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>

2 files changed, 3 insertions, 3 deletions

diff --git a/sax/source/tools/converter.cxx b/sax/source/tools/converter.cxx
index 79f84c09697e..741dcc8b086c 100644
--- a/sax/source/tools/converter.cxx
+++ b/sax/source/tools/converter.cxx
@@ -475,7 +475,7 @@ void Converter::convertMeasurePx( OUStringBuffer& rBuffer, sal_Int32 nValue )
     rBuffer.append( 'x' );
 }
 
-int lcl_gethex( int nChar )
+static int lcl_gethex( int nChar )
 {
     if( nChar >= '0' && nChar <= '9' )
         return nChar - '0';
diff --git a/sax/source/tools/fastserializer.cxx b/sax/source/tools/fastserializer.cxx
index 9356f3e081d1..b232d0b3abf0 100644
--- a/sax/source/tools/fastserializer.cxx
+++ b/sax/source/tools/fastserializer.cxx
@@ -105,7 +105,7 @@ namespace sax_fastparser {
     /** Characters not allowed in XML 1.0
         XML 1.1 would exclude only U+0000
      */
-    bool invalidChar( char c )
+    static bool invalidChar( char c )
     {
         if (static_cast<unsigned char>(c) >= 0x20)
             return false;
@@ -120,7 +120,7 @@ namespace sax_fastparser {
         return true;
     }
 
-    bool isHexDigit( char c )
+    static bool isHexDigit( char c )
     {
         return ('0' <= c && c <= '9') || ('A' <= c && c <= 'F') || ('a' <= c && c <= 'f');
     }