Extend loplugin:external to warn about classes

...following up on 314f15bff08b76bf96acf99141776ef64d2f1355 "Extend
loplugin:external to warn about enums".

Cases where free functions were moved into an unnamed namespace along with a
class, to not break ADL, are in:

filter/source/svg/svgexport.cxx
sc/source/filter/excel/xelink.cxx
sc/source/filter/excel/xilink.cxx
svx/source/sdr/contact/viewobjectcontactofunocontrol.cxx

All other free functions mentioning moved classes appear to be harmless and not
give rise to (silent, even) ADL breakage.  (One remaining TODO in
compilerplugins/clang/external.cxx is that derived classes are not covered by
computeAffectedTypes, even though they could also be affected by ADL-breakage---
but don't seem to be in any acutal case across the code base.)

For friend declarations using elaborate type specifiers, like

class C1 {};
class C2 { friend class C1; };

* If C2 (but not C1) is moved into an unnamed namespace, the friend declaration
must be changed to not use an elaborate type specifier (i.e., "friend C1;"; see
C++17 [namespace.memdef]/3: "If the name in a friend declaration is neither
qualified nor a template-id and the declaration is a function or an
elaborated-type-specifier, the lookup to determine whether the entity has been
previously declared shall not consider any scopes outside the innermost
enclosing namespace.")

* If C1 (but not C2) is moved into an unnamed namespace, the friend declaration
must be changed too, see <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71882>
"elaborated-type-specifier friend not looked up in unnamed namespace".

Apart from that, to keep changes simple and mostly mechanical (which should help
avoid regressions), out-of-line definitions of class members have been left in
the enclosing (named) namespace.  But explicit specializations of class
templates had to be moved into the unnamed namespace to appease
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92598> "explicit specialization of
template from unnamed namespace using unqualified-id in enclosing namespace".

Also, accompanying declarations (of e.g. typedefs or static variables) that
could arguably be moved into the unnamed namespace too have been left alone.

And in some cases, mention of affected types in blacklists in other loplugins
needed to be adapted.

And sc/qa/unit/mark_test.cxx uses a hack of including other .cxx, one of which
is sc/source/core/data/segmenttree.cxx where e.g. ScFlatUInt16SegmentsImpl is
not moved into an unnamed namespace (because it is declared in
sc/inc/segmenttree.hxx), but its base ScFlatSegmentsImpl is.  GCC warns about
such combinations with enabled-by-default -Wsubobject-linkage, but "The compiler
doesn’t give this warning for types defined in the main .C file, as those are
unlikely to have multiple definitions."
(<https://gcc.gnu.org/onlinedocs/gcc-9.2.0/gcc/Warning-Options.html>)  The
warned-about classes also don't have multiple definitions in the given test, so
disable the warning when including the .cxx.

Change-Id: Ib694094c0d8168be68f8fe90dfd0acbb66a3f1e4
Reviewed-on: https://gerrit.libreoffice.org/83239
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

12 files changed, 53 insertions, 0 deletions

diff --git a/sfx2/source/appl/appcfg.cxx b/sfx2/source/appl/appcfg.cxx
index 208c23aca8b5..8b9ca9e6f413 100644
--- a/sfx2/source/appl/appcfg.cxx
+++ b/sfx2/source/appl/appcfg.cxx
@@ -76,6 +76,7 @@ using namespace ::com::sun::star::uno;
 using namespace ::com::sun::star::util;
 using namespace ::com::sun::star::beans;
 
+namespace {
 
 class SfxEventAsyncer_Impl : public SfxListener
 {
@@ -89,6 +90,7 @@ public:
     DECL_LINK( IdleHdl, Timer*, void );
 };
 
+}
 
 void SfxEventAsyncer_Impl::Notify( SfxBroadcaster&, const SfxHint& rHint )
 {
diff --git a/sfx2/source/appl/appinit.cxx b/sfx2/source/appl/appinit.cxx
index 3b2234e8545b..68ee31f76b89 100644
--- a/sfx2/source/appl/appinit.cxx
+++ b/sfx2/source/appl/appinit.cxx
@@ -72,6 +72,8 @@ using namespace ::com::sun::star::frame;
 using namespace ::com::sun::star::lang;
 using namespace ::com::sun::star;
 
+namespace {
+
 class SfxTerminateListener_Impl : public ::cppu::WeakImplHelper< XTerminateListener, XServiceInfo >
 {
 public:
@@ -87,6 +89,8 @@ public:
     virtual css::uno::Sequence< OUString > SAL_CALL getSupportedServiceNames() override;
 };
 
+}
+
 void SAL_CALL SfxTerminateListener_Impl::disposing( const EventObject& )
 {
 }
diff --git a/sfx2/source/appl/appopen.cxx b/sfx2/source/appl/appopen.cxx
index 5ef87f45cc91..5f6fb65c3684 100644
--- a/sfx2/source/appl/appopen.cxx
+++ b/sfx2/source/appl/appopen.cxx
@@ -117,6 +117,7 @@ void SetTemplate_Impl( const OUString &rFileName,
     pDoc->ResetFromTemplate( rLongName, rFileName );
 }
 
