Пример #1
0
void ThrUnsafeFCallChecker::checkASTDecl(const CXXMethodDecl *MD, AnalysisManager& mgr,
                    BugReporter &BR) const {
       	const SourceManager &SM = BR.getSourceManager();
       	PathDiagnosticLocation DLoc =PathDiagnosticLocation::createBegin( MD, SM );
	if ( SM.isInSystemHeader(DLoc.asLocation()) || SM.isInExternCSystemHeader(DLoc.asLocation()) ) return;
       	if (!MD->doesThisDeclarationHaveABody()) return;
	clangcms::TUFWalker walker(this,BR, mgr.getAnalysisDeclContext(MD));
	walker.Visit(MD->getBody());
       	return;
} 
Пример #2
0
std::shared_ptr<PathDiagnosticPiece>
SuperDeallocBRVisitor::VisitNode(const ExplodedNode *Succ,
                                 const ExplodedNode *Pred,
                                 BugReporterContext &BRC, BugReport &BR) {
  if (Satisfied)
    return nullptr;

  ProgramStateRef State = Succ->getState();

  bool CalledNow =
      Succ->getState()->contains<CalledSuperDealloc>(ReceiverSymbol);
  bool CalledBefore =
      Pred->getState()->contains<CalledSuperDealloc>(ReceiverSymbol);

  // Is Succ the node on which the analyzer noted that [super dealloc] was
  // called on ReceiverSymbol?
  if (CalledNow && !CalledBefore) {
    Satisfied = true;

    ProgramPoint P = Succ->getLocation();
    PathDiagnosticLocation L =
        PathDiagnosticLocation::create(P, BRC.getSourceManager());

    if (!L.isValid() || !L.asLocation().isValid())
      return nullptr;

    return std::make_shared<PathDiagnosticEventPiece>(
        L, "[super dealloc] called here");
  }

  return nullptr;
}
Пример #3
0
/// Add an extra note piece describing a declaration that is important
/// for understanding the bug report.
void ObjCDeallocChecker::addNoteForDecl(std::unique_ptr<BugReport> &BR,
                                             StringRef Msg,
                                             const Decl *D) const {
  ASTContext &ACtx = D->getASTContext();
  SourceManager &SM = ACtx.getSourceManager();
  PathDiagnosticLocation Pos = PathDiagnosticLocation::createBegin(D, SM);
  if (Pos.isValid() && Pos.asLocation().isValid())
    BR->addNote(Msg, Pos, D->getSourceRange());
}
Пример #4
0
std::shared_ptr<PathDiagnosticPiece>
GenericTaintChecker::TaintBugVisitor::VisitNode(const ExplodedNode *N,
    const ExplodedNode *PrevN, BugReporterContext &BRC, BugReport &BR) {

  // Find the ExplodedNode where the taint was first introduced
  if (!N->getState()->isTainted(V) || PrevN->getState()->isTainted(V))
    return nullptr;

  const Stmt *S = PathDiagnosticLocation::getStmt(N);
  if (!S)
    return nullptr;

  const LocationContext *NCtx = N->getLocationContext();
  PathDiagnosticLocation L =
      PathDiagnosticLocation::createBegin(S, BRC.getSourceManager(), NCtx);
  if (!L.isValid() || !L.asLocation().isValid())
    return nullptr;

  return std::make_shared<PathDiagnosticEventPiece>(
      L, "Taint originated here");
}
PathDiagnosticPiece *DivisionBRVisitor::VisitNode(const ExplodedNode *Succ,
                                                  const ExplodedNode *Pred,
                                                  BugReporterContext &BRC,
                                                  BugReport &BR) {
  if (Satisfied)
    return nullptr;

  const Expr *E = nullptr;

  if (Optional<PostStmt> P = Succ->getLocationAs<PostStmt>())
    if (const BinaryOperator *BO = P->getStmtAs<BinaryOperator>()) {
      BinaryOperator::Opcode Op = BO->getOpcode();
      if (Op == BO_Div || Op == BO_Rem || Op == BO_DivAssign ||
          Op == BO_RemAssign) {
        E = BO->getRHS();
      }
    }

  if (!E)
    return nullptr;

  ProgramStateRef State = Succ->getState();
  SVal S = State->getSVal(E, Succ->getLocationContext());
  if (ZeroSymbol == S.getAsSymbol() && SFC == Succ->getStackFrame()) {
    Satisfied = true;

