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