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/bridges/source/cpp_uno/gcc3_linux_x86-64/cpp2uno.cxx b/bridges/source/cpp_uno/gcc3_linux_x86-64/cpp2uno.cxx
index 12148904f9fd..6e860ea257ac 100644
--- a/bridges/source/cpp_uno/gcc3_linux_x86-64/cpp2uno.cxx
+++ b/bridges/source/cpp_uno/gcc3_linux_x86-64/cpp2uno.cxx
@@ -400,7 +400,7 @@ const int codeSnippetSize = 24;
 // Note: The code snippet we build here must not create a stack frame,
 // otherwise the UNO exceptions stop working thanks to non-existing
 // unwinding info.
-unsigned char * codeSnippet( unsigned char * code,
+static unsigned char * codeSnippet( unsigned char * code,
         sal_Int32 nFunctionIndex, sal_Int32 nVtableOffset,
         bool bHasHiddenParam )
 {
diff --git a/bridges/source/jni_uno/jni_bridge.cxx b/bridges/source/jni_uno/jni_bridge.cxx
index 7f38d3221420..6ff327a1eb06 100644
--- a/bridges/source/jni_uno/jni_bridge.cxx
+++ b/bridges/source/jni_uno/jni_bridge.cxx
@@ -422,7 +422,7 @@ using namespace ::jni_uno;
 
 extern "C" {
 
-void java_env_dispose(uno_Environment * env) {
+static void java_env_dispose(uno_Environment * env) {
     auto * envData
         = static_cast<jni_uno::JniUnoEnvironmentData *>(env->pContext);
     if (envData != nullptr) {
@@ -456,7 +456,7 @@ void java_env_dispose(uno_Environment * env) {
     }
 }
 
-void java_env_disposing(uno_Environment * env) {
+static void java_env_disposing(uno_Environment * env) {
     java_env_dispose(env);
     delete static_cast<jni_uno::JniUnoEnvironmentData *>(env->pContext);
 }
diff --git a/bridges/source/jni_uno/jni_data.cxx b/bridges/source/jni_uno/jni_data.cxx
index ac86fd391e4f..ebe2ce48cc1d 100644
--- a/bridges/source/jni_uno/jni_data.cxx
+++ b/bridges/source/jni_uno/jni_data.cxx
@@ -31,7 +31,7 @@ namespace jni_uno
 {
 
 
-inline std::unique_ptr<rtl_mem> seq_allocate(
+static inline std::unique_ptr<rtl_mem> seq_allocate(
     sal_Int32 nElements, sal_Int32 nSize )
 {
     std::unique_ptr< rtl_mem > seq(