compilerplugins/clang/externandnotdefined.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 #ifndef LO_CLANG_SHARED_PLUGINS
  11
  12 #include <string>
  13
  14 #include "plugin.hxx"
  15
  16 // Having an extern prototype for a method in a module and not actually declaring that method is dodgy.
  17 //
  18
  19 namespace {
  20
  21 class ExternAndNotDefined:
  22     public loplugin::FilteringPlugin<ExternAndNotDefined>
  23 {
  24 public:
  25     explicit ExternAndNotDefined(loplugin::InstantiationData const & data): FilteringPlugin(data) {}
  26
  27     virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
  28
  29     bool VisitFunctionDecl(const FunctionDecl * decl);
  30 };
  31
  32 bool ExternAndNotDefined::VisitFunctionDecl(const FunctionDecl * functionDecl) {
  33     if (ignoreLocation(functionDecl)) {
  34         return true;
  35     }
  36     if (functionDecl->isDefined() || functionDecl->isPure()
  37       || (functionDecl->getLinkageAndVisibility().getLinkage()
  38           != ExternalLinkage)) {
  39         return true;
  40     }
  41     //TODO, filtering out anything template for now:
  42     if (functionDecl->isDependentContext()) {
  43         return true;
  44     }
  45     CXXRecordDecl const * r = dyn_cast<CXXRecordDecl>(functionDecl->getDeclContext());
  46     if (r != nullptr && r->getTemplateSpecializationKind() != TSK_Undeclared) {
  47         return true;
  48     }
  49     // this is the bison/flex C API, it has to be defined this way
  50     std::string functionName = functionDecl->getNameAsString();
  51     if (functionName == "yyerror" || functionName == "yyparse" || functionName == "yylex") {
  52         return true;
  53     }
  54     // see vcl/unx/gtk/app/gtksys.cxx, typename conflicts prevent using the right include
  55     if (functionName == "gdk_x11_screen_get_screen_number") {
  56         return true;
  57     }
  58     if (!compiler.getSourceManager().isInMainFile(functionDecl->getLocation()))
  59     {
  60         return true;
  61     }
  62     report(
  63         DiagnosticsEngine::Warning,
  64         "extern prototype in main file without definition",
  65         functionDecl->getLocation())
  66       << functionDecl->getSourceRange();
  67     return true;
  68 }
  69
  70
  71 loplugin::Plugin::Registration< ExternAndNotDefined > externandnotdefined("externandnotdefined");
  72
  73 }
  74
  75 #endif // LO_CLANG_SHARED_PLUGINS
  76
  77 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */