From e1ab04440195092aa0bfbf445e97530082843569 Mon Sep 17 00:00:00 2001
From: Stephan Bergmann <sbergman@redhat.com>
Date: Fri, 1 Jun 2018 16:22:53 +0200
Subject: Improve loplugin:unreffun

...to avoid a false positive in --enable-qt5

> [build CXX] vcl/qt5/Qt5Widget.cxx
> /home/sbergman/lo/core/vcl/qt5/Qt5Widget.cxx:466:21: error: Unreferenced function declaration [loplugin:unreffun]
>     friend QWidget* createQt5Widget(Qt5Frame& rFrame, QWidget* parent, Qt::WindowFlags f);
>     ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 1 error generated.

Change-Id: I01e47bc5f5147916737d62fe18ce5312a0221a3f
Reviewed-on: https://gerrit.libreoffice.org/55189
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
---
 compilerplugins/clang/unreffun.cxx | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

(limited to 'compilerplugins/clang/unreffun.cxx')

diff --git a/compilerplugins/clang/unreffun.cxx b/compilerplugins/clang/unreffun.cxx
index d825423bfeaa..bfd48b328300 100644
--- a/compilerplugins/clang/unreffun.cxx
+++ b/compilerplugins/clang/unreffun.cxx
@@ -58,7 +58,18 @@ public:
     void run() override
     { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
 
+    bool TraverseFriendDecl(FriendDecl * decl) {
+        auto const old = friendFunction_;
+        friendFunction_ = dyn_cast_or_null<FunctionDecl>(decl->getFriendDecl());
+        auto const ret = RecursiveASTVisitor::TraverseFriendDecl(decl);
+        friendFunction_ = old;
+        return ret;
+    }
+
     bool VisitFunctionDecl(FunctionDecl const * decl);
+
+private:
+    FunctionDecl const * friendFunction_ = nullptr;
 };
 
 bool UnrefFun::VisitFunctionDecl(FunctionDecl const * decl) {
@@ -74,6 +85,13 @@ bool UnrefFun::VisitFunctionDecl(FunctionDecl const * decl) {
     {
         return true;
     }
+    if (decl == friendFunction_) {
+        if (auto const lex = dyn_cast<CXXRecordDecl>(decl->getLexicalDeclContext())) {
+            if (lex->isDependentContext()) {
+                return true;
+            }
+        }
+    }
 
     if (!(decl->isThisDeclarationADefinition() || isFriendDecl(decl)
           || decl->isFunctionTemplateSpecialization()))
-- 
cgit