    // Construct a new PathDiagnosticPiece.
    ProgramPoint P = Succ->getLocation();
    PathDiagnosticLocation L =
        PathDiagnosticLocation::create(P, BRC.getSourceManager());

    if (!L.isValid() || !L.asLocation().isValid())
      return nullptr;

    return new PathDiagnosticEventPiece(
        L, "Division with compared value made here");
  }

  return nullptr;
}
void PlistDiagnostics::FlushDiagnosticsImpl(
                                    std::vector<const PathDiagnostic *> &Diags,
                                    FilesMade *filesMade) {
  // Build up a set of FIDs that we use by scanning the locations and
  // ranges of the diagnostics.
  FIDMap FM;
  SmallVector<FileID, 10> Fids;
  const SourceManager* SM = nullptr;

  if (!Diags.empty())
    SM = &(*(*Diags.begin())->path.begin())->getLocation().getManager();


  for (std::vector<const PathDiagnostic*>::iterator DI = Diags.begin(),
       DE = Diags.end(); DI != DE; ++DI) {

    const PathDiagnostic *D = *DI;

    SmallVector<const PathPieces *, 5> WorkList;
    WorkList.push_back(&D->path);

    while (!WorkList.empty()) {
      const PathPieces &path = *WorkList.pop_back_val();

      for (PathPieces::const_iterator I = path.begin(), E = path.end(); I != E;
           ++I) {
        const PathDiagnosticPiece *piece = I->get();
        AddFID(FM, Fids, *SM, piece->getLocation().asLocation());
        ArrayRef<SourceRange> Ranges = piece->getRanges();
        for (ArrayRef<SourceRange>::iterator I = Ranges.begin(),
                                             E = Ranges.end(); I != E; ++I) {
          AddFID(FM, Fids, *SM, I->getBegin());
          AddFID(FM, Fids, *SM, I->getEnd());
        }

        if (const PathDiagnosticCallPiece *call =
            dyn_cast<PathDiagnosticCallPiece>(piece)) {
          IntrusiveRefCntPtr<PathDiagnosticEventPiece>
            callEnterWithin = call->getCallEnterWithinCallerEvent();
          if (callEnterWithin)
            AddFID(FM, Fids, *SM, callEnterWithin->getLocation().asLocation());

          WorkList.push_back(&call->path);
        }
        else if (const PathDiagnosticMacroPiece *macro =
                 dyn_cast<PathDiagnosticMacroPiece>(piece)) {
          WorkList.push_back(&macro->subPieces);
        }
      }
    }
  }

  // Open the file.
  std::error_code EC;
  llvm::raw_fd_ostream o(OutputFile, EC, llvm::sys::fs::F_Text);
  if (EC) {
    llvm::errs() << "warning: could not create file: " << EC.message() << '\n';
    return;
  }

  EmitPlistHeader(o);

  // Write the root object: a <dict> containing...
  //  - "clang_version", the string representation of clang version
  //  - "files", an <array> mapping from FIDs to file names
  //  - "diagnostics", an <array> containing the path diagnostics
  o << "<dict>\n" <<
       " <key>clang_version</key>\n";
  EmitString(o, getClangFullVersion()) << '\n';
  o << " <key>files</key>\n"
       " <array>\n";

  for (FileID FID : Fids)
    EmitString(o << "  ", SM->getFileEntryForID(FID)->getName()) << '\n';

  o << " </array>\n"
       " <key>diagnostics</key>\n"
       " <array>\n";

  for (std::vector<const PathDiagnostic*>::iterator DI=Diags.begin(),
       DE = Diags.end(); DI!=DE; ++DI) {

    o << "  <dict>\n"
         "   <key>path</key>\n";

    const PathDiagnostic *D = *DI;

    o << "   <array>\n";

    for (PathPieces::const_iterator I = D->path.begin(), E = D->path.end();
         I != E; ++I)
      ReportDiag(o, **I, FM, *SM, LangOpts);

    o << "   </array>\n";

    // Output the bug type and bug category.
    o << "   <key>description</key>";
    EmitString(o, D->getShortDescription()) << '\n';
    o << "   <key>category</key>";
    EmitString(o, D->getCategory()) << '\n';
    o << "   <key>type</key>";
    EmitString(o, D->getBugType()) << '\n';
    o << "   <key>check_name</key>";
    EmitString(o, D->getCheckName()) << '\n';

    o << "   <!-- This hash is experimental and going to change! -->\n";
    o << "   <key>issue_hash_content_of_line_in_context</key>";
    PathDiagnosticLocation UPDLoc = D->getUniqueingLoc();
    FullSourceLoc L(SM->getExpansionLoc(UPDLoc.isValid()
                                            ? UPDLoc.asLocation()
                                            : D->getLocation().asLocation()),
                    *SM);
    const Decl *DeclWithIssue = D->getDeclWithIssue();
    EmitString(o, GetIssueHash(*SM, L, D->getCheckName(), D->getBugType(),
                               DeclWithIssue))
        << '\n';

