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