compilerplugins/clang/store/revisibility.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #include "plugin.hxx"
  11
  12 // Find function declarations that redundantly re-specify a visibility attribute
  13 // (via SAL_DLLPUBLIC_EXPORT etc.) that was already specified with a previous
  14 // declaration of that function.  But MSVC wants consistency of __declspec
  15 // across friend declarations, so just ignore those for now.
  16
  17 namespace {
  18
  19 bool hasExplicitVisibilityAttr(Decl const * decl) {
  20     VisibilityAttr const * attr = decl->getAttr<VisibilityAttr>();
  21     return attr != nullptr && !attr->isInherited();
  22 }
  23
  24 bool isFriendDecl(Decl const * decl) {
  25     return decl->getFriendObjectKind() != Decl::FOK_None;
  26 }
  27
  28 class ReVisibility:
  29     public loplugin::FilteringPlugin<ReVisibility>
  30 {
  31 public:
  32     explicit ReVisibility(InstantiationData const & data): FilteringPlugin(data) {}
  33
  34     void run() override
  35     { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
  36
  37     bool VisitFunctionDecl(FunctionDecl const * decl);
  38 };
  39
  40 bool ReVisibility::VisitFunctionDecl(FunctionDecl const * decl) {
  41     if (!ignoreLocation(decl) && hasExplicitVisibilityAttr(decl)
  42         && !isFriendDecl(decl))
  43     {
  44         Decl const * first = nullptr;
  45         for (Decl const * p = decl;;) {
  46             p = p->getPreviousDecl();
  47             if (p == nullptr) {
  48                 break;
  49             }
  50             first = p;
  51             if (hasExplicitVisibilityAttr(p) && !isFriendDecl(p)) {
  52                 report(
  53                     DiagnosticsEngine::Warning,
  54                     "Redundant visibility re-declaration",
  55                     decl->getAttr<VisibilityAttr>()->getLocation())
  56                     << decl->getAttr<VisibilityAttr>()->getRange();
  57                 report(
  58                     DiagnosticsEngine::Note,
  59                     "Previous visibility declaration is here",
  60                     p->getAttr<VisibilityAttr>()->getLocation())
  61                     << p->getAttr<VisibilityAttr>()->getRange();
  62                 return true;
  63             }
  64         }
  65         if (decl->isThisDeclarationADefinition() && first != nullptr
  66             && !(getFilenameOfLocation(
  67                      compiler.getSourceManager().getSpellingLoc(
  68                          decl->getLocation()))
  69                  .startswith(SRCDIR "/libreofficekit/")))
  70         {
  71             report(
  72                 DiagnosticsEngine::Warning,
  73                 "Visibility declaration on definition, not first declaration",
  74                 decl->getAttr<VisibilityAttr>()->getLocation())
  75                 << decl->getAttr<VisibilityAttr>()->getRange();
  76             report(
  77                 DiagnosticsEngine::Note, "First declaration is here",
  78                 first->getLocation())
  79                 << first->getSourceRange();
  80         }
  81     }
  82     return true;
  83 }
  84
  85 loplugin::Plugin::Registration<ReVisibility> X("revisibility");
  86
  87 }
  88
  89 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */