compilerplugins/clang/nestedunnamed.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
   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 <cassert>
  11
  12 #include "plugin.hxx"
  13
  14 // Warn about unnamed namespaces nested (directly) within unnamed namespaces.  (It can be hard to
  15 // keep track whether a certain spot in a source file is already in an unnamed namespace, so it
  16 // happens that additions to the source add redundant, nested unnamed namespaces.)
  17
  18 namespace
  19 {
  20 class NestedUnnamed : public RecursiveASTVisitor<NestedUnnamed>, public loplugin::Plugin
  21 {
  22 public:
  23     explicit NestedUnnamed(loplugin::InstantiationData const& data)
  24         : Plugin(data)
  25     {
  26     }
  27
  28     void run() override
  29     {
  30         if (compiler.getLangOpts().CPlusPlus)
  31         {
  32             TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
  33         }
  34     }
  35
  36     bool VisitNamespaceDecl(NamespaceDecl const* decl)
  37     {
  38         if (ignoreLocation(decl))
  39         {
  40             return true;
  41         }
  42         if (!decl->isAnonymousNamespace())
  43         {
  44             return true;
  45         }
  46         NamespaceDecl const* outer;
  47         for (auto p = decl->getLexicalParent();; p = p->getLexicalParent())
  48         {
  49             outer = dyn_cast<NamespaceDecl>(p);
  50             if (outer != nullptr)
  51             {
  52                 break;
  53             }
  54             if (isa<TranslationUnitDecl>(p))
  55             {
  56                 return true;
  57             }
  58         }
  59         if (!outer->isAnonymousNamespace())
  60         {
  61             return true;
  62         }
  63         report(DiagnosticsEngine::Warning, "unnamed namespace directly nested in unnamed namespace",
  64                decl->getLocation())
  65             << decl->getSourceRange();
  66         report(DiagnosticsEngine::Note, "outer namespace declared here", outer->getLocation())
  67             << outer->getSourceRange();
  68         return true;
  69     }
  70 };
  71
  72 loplugin::Plugin::Registration<NestedUnnamed> X("nestedunnamed");
  73 }
  74
  75 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */