a/sd/source/ui/sidebar/PreviewValueSet.cxx b/sd/source/ui/sidebar/PreviewValueSet.cxx
index c145cb25ef1b..429411e5a754 100644
--- a/sd/source/ui/sidebar/PreviewValueSet.cxx
+++ b/sd/source/ui/sidebar/PreviewValueSet.cxx
@@ -22,11 +22,12 @@
 
 namespace sd { namespace sidebar {
 
+static const int gnBorderWidth(3);
+static const int gnBorderHeight(3);
+
 PreviewValueSet::PreviewValueSet (vcl::Window* pParent)
     : ValueSet (pParent, WB_TABSTOP),
       maPreviewSize(10,10),
-      mnBorderWidth(3),
-      mnBorderHeight(3),
       mnMaxColumnCount(-1)
 {
     SetStyle (
@@ -88,7 +89,7 @@ sal_uInt16 PreviewValueSet::CalculateColumnCount (int nWidth) const
     int nColumnCount = 0;
     if (nWidth > 0)
     {
-        nColumnCount = nWidth / (maPreviewSize.Width() + 2*mnBorderWidth);
+        nColumnCount = nWidth / (maPreviewSize.Width() + 2*gnBorderWidth);
         if (nColumnCount < 1)
             nColumnCount = 1;
         else if (mnMaxColumnCount>0 && nColumnCount>mnMaxColumnCount)
@@ -116,7 +117,7 @@ sal_Int32 PreviewValueSet::GetPreferredHeight (sal_Int32 nWidth)
     int nRowCount (CalculateRowCount(CalculateColumnCount(nWidth)));
     int nItemHeight (maPreviewSize.Height());
 
-    return nRowCount * (nItemHeight + 2*mnBorderHeight);
+    return nRowCount * (nItemHeight + 2*gnBorderHeight);
 }
 
 } } // end of namespace sd::sidebar
diff --git a/sd/source/ui/sidebar/PreviewValueSet.hxx b/sd/source/ui/sidebar/PreviewValueSet.hxx
index 41d5a8fac54e..8cf4c17b9d7f 100644
--- a/sd/source/ui/sidebar/PreviewValueSet.hxx
+++ b/sd/source/ui/sidebar/PreviewValueSet.hxx
@@ -51,8 +51,6 @@ protected:
 private:
     Link<const MouseEvent&,void> maRightMouseClickHandler;
     Size maPreviewSize;
-    const int mnBorderWidth;
-    const int mnBorderHeight;
     const int mnMaxColumnCount;
 
     sal_uInt16 CalculateColumnCount (int nWidth) const;
diff --git a/sw/source/core/inc/frmtool.hxx b/sw/source/core/inc/frmtool.hxx
index ab4aaa90faeb..1da214488941 100644
--- a/sw/source/core/inc/frmtool.hxx
+++ b/sw/source/core/inc/frmtool.hxx
@@ -387,7 +387,6 @@ class SwOrderIter
 {
     const SwPageFrame *m_pPage;
     const SdrObject *m_pCurrent;
-    const bool m_bFlysOnly;
 
 public:
     SwOrderIter( const SwPageFrame *pPage );
diff --git a/sw/source/core/layout/frmtool.cxx b/sw/source/core/layout/frmtool.cxx
index da6d31b63d96..ed566d0dd1d9 100644
--- a/sw/source/core/layout/frmtool.cxx
+++ b/sw/source/core/layout/frmtool.cxx
@@ -2242,8 +2242,7 @@ SwBorderAttrs *SwBorderAttrAccess::Get()
 
 SwOrderIter::SwOrderIter( const SwPageFrame *pPg ) :
     m_pPage( pPg ),
-    m_pCurrent( nullptr ),
-    m_bFlysOnly( true )
+    m_pCurrent( nullptr )
 {
 }
 
@@ -2260,7 +2259,7 @@ void SwOrderIter::Top()
             for (SwAnchoredObject* i : *pObjs)
             {
                 const SdrObject* pObj = i->GetDrawObj();
-                if ( m_bFlysOnly && dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
+                if ( dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
                     continue;
                 sal_uInt32 nTmp = pObj->GetOrdNumDirect();
                 if ( nTmp >= nTopOrd )
@@ -2286,7 +2285,7 @@ const SdrObject *SwOrderIter::Bottom()
             for (SwAnchoredObject* i : *pObjs)
             {
                 const SdrObject* pObj = i->GetDrawObj();
-                if ( m_bFlysOnly && dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
+                if ( dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
                     continue;
                 sal_uInt32 nTmp = pObj->GetOrdNumDirect();
                 if ( nTmp < nBotOrd )
@@ -2314,7 +2313,7 @@ const SdrObject *SwOrderIter::Next()
             for (SwAnchoredObject* i : *pObjs)
             {
                 const SdrObject* pObj = i->GetDrawObj();
-                if ( m_bFlysOnly && dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
+                if ( dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
                     continue;
                 sal_uInt32 nTmp = pObj->GetOrdNumDirect();
                 if ( nTmp > nCurOrd && nTmp < nOrd )
@@ -2342,7 +2341,7 @@ void SwOrderIter::Prev()
             for (SwAnchoredObject* i : *pObjs)
             {
                 const SdrObject* pObj = i->GetDrawObj();
-                if ( m_bFlysOnly && dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
+                if ( dynamic_cast<const SwVirtFlyDrawObj*>( pObj) ==  nullptr )
                     continue;
                 sal_uInt32 nTmp = pObj->GetOrdNumDirect();
                 if ( nTmp < nCurOrd && nTmp >= nOrd )
diff --git a/uui/source/secmacrowarnings.cxx b/uui/source/secmacrowarnings.cxx
index 3030ab92520a..c8953b5977e6 100644
--- a/uui/source/secmacrowarnings.cxx
+++ b/uui/source/secmacrowarnings.cxx
@@ -69,7 +69,6 @@ MacroWarning::MacroWarning(weld::Window* pParent, bool _bWithSignatures)
     , mxEnableBtn(m_xBuilder->weld_button("ok"))
     , mxDisableBtn(m_xBuilder->weld_button("cancel"))
     , mpInfos                ( nullptr )
-    , mbSignedMode           ( true )
     , mbShowSignatures       ( _bWithSignatures )
     , mnActSecLevel          ( 0 )
 {
@@ -105,7 +104,7 @@ IMPL_LINK_NOARG(MacroWarning, ViewSignsBtnHdl, weld::Button&, void)
 
 IMPL_LINK_NOARG(MacroWarning, EnableBtnHdl, weld::Button&, void)
 {
-    if (mbSignedMode && mxAlwaysTrustCB->get_active())
+    if (mxAlwaysTrustCB->get_active())
     {   // insert path into trusted path list
         uno::Reference< security::XDocumentDigitalSignatures > xD(
             security::DocumentDigitalSignatures::createWithVersion(comphelper::getProcessComponentContext(), maODFVersion));
diff --git a/uui/source/secmacrowarnings.hxx b/uui/source/secmacrowarnings.hxx
index fbaf55751f5e..b5e3c9a450b9 100644
--- a/uui/source/secmacrowarnings.hxx
+++ b/uui/source/secmacrowarnings.hxx
@@ -46,7 +46,6 @@ private:
     OUString                                 maODFVersion;
     const css::uno::Sequence< css::security::DocumentSignatureInformation >*    mpInfos;
 
-    const bool          mbSignedMode;           // mode of dialog (signed / unsigned macros)
     const bool          mbShowSignatures;
     sal_Int32           mnActSecLevel;
 
diff --git a/vcl/backendtest/VisualBackendTest.cxx b/vcl/backendtest/VisualBackendTest.cxx
index 239f47bd7ead..07aa218cf137 100644
--- a/vcl/backendtest/VisualBackendTest.cxx
+++ b/vcl/backendtest/VisualBackendTest.cxx
@@ -105,7 +105,7 @@ class VisualBackendTestWindow : public WorkWindow
 private:
     Timer maUpdateTimer;
     std::vector<std::chrono::high_resolution_clock::time_point> mTimePoints;
-    unsigned char const mnNumberOfTests;
+    static constexpr unsigned char gnNumberOfTests = 6;
     unsigned char mnTest;
     bool mbAnimate;
     ScopedVclPtr<VirtualDevice> mpVDev;
@@ -113,9 +113,8 @@ private:
 public:
     VisualBackendTestWindow()
         : WorkWindow(nullptr, WB_APP | WB_STDWORK)
-        , mnNumberOfTests(6)
-        , mnTest(10 * mnNumberOfTests)
-        , mbAnimate(mnTest % mnNumberOfTests == mnNumberOfTests - 1)
+        , mnTest(10 * gnNumberOfTests)
+        , mbAnimate(mnTest % gnNumberOfTests == gnNumberOfTests - 1)
         , mpVDev(VclPtr<VirtualDevice>::Create())
     {
         maUpdateTimer.SetInvokeHandler(LINK(this, VisualBackendTestWindow, updateHdl));
@@ -145,7 +144,7 @@ public:
 
         if (nCode == KEY_BACKSPACE || nCode == KEY_SPACE)
         {
-            if (mnTest % mnNumberOfTests == mnNumberOfTests - 1)
+            if (mnTest % gnNumberOfTests == gnNumberOfTests - 1)
             {
                 mbAnimate = true;
                 maUpdateTimer.Start();
@@ -377,7 +376,7 @@ public:
 
     virtual void Paint(vcl::RenderContext& rRenderContext, const tools::Rectangle& /*rRect*/) override
     {
-        if (mnTest % mnNumberOfTests == mnNumberOfTests - 1)
+        if (mnTest % gnNumberOfTests == gnNumberOfTests - 1)
         {
             rRenderContext.SetBackground(Wallpaper(COL_GREEN));
 
@@ -449,23 +448,23 @@ public:
         tools::Rectangle aRectangle;
         size_t index = 0;
 
-        if (mnTest % mnNumberOfTests == 0)
+        if (mnTest % gnNumberOfTests == 0)
         {
             testRectangles(rRenderContext, nWidth, nHeight);
         }
-        else if (mnTest % mnNumberOfTests == 1)
+        else if (mnTest % gnNumberOfTests == 1)
         {
             testFilledRectangles(rRenderContext, nWidth, nHeight);
         }
-        else if (mnTest % mnNumberOfTests == 2)
+        else if (mnTest % gnNumberOfTests == 2)
         {
             testLines(rRenderContext, nWidth, nHeight);
         }
-        else if (mnTest % mnNumberOfTests == 3)
+        else if (mnTest % gnNumberOfTests == 3)
         {
             testBitmaps(rRenderContext, nWidth, nHeight);
         }
-        else if (mnTest % mnNumberOfTests == 4)
+        else if (mnTest % gnNumberOfTests == 4)
         {
             std::vector<tools::Rectangle> aRegions = setupRegions(3, 2, nWidth, nHeight);
 
diff --git a/vcl/inc/unx/glyphcache.hxx b/vcl/inc/unx/glyphcache.hxx
index 38e63cbd9b1e..9d0be13e3a6d 100644
--- a/vcl/inc/unx/glyphcache.hxx
+++ b/vcl/inc/unx/glyphcache.hxx
@@ -88,7 +88,7 @@ private:
     typedef std::unordered_map<rtl::Reference<LogicalFontInstance>,std::unique_ptr<FreetypeFont>,IFSD_Hash,IFSD_Equal > FontList;
 
     FontList                maFontList;
-    sal_uLong const         mnMaxSize;      // max overall cache size in bytes
+    static constexpr sal_uLong gnMaxSize = 1500000;  // max overall cache size in bytes
     mutable sal_uLong       mnBytesUsed;
     mutable long            mnLruIndex;
     mutable int             mnGlyphCount;
diff --git a/vcl/opengl/win/gdiimpl.cxx b/vcl/opengl/win/gdiimpl.cxx
index 0c622bb51d85..58ec8f730c29 100644
--- a/vcl/opengl/win/gdiimpl.cxx
+++ b/vcl/opengl/win/gdiimpl.cxx
@@ -529,9 +529,7 @@ bool WinOpenGLContext::ImplInit()
         0, 0, 0                         // Layer Masks Ignored
     };
 
-    if (mbUseDoubleBufferedRendering)
-        PixelFormatFront.dwFlags |= PFD_DOUBLEBUFFER;
-
+    PixelFormatFront.dwFlags |= PFD_DOUBLEBUFFER;
     PixelFormatFront.dwFlags |= PFD_DRAW_TO_WINDOW;
 
     //  we must check whether can set the MSAA
@@ -539,7 +537,7 @@ bool WinOpenGLContext::ImplInit()
     bool bMultiSampleSupport = false;
 
     if (!mbVCLOnly)
-        bMultiSampleSupport = InitMultisample(PixelFormatFront, WindowPix, mbUseDoubleBufferedRendering, false);
+        bMultiSampleSupport = InitMultisample(PixelFormatFront, WindowPix, /*bUseDoubleBufferedRendering*/true, false);
     else
         VCL_GL_INFO("Skipping multisample detection for VCL.");
 
diff --git a/vcl/opengl/x11/gdiimpl.cxx b/vcl/opengl/x11/gdiimpl.cxx
index 6f230ce81360..98eb604fd1b3 100644
--- a/vcl/opengl/x11/gdiimpl.cxx
+++ b/vcl/opengl/x11/gdiimpl.cxx
@@ -302,7 +302,7 @@ bool X11OpenGLContext::ImplInit()
     if (hasCreateContextAttribsARB && !mbRequestLegacyContext)
     {
         int best_fbc = -1;
-        GLXFBConfig* pFBC = getFBConfig(m_aGLWin.dpy, m_aGLWin.win, best_fbc, mbUseDoubleBufferedRendering);
+        GLXFBConfig* pFBC = getFBConfig(m_aGLWin.dpy, m_aGLWin.win, best_fbc, /*bUseDoubleBufferedRendering*/true);
 
         if (pFBC && best_fbc != -1)
         {
diff --git a/vcl/source/gdi/pdfwriter_impl.cxx b/vcl/source/gdi/pdfwriter_impl.cxx
index 1a3e67d366d7..ef04535ba2c4 100644
--- a/vcl/source/gdi/pdfwriter_impl.cxx
+++ b/vcl/source/gdi/pdfwriter_impl.cxx
@@ -1690,8 +1690,6 @@ void PDFWriterImpl::PDFPage::appendWaveLine( sal_Int32 nWidth, sal_Int32 nY, sal
         m_nCurrentStructElement( 0 ),
         m_bEmitStructure( true ),
         m_nNextFID( 1 ),
-        m_nInheritedPageWidth( 595 ),  // default A4
-        m_nInheritedPageHeight( 842 ), // default A4
         m_nCurrentPage( -1 ),
         m_nCatalogObject(0),
         m_nSignatureObject( -1 ),
@@ -4992,8 +4990,8 @@ bool PDFWriterImpl::emitCatalog()
     sal_Int32 nMediaBoxHeight = 0;
     if( m_aPages.empty() ) // sanity check, this should not happen
     {
-        nMediaBoxWidth = m_nInheritedPageWidth;
-        nMediaBoxHeight = m_nInheritedPageHeight;
+        nMediaBoxWidth = g_nInheritedPageWidth;
+        nMediaBoxHeight = g_nInheritedPageHeight;
     }
     else
     {
@@ -5109,14 +5107,14 @@ bool PDFWriterImpl::emitCatalog()
         aLine.append( "/OpenAction[" );
         aLine.append( aInitPageRef.makeStringAndClear() );
         aLine.append( " /FitH " );
-        aLine.append( m_nInheritedPageHeight );//Open fit width
+        aLine.append( g_nInheritedPageHeight );//Open fit width
         aLine.append( "]\n" );
         break;
     case PDFWriter::FitVisible :
         aLine.append( "/OpenAction[" );
         aLine.append( aInitPageRef.makeStringAndClear() );
         aLine.append( " /FitBH " );
-        aLine.append( m_nInheritedPageHeight );//Open fit visible
+        aLine.append( g_nInheritedPageHeight );//Open fit visible
         aLine.append( "]\n" );
         break;
     case PDFWriter::ActionZoom :
diff --git a/vcl/source/gdi/pdfwriter_impl.hxx b/vcl/source/gdi/pdfwriter_impl.hxx
index 3656fe50ceca..e18860592ecb 100644
--- a/vcl/source/gdi/pdfwriter_impl.hxx
+++ b/vcl/source/gdi/pdfwriter_impl.hxx
@@ -188,7 +188,7 @@ public:
         // appends a horizontal waveline with vertical offset (helper for drawWaveLine)
         void appendWaveLine( sal_Int32 nLength, sal_Int32 nYOffset, sal_Int32 nDelta, OStringBuffer& rBuffer ) const;
 
-        double getHeight() const { return m_nPageHeight ? m_nPageHeight : m_pWriter->m_nInheritedPageHeight; }
+        double getHeight() const { return m_nPageHeight ? m_nPageHeight : PDFWriterImpl::g_nInheritedPageHeight; }
     };
 
     friend struct PDFPage;
@@ -693,8 +693,8 @@ private:
     sal_Int32                           m_nNextFID;
     PDFFontCache                        m_aFontCache;
 
-    sal_Int32 const                           m_nInheritedPageWidth;  // in inch/72
-    sal_Int32 const                           m_nInheritedPageHeight; // in inch/72
+    static constexpr sal_Int32          g_nInheritedPageWidth = 595;  // default A4 in inch/72
+    static constexpr sal_Int32          g_nInheritedPageHeight = 842; // default A4 in inch/72
     sal_Int32                           m_nCurrentPage;
 
     sal_Int32                           m_nCatalogObject;
diff --git a/vcl/source/opengl/OpenGLContext.cxx b/vcl/source/opengl/OpenGLContext.cxx
index 875589e00df1..07f5491a11c9 100644
--- a/vcl/source/opengl/OpenGLContext.cxx
+++ b/vcl/source/opengl/OpenGLContext.cxx
@@ -55,7 +55,6 @@ OpenGLContext::OpenGLContext():
     mbInitialized(false),
     mnRefCount(0),
     mbRequestLegacyContext(false),
-    mbUseDoubleBufferedRendering(true),
     mbVCLOnly(false),
     mnFramebufferCount(0),
     mpCurrentFramebuffer(nullptr),
diff --git a/vcl/unx/generic/glyphs/glyphcache.cxx b/vcl/unx/generic/glyphs/glyphcache.cxx
index c802df0e3cc0..3ce24ece848c 100644
--- a/vcl/unx/generic/glyphs/glyphcache.cxx
+++ b/vcl/unx/generic/glyphs/glyphcache.cxx
@@ -33,8 +33,7 @@
 static GlyphCache* pInstance = nullptr;
 
 GlyphCache::GlyphCache()
-:   mnMaxSize( 1500000 ),
-    mnBytesUsed(sizeof(GlyphCache)),
+:   mnBytesUsed(sizeof(GlyphCache)),
     mnLruIndex(0),
     mnGlyphCount(0),
     mpCurrentGCFont(nullptr)
@@ -226,7 +225,7 @@ FreetypeFont* GlyphCache::CacheFont(LogicalFontInstance* pFontInstance)
 
 void GlyphCache::UncacheFont( FreetypeFont& rFreetypeFont )
 {
-    if( (rFreetypeFont.Release() <= 0) && (mnMaxSize <= mnBytesUsed) )
+    if( (rFreetypeFont.Release() <= 0) && (gnMaxSize <= mnBytesUsed) )
     {
         mpCurrentGCFont = &rFreetypeFont;
         GarbageCollect();
@@ -290,7 +289,7 @@ inline void GlyphCache::AddedGlyph( GlyphData& rGlyphData )
     ++mnGlyphCount;
     mnBytesUsed += sizeof( rGlyphData );
     UsingGlyph( rGlyphData );
-    if( mnBytesUsed > mnMaxSize )
+    if( mnBytesUsed > gnMaxSize )
         GarbageCollect();
 }
 
diff --git a/vcl/unx/generic/print/bitmap_gfx.cxx b/vcl/unx/generic/print/bitmap_gfx.cxx
index b34bdfd511d9..04ce1fd3ba96 100644
--- a/vcl/unx/generic/print/bitmap_gfx.cxx
+++ b/vcl/unx/generic/print/bitmap_gfx.cxx
@@ -277,7 +277,7 @@ private:
     std::array<LZWCTreeNode, 4096>
                     mpTable;    // LZW compression data
     LZWCTreeNode*   mpPrefix;   // the compression is as same as the TIFF compression
-    sal_uInt16 const mnDataSize;
+    static constexpr sal_uInt16 gnDataSize = 8;
     sal_uInt16 const mnClearCode;
     sal_uInt16 const mnEOICode;
     sal_uInt16      mnTableSize;
@@ -298,11 +298,10 @@ public:
 LZWEncoder::LZWEncoder(osl::File* pOutputFile) :
         Ascii85Encoder (pOutputFile),
         mpPrefix(nullptr),
-        mnDataSize(8),
-        mnClearCode(1 << mnDataSize),
+        mnClearCode(1 << gnDataSize),
         mnEOICode(mnClearCode + 1),
         mnTableSize(mnEOICode + 1),
-        mnCodeSize(mnDataSize + 1),
+        mnCodeSize(gnDataSize + 1),
         mnOffset(32),       // free bits in dwShift
         mdwShift(0)
 {
@@ -375,7 +374,7 @@ LZWEncoder::EncodeByte (sal_uInt8 nByte )
                 for (i = 0; i < mnClearCode; i++)
                     mpTable[i].mpFirstChild = nullptr;
 
-                mnCodeSize = mnDataSize + 1;
+                mnCodeSize = gnDataSize + 1;
                 mnTableSize = mnEOICode + 1;
             }
             else
diff --git a/vcl/unx/gtk/fpicker/SalGtkFilePicker.cxx b/vcl/unx/gtk/fpicker/SalGtkFilePicker.cxx
index f3e8e1ab7f39..016c3d6cf49f 100644
--- a/vcl/unx/gtk/fpicker/SalGtkFilePicker.cxx
+++ b/vcl/unx/gtk/fpicker/SalGtkFilePicker.cxx
@@ -90,9 +90,7 @@ SalGtkFilePicker::SalGtkFilePicker( const uno::Reference< uno::XComponentContext
     mbPreviewState( false ),
     mHID_Preview( 0 ),
     m_pPreview( nullptr ),
-    m_pPseudoFilter( nullptr ),
-    m_PreviewImageWidth( 256 ),
-    m_PreviewImageHeight( 256 )
+    m_pPseudoFilter( nullptr )
 {
     int i;
 
@@ -1414,7 +1412,7 @@ sal_Int32 SAL_CALL SalGtkFilePicker::getAvailableWidth()
 
     OSL_ASSERT( m_pDialog != nullptr );
 
-    return m_PreviewImageWidth;
+    return g_PreviewImageWidth;
 }
 
 sal_Int32 SAL_CALL SalGtkFilePicker::getAvailableHeight()
@@ -1423,7 +1421,7 @@ sal_Int32 SAL_CALL SalGtkFilePicker::getAvailableHeight()
 
