clang/lib/StaticAnalyzer/Checkers/NSAutoreleasePoolChecker.cpp

   1 //=- NSAutoreleasePoolChecker.cpp --------------------------------*- C++ -*-==//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 //  This file defines a NSAutoreleasePoolChecker, a small checker that warns
  10 //  about subpar uses of NSAutoreleasePool.  Note that while the check itself
  11 //  (in its current form) could be written as a flow-insensitive check, in
  12 //  can be potentially enhanced in the future with flow-sensitive information.
  13 //  It is also a good example of the CheckerVisitor interface.
  14 //
  15 //===----------------------------------------------------------------------===//
  16
  17 #include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
  18 #include "clang/AST/Decl.h"
  19 #include "clang/AST/DeclObjC.h"
  20 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
  21 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
  22 #include "clang/StaticAnalyzer/Core/Checker.h"
  23 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
  24 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
  25 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
  26 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
  27
  28 using namespace clang;
  29 using namespace ento;
  30
  31 namespace {
  32 class NSAutoreleasePoolChecker
  33   : public Checker<check::PreObjCMessage> {
  34   mutable std::unique_ptr<BugType> BT;
  35   mutable Selector releaseS;
  36
  37 public:
  38   void checkPreObjCMessage(const ObjCMethodCall &msg, CheckerContext &C) const;
  39 };
  40
  41 } // end anonymous namespace
  42
  43 void NSAutoreleasePoolChecker::checkPreObjCMessage(const ObjCMethodCall &msg,
  44                                                    CheckerContext &C) const {
  45   if (!msg.isInstanceMessage())
  46     return;
  47
  48   const ObjCInterfaceDecl *OD = msg.getReceiverInterface();
  49   if (!OD)
  50     return;
  51   if (!OD->getIdentifier()->isStr("NSAutoreleasePool"))
  52     return;
  53
  54   if (releaseS.isNull())
  55     releaseS = GetNullarySelector("release", C.getASTContext());
  56   // Sending 'release' message?
  57   if (msg.getSelector() != releaseS)
  58     return;
  59
  60   if (!BT)
  61     BT.reset(new BugType(this, "Use -drain instead of -release",
  62                          "API Upgrade (Apple)"));
  63
  64   ExplodedNode *N = C.generateNonFatalErrorNode();
  65   if (!N) {
  66     assert(0);
  67     return;
  68   }
  69
  70   auto Report = std::make_unique<PathSensitiveBugReport>(
  71       *BT,
  72       "Use -drain instead of -release when using NSAutoreleasePool and "
  73       "garbage collection",
  74       N);
  75   Report->addRange(msg.getSourceRange());
  76   C.emitReport(std::move(Report));
  77 }
  78
  79 void ento::registerNSAutoreleasePoolChecker(CheckerManager &mgr) {
  80   mgr.registerChecker<NSAutoreleasePoolChecker>();
  81 }
  82
  83 bool ento::shouldRegisterNSAutoreleasePoolChecker(const CheckerManager &mgr) {
  84   const LangOptions &LO = mgr.getLangOpts();
  85   return LO.getGC() != LangOptions::NonGC;
  86 }