+namespace {
 
 class SfxDocPasswordVerifier : public ::comphelper::IDocPasswordVerifier
 {
@@ -134,6 +135,7 @@ private:
     Reference< embed::XStorage > mxStorage;
 };
 
+}
 
 ::comphelper::DocPasswordVerifierResult SfxDocPasswordVerifier::verifyPassword( const OUString& rPassword, uno::Sequence< beans::NamedValue >& o_rEncryptionData )
 {
diff --git a/sfx2/source/appl/childwin.cxx b/sfx2/source/appl/childwin.cxx
index a7013fa6c530..602b24967d5c 100644
--- a/sfx2/source/appl/childwin.cxx
+++ b/sfx2/source/appl/childwin.cxx
@@ -64,6 +64,7 @@ struct SfxChildWindow_Impl
     SfxWorkWindow*      pWorkWin;
 };
 
+namespace {
 
 class DisposeListener : public ::cppu::WeakImplHelper< css::lang::XEventListener >
 {
@@ -107,6 +108,7 @@ class DisposeListener : public ::cppu::WeakImplHelper< css::lang::XEventListener
         SfxChildWindow_Impl* m_pData ;
 };
 
+}
 
 bool GetPosSizeFromString( const OUString& rStr, Point& rPos, Size& rSize )
 {
diff --git a/sfx2/source/appl/impldde.cxx b/sfx2/source/appl/impldde.cxx
index 25097d480440..39cd6629b12a 100644
--- a/sfx2/source/appl/impldde.cxx
+++ b/sfx2/source/appl/impldde.cxx
@@ -47,6 +47,8 @@ using namespace ::com::sun::star::uno;
 namespace sfx2
 {
 
+namespace {
+
 class SvDDELinkEditDialog : public weld::GenericDialogController
 {
     std::unique_ptr<weld::Entry> m_xEdDdeApp;
@@ -60,6 +62,8 @@ public:
     OUString GetCmd() const;
 };
 
+}
+
 SvDDELinkEditDialog::SvDDELinkEditDialog(weld::Window* pParent, SvBaseLink const * pLink)
     : GenericDialogController(pParent, "sfx/ui/linkeditdialog.ui", "LinkEditDialog")
     , m_xEdDdeApp(m_xBuilder->weld_entry("app"))
diff --git a/sfx2/source/appl/linkmgr2.cxx b/sfx2/source/appl/linkmgr2.cxx
index 4f9c109a23d1..fb8746e834fd 100644
--- a/sfx2/source/appl/linkmgr2.cxx
+++ b/sfx2/source/appl/linkmgr2.cxx
@@ -60,6 +60,8 @@ using ::com::sun::star::util::XCloseable;
 namespace sfx2
 {
 
+namespace {
+
 class SvxInternalLink : public sfx2::SvLinkSource
 {
 public:
@@ -68,6 +70,8 @@ public:
     virtual bool Connect( sfx2::SvBaseLink* ) override;
 };
 
+}
+
 LinkManager::LinkManager(SfxObjectShell* p)
     : pPersist( p )
 {
diff --git a/sfx2/source/appl/linksrc.cxx b/sfx2/source/appl/linksrc.cxx
index 98c347713dfb..9bfab2bfa4d8 100644
--- a/sfx2/source/appl/linksrc.cxx
+++ b/sfx2/source/appl/linksrc.cxx
@@ -33,6 +33,7 @@ using namespace ::com::sun::star::uno;
 namespace sfx2
 {
 
+namespace {
 
 class SvLinkSourceTimer : public Timer
 {
@@ -42,6 +43,8 @@ public:
     explicit SvLinkSourceTimer( SvLinkSource * pOwn );
 };
 
+}
+
 SvLinkSourceTimer::SvLinkSourceTimer( SvLinkSource * pOwn )
     : pOwner( pOwn )
 {
@@ -65,6 +68,7 @@ static void StartTimer( std::unique_ptr<SvLinkSourceTimer>& pTimer, SvLinkSource
     }
 }
 
+namespace {
 
 struct SvLinkSource_Entry_Impl
 {
@@ -119,6 +123,8 @@ public:
     bool IsValidCurrValue( SvLinkSource_Entry_Impl const * pEntry );
 };
 
+}
+
 SvLinkSource_EntryIter_Impl::SvLinkSource_EntryIter_Impl(
         const SvLinkSource_Array_Impl& rArr )
     : rOrigArr( rArr ), nPos( 0 )
diff --git a/sfx2/source/appl/lnkbase2.cxx b/sfx2/source/appl/lnkbase2.cxx
index 9d234bf82c81..ab0119053021 100644
--- a/sfx2/source/appl/lnkbase2.cxx
+++ b/sfx2/source/appl/lnkbase2.cxx
@@ -40,9 +40,12 @@ using namespace ::com::sun::star::uno;
 namespace sfx2
 {
 