     OSL_ASSERT( m_pDialog != nullptr );
 
-    return m_PreviewImageHeight;
+    return g_PreviewImageHeight;
 }
 
 void SAL_CALL SalGtkFilePicker::setImage( sal_Int16 /*aImageFormat*/, const uno::Any& /*aImage*/ )
@@ -1509,8 +1507,8 @@ void SalGtkFilePicker::update_preview_cb( GtkFileChooser *file_chooser, SalGtkFi
     {
         pixbuf = gdk_pixbuf_new_from_file_at_size(
                 filename,
-                pobjFP->m_PreviewImageWidth,
-                pobjFP->m_PreviewImageHeight, nullptr );
+                g_PreviewImageWidth,
+                g_PreviewImageHeight, nullptr );
 
         have_preview = ( pixbuf != nullptr );
 
diff --git a/vcl/unx/gtk/fpicker/SalGtkFilePicker.hxx b/vcl/unx/gtk/fpicker/SalGtkFilePicker.hxx
index d5db18d6fcf4..d6265702f314 100644
--- a/vcl/unx/gtk/fpicker/SalGtkFilePicker.hxx
+++ b/vcl/unx/gtk/fpicker/SalGtkFilePicker.hxx
@@ -202,8 +202,8 @@ class SalGtkFilePicker : public SalGtkPicker, public SalGtkFilePicker_Base
         gulong mHID_Preview;
         GtkWidget* m_pPreview;
         GtkFileFilter* m_pPseudoFilter;
-        sal_Int32 const m_PreviewImageWidth;
-        sal_Int32 const m_PreviewImageHeight;
+        static constexpr sal_Int32 g_PreviewImageWidth = 256;
+        static constexpr sal_Int32 g_PreviewImageHeight = 256;
 
         GtkWidget  *getWidget( sal_Int16 nControlId, GType *pType = nullptr);
 
diff --git a/writerfilter/source/dmapper/GraphicImport.cxx b/writerfilter/source/dmapper/GraphicImport.cxx
index 2df49c4dbe57..d0dbb8fd4463 100644
--- a/writerfilter/source/dmapper/GraphicImport.cxx
+++ b/writerfilter/source/dmapper/GraphicImport.cxx
@@ -200,7 +200,7 @@ public:
     sal_Int32 nBrightness;
     double const    fGamma;
 
-    sal_Int32 const nFillColor;
+    static constexpr sal_Int32 nFillColor = 0xffffffff;
 
     drawing::ColorMode eColorMode;
 
@@ -260,7 +260,6 @@ public:
         ,nContrast(0)
         ,nBrightness(0)
         ,fGamma( -1.0 )
-        ,nFillColor( 0xffffffff )
         ,eColorMode( drawing::ColorMode_STANDARD )
         ,nCurrentBorderLine(BORDER_TOP)
         ,bIsGraphic(false)
@@ -388,6 +387,10 @@ public:
     }
 };
 
+#if !HAVE_CPP_INLINE_VARIABLES
+constexpr sal_Int32 GraphicImport_Impl::nFillColor;
+#endif
+
 GraphicImport::GraphicImport(uno::Reference<uno::XComponentContext> const& xComponentContext,
                              uno::Reference<lang::XMultiServiceFactory> const& xTextFactory,
                              DomainMapper& rDMapper,
@@ -1276,7 +1279,7 @@ uno::Reference<text::XTextContent> GraphicImport::createGraphicObject(uno::Refer
                     uno::makeAny(m_pImpl->fGamma ));
 
             xGraphicObjectProperties->setPropertyValue(getPropertyName( PROP_BACK_COLOR ),
-                uno::makeAny( m_pImpl->nFillColor ));
+                uno::makeAny( GraphicImport_Impl::nFillColor ));
 
             m_pImpl->applyZOrder(xGraphicObjectProperties);