New loplugin:external

...warning about (for now only) functions and variables with external linkage
that likely don't need it.

The problems with moving entities into unnamed namespacs and breaking ADL
(as alluded to in comments in compilerplugins/clang/external.cxx) are
illustrated by the fact that while

  struct S1 { int f() { return 0; } };
  int f(S1 s) { return s.f(); }
  namespace N {
    struct S2: S1 { int f() { return 1; } };
    int f(S2 s) { return s.f(); }
  }
  int main() { return f(N::S2()); }

returns 1, both moving just the struct S2 into an nunnamed namespace,

  struct S1 { int f() { return 0; } };
  int f(S1 s) { return s.f(); }
  namespace N {
    namespace { struct S2: S1 { int f() { return 1; } }; }
    int f(S2 s) { return s.f(); }
  }
  int main() { return f(N::S2()); }

as well as moving just the function f overload into an unnamed namespace,

  struct S1 { int f() { return 0; } };
  int f(S1 s) { return s.f(); }
  namespace N {
    struct S2: S1 { int f() { return 1; } };
    namespace { int f(S2 s) { return s.f(); } }
  }
  int main() { return f(N::S2()); }

would each change the program to return 0 instead.

Change-Id: I4d09f7ac5e8f9bcd6e6bde4712608444b642265c
Reviewed-on: https://gerrit.libreoffice.org/60539
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

3 files changed, 4 insertions, 4 deletions

diff --git a/lotuswordpro/source/filter/bencont.cxx b/lotuswordpro/source/filter/bencont.cxx
index 19c7a446eaba..cb2f97f9d924 100644
--- a/lotuswordpro/source/filter/bencont.cxx
+++ b/lotuswordpro/source/filter/bencont.cxx
@@ -246,7 +246,7 @@ LtcUtBenValueStream * LtcBenContainer::FindValueStreamWithPropertyName(const cha
     return FindNextValueStreamWithPropertyName(sPropertyName);
 }
 
-sal_uInt64 GetSvStreamSize(SvStream * pStream)
+static sal_uInt64 GetSvStreamSize(SvStream * pStream)
 {
     sal_uInt64 nCurPos = pStream->Tell();
     pStream->Seek(STREAM_SEEK_TO_END);
diff --git a/lotuswordpro/source/filter/lwpfilter.cxx b/lotuswordpro/source/filter/lwpfilter.cxx
index a6ac2ee17caa..afab92eb24ea 100644
--- a/lotuswordpro/source/filter/lwpfilter.cxx
+++ b/lotuswordpro/source/filter/lwpfilter.cxx
@@ -98,7 +98,7 @@ using namespace ::com::sun::star;
 #include "bento.hxx"
 using namespace OpenStormBento;
 #include "explode.hxx"
-bool Decompress(SvStream *pCompressed, SvStream * & pOutDecompressed)
+static bool Decompress(SvStream *pCompressed, SvStream * & pOutDecompressed)
 {
     pCompressed->Seek(0);
     std::unique_ptr<SvMemoryStream> aDecompressed(new SvMemoryStream(4096, 4096));
@@ -148,7 +148,7 @@ bool Decompress(SvStream *pCompressed, SvStream * & pOutDecompressed)
  * @param    LwpSvStream * , created inside, deleted outside
  * @param      sal_Bool, sal_True -
  */
- bool GetLwpSvStream(SvStream *pStream, LwpSvStream * & pLwpSvStream)
+static bool GetLwpSvStream(SvStream *pStream, LwpSvStream * & pLwpSvStream)
 {
     SvStream * pDecompressed = nullptr;
 
diff --git a/lotuswordpro/source/filter/xfilter/xfbase64.cxx b/lotuswordpro/source/filter/xfilter/xfbase64.cxx
index 0a388f7b6a47..226541bf2659 100644
--- a/lotuswordpro/source/filter/xfilter/xfbase64.cxx
+++ b/lotuswordpro/source/filter/xfilter/xfbase64.cxx
@@ -72,7 +72,7 @@ const  sal_Char aBase64EncodeTable[] =
  * @descr   Encode 3 byte to 4 byte.
  *          Please refer to RFC to get the base64 algorithm.
  */
-inline void Encode_(const sal_uInt8 *src, sal_Char* dest)
+static inline void Encode_(const sal_uInt8 *src, sal_Char* dest)
 {
     sal_Int32 nBinaer = (src[ 0] << 16) +
         (src[1] <<  8) +