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>

1 files changed, 8 insertions, 8 deletions

diff --git a/xmlsecurity/source/xmlsec/xmlstreamio.cxx b/xmlsecurity/source/xmlsec/xmlstreamio.cxx
index 7cd44219d2f5..be48ae34b232 100644
--- a/xmlsecurity/source/xmlsec/xmlstreamio.cxx
+++ b/xmlsecurity/source/xmlsec/xmlstreamio.cxx
@@ -33,8 +33,9 @@ static bool g_bInputCallbacksRegistered = false;
 
 static css::uno::Reference< css::xml::crypto::XUriBinding > m_xUriBinding ;
 
-extern "C"
-int xmlStreamMatch( const char* uri )
+extern "C" {
+
+static int xmlStreamMatch( const char* uri )
 {
     css::uno::Reference< css::io::XInputStream > xInputStream ;
 
@@ -65,8 +66,7 @@ int xmlStreamMatch( const char* uri )
         return 0 ;
 }
 
-extern "C"
-void* xmlStreamOpen( const char* uri )
+static void* xmlStreamOpen( const char* uri )
 {
     css::uno::Reference< css::io::XInputStream > xInputStream ;
 
@@ -99,8 +99,7 @@ void* xmlStreamOpen( const char* uri )
     return nullptr ;
 }
 
-extern "C"
-int xmlStreamRead( void* context, char* buffer, int len )
+static int xmlStreamRead( void* context, char* buffer, int len )
 {
     int numbers ;
     css::uno::Reference< css::io::XInputStream > xInputStream ;
@@ -124,8 +123,7 @@ int xmlStreamRead( void* context, char* buffer, int len )
     return numbers ;
 }
 
-extern "C"
-int xmlStreamClose( void * context )
+static int xmlStreamClose( void * context )
 {
     if (g_bInputCallbacksEnabled && g_bInputCallbacksRegistered)
     {
@@ -139,6 +137,8 @@ int xmlStreamClose( void * context )
     return 0 ;
 }
 
+}
+
 XSECXMLSEC_DLLPUBLIC int xmlEnableStreamInputCallbacks()
 {
     if (!g_bInputCallbacksEnabled)