+namespace {
 
 class  ImplDdeItem;
 
+}
+
 struct BaseLink_Impl
 {
     Link<SvBaseLink&,void> m_aEndEditLink;
@@ -89,6 +92,7 @@ struct ImplBaseLinkData
     }
 };
 
+namespace {
 
 class ImplDdeItem : public DdeGetPutItem
 {
@@ -119,6 +123,7 @@ public:
     bool IsInDTOR() const { return bIsInDTOR; }
 };
 
+}
 
 SvBaseLink::SvBaseLink()
     : pImpl ( new BaseLink_Impl ),
diff --git a/sfx2/source/appl/newhelp.cxx b/sfx2/source/appl/newhelp.cxx
index c34308afb72d..945d24a1f63b 100644
--- a/sfx2/source/appl/newhelp.cxx
+++ b/sfx2/source/appl/newhelp.cxx
@@ -243,6 +243,8 @@ namespace sfx2
 
 // struct IndexEntry_Impl ------------------------------------------------
 
+namespace {
+
 struct IndexEntry_Impl
 {
     bool const        m_bSubEntry;
@@ -263,6 +265,8 @@ struct ContentEntry_Impl
         aURL( rURL ), bIsFolder( bFolder ) {}
 };
 
+}
+
 // ContentListBox_Impl ---------------------------------------------------
 
 ContentListBox_Impl::ContentListBox_Impl(vcl::Window* pParent, WinBits nStyle)
diff --git a/sfx2/source/appl/openuriexternally.cxx b/sfx2/source/appl/openuriexternally.cxx
index c0a14425ebc8..45e9ee0861f4 100644
--- a/sfx2/source/appl/openuriexternally.cxx
+++ b/sfx2/source/appl/openuriexternally.cxx
@@ -31,6 +31,8 @@
 #include <sfx2/viewsh.hxx>
 #include <sfx2/strings.hrc>
 
+namespace {
+
 class URITools
 {
 private:
@@ -47,6 +49,8 @@ public:
     void openURI(const OUString& sURI, bool bHandleSystemShellExecuteException);
 };
 
+}
+
 void URITools::openURI(const OUString& sURI, bool bHandleSystemShellExecuteException)
 {
     if (comphelper::LibreOfficeKit::isActive())
diff --git a/sfx2/source/appl/sfxhelp.cxx b/sfx2/source/appl/sfxhelp.cxx
index c4c1735f6418..2158acdcc7fd 100644
--- a/sfx2/source/appl/sfxhelp.cxx
+++ b/sfx2/source/appl/sfxhelp.cxx
@@ -102,6 +102,8 @@ using namespace ::com::sun::star::util;
 using namespace ::com::sun::star::lang;
 using namespace ::com::sun::star::system;
 
+namespace {
+
 class NoHelpErrorBox
 {
 private:
@@ -122,6 +124,8 @@ public:
     }
 };
 
+}
+
 IMPL_STATIC_LINK_NOARG(NoHelpErrorBox, HelpRequestHdl, weld::Widget&, bool)
 {
     // do nothing, because no help available
@@ -329,12 +333,16 @@ static bool GetHelpAnchor_Impl( const OUString& _rURL, OUString& _rAnchor )
     return bRet;
 }
 
+namespace {
+
 class SfxHelp_Impl
 {
 public:
     static OUString GetHelpText( const OUString& aCommandURL, const OUString& rModule );
 };
 
+}
+
 OUString SfxHelp_Impl::GetHelpText( const OUString& aCommandURL, const OUString& rModule )
 {
     // create help url
@@ -994,6 +1002,8 @@ namespace
     }
 }
 
+namespace {
+
 class HelpManualMessage : public weld::MessageDialogController
 {
 private:
@@ -1013,6 +1023,8 @@ public:
     bool GetOfflineHelpPopUp() const { return !m_xHideOfflineHelpCB->get_active(); }
 };
 
+}
+
 bool SfxHelp::Start_Impl(const OUString& rURL, const vcl::Window* pWindow, const OUString& rKeyword)
 {
     OUStringBuffer aHelpRootURL("vnd.sun.star.help://");
diff --git a/sfx2/source/appl/workwin.cxx b/sfx2/source/appl/workwin.cxx
index 5feb326243fc..f372857c286a 100644
--- a/sfx2/source/appl/workwin.cxx
+++ b/sfx2/source/appl/workwin.cxx
@@ -63,12 +63,16 @@
 using namespace ::com::sun::star;
 using namespace ::com::sun::star::uno;
 
+namespace {
+
 struct ResIdToResName
 {
     ToolbarId const   eId;
     const char* pName;
 };
 
+}
+
 static const ResIdToResName pToolBarResToName[] =
 {
     { ToolbarId::FullScreenToolbox,       "fullscreenbar"        },