Flag unreferrenced functions only declared in the main file, not an include

...which appears to be a good heuristic to identify functions that are either
unused or should better be declared just once in an include file.  (It also
filters out SAL_DLLPUBLIC extern "C" function definitions, which are most likely
meant to be referenced dynamically via dlsym.)

Change-Id: I7fb78cb836b971791704851535dcfbda2b2f5bc0

1 files changed, 24 insertions, 0 deletions

diff --git a/compilerplugins/clang/compat.hxx b/compilerplugins/clang/compat.hxx
index 3d265722c044..7389f636d0bf 100644
--- a/compilerplugins/clang/compat.hxx
+++ b/compilerplugins/clang/compat.hxx
@@ -20,7 +20,9 @@
 #include "clang/AST/Type.h"
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/DiagnosticIDs.h"
+#include "clang/Basic/Linkage.h"
 #include "clang/Basic/SourceManager.h"
+#include "clang/Basic/Visibility.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/raw_ostream.h"
@@ -52,6 +54,28 @@ inline bool isExternCContext(clang::DeclContext const & ctxt) {
 #endif
 }
 
+#if (__clang_major__ == 3 && __clang_minor__ >= 3) || __clang_major__ > 3
+typedef clang::LinkageInfo LinkageInfo;
+#else
+typedef clang::NamedDecl::LinkageInfo LinkageInfo;
+#endif
+
+inline clang::Linkage getLinkage(LinkageInfo const & info) {
+#if (__clang_major__ == 3 && __clang_minor__ >= 3) || __clang_major__ > 3
+    return info.getLinkage();
+#else
+    return info.linkage();
+#endif
+}
+
+inline clang::Visibility getVisibility(LinkageInfo const & info) {
+#if (__clang_major__ == 3 && __clang_minor__ >= 3) || __clang_major__ > 3
+    return info.getVisibility();
+#else
+    return info.visibility();
+#endif
+}
+
 inline bool isFirstDecl(clang::FunctionDecl const & decl) {
 #if (__clang_major__ == 3 && __clang_minor__ >= 4) || __clang_major__ > 3
     return decl.isFirstDecl();