    // Output information about the semantic context where
    // the issue occurred.
    if (const Decl *DeclWithIssue = D->getDeclWithIssue()) {
      // FIXME: handle blocks, which have no name.
      if (const NamedDecl *ND = dyn_cast<NamedDecl>(DeclWithIssue)) {
        StringRef declKind;
        switch (ND->getKind()) {
          case Decl::CXXRecord:
            declKind = "C++ class";
            break;
          case Decl::CXXMethod:
            declKind = "C++ method";
            break;
          case Decl::ObjCMethod:
            declKind = "Objective-C method";
            break;
          case Decl::Function:
            declKind = "function";
            break;
          default:
            break;
        }
        if (!declKind.empty()) {
          const std::string &declName = ND->getDeclName().getAsString();
          o << "  <key>issue_context_kind</key>";
          EmitString(o, declKind) << '\n';
          o << "  <key>issue_context</key>";
          EmitString(o, declName) << '\n';
        }

        // Output the bug hash for issue unique-ing. Currently, it's just an
        // offset from the beginning of the function.
        if (const Stmt *Body = DeclWithIssue->getBody()) {

          // If the bug uniqueing location exists, use it for the hash.
          // For example, this ensures that two leaks reported on the same line
          // will have different issue_hashes and that the hash will identify
          // the leak location even after code is added between the allocation
          // site and the end of scope (leak report location).
          if (UPDLoc.isValid()) {
            FullSourceLoc UFunL(SM->getExpansionLoc(
              D->getUniqueingDecl()->getBody()->getLocStart()), *SM);
            o << "  <key>issue_hash_function_offset</key><string>"
              << L.getExpansionLineNumber() - UFunL.getExpansionLineNumber()
              << "</string>\n";

          // Otherwise, use the location on which the bug is reported.
          } else {
            FullSourceLoc FunL(SM->getExpansionLoc(Body->getLocStart()), *SM);
            o << "  <key>issue_hash_function_offset</key><string>"
              << L.getExpansionLineNumber() - FunL.getExpansionLineNumber()
              << "</string>\n";
          }

        }
      }
    }

    // Output the location of the bug.
    o << "  <key>location</key>\n";
    EmitLocation(o, *SM, D->getLocation().asLocation(), FM, 2);

    // Output the diagnostic to the sub-diagnostic client, if any.
    if (!filesMade->empty()) {
      StringRef lastName;
      PDFileEntry::ConsumerFiles *files = filesMade->getFiles(*D);
      if (files) {
        for (PDFileEntry::ConsumerFiles::const_iterator CI = files->begin(),
                CE = files->end(); CI != CE; ++CI) {
          StringRef newName = CI->first;
          if (newName != lastName) {
            if (!lastName.empty()) {
              o << "  </array>\n";
            }
            lastName = newName;
            o <<  "  <key>" << lastName << "_files</key>\n";
            o << "  <array>\n";
          }
          o << "   <string>" << CI->second << "</string>\n";
        }
        o << "  </array>\n";
      }
    }

    // Close up the entry.
    o << "  </dict>\n";
  }

  o << " </array>\n";

  // Finish.
  o << "</dict>\n</plist>";
}
Пример #7
0
PathDiagnosticLocation PathDiagnosticLocation::createSingleLocation(
                                           const PathDiagnosticLocation &PDL) {
  FullSourceLoc L = PDL.asLocation();
  return PathDiagnosticLocation(L, L.getManager(), SingleLocK);
}
void UnreachableCodeChecker::checkEndAnalysis(ExplodedGraph &G,
                                              BugReporter &B,
                                              ExprEngine &Eng) const {
  CFGBlocksSet reachable, visited;

  if (Eng.hasWorkRemaining())
    return;

  const Decl *D = nullptr;
  CFG *C = nullptr;
  ParentMap *PM = nullptr;
  const LocationContext *LC = nullptr;
  // Iterate over ExplodedGraph
  for (ExplodedGraph::node_iterator I = G.nodes_begin(), E = G.nodes_end();
      I != E; ++I) {
    const ProgramPoint &P = I->getLocation();
    LC = P.getLocationContext();
    if (!LC->inTopFrame())
      continue;

    if (!D)
      D = LC->getAnalysisDeclContext()->getDecl();

    // Save the CFG if we don't have it already
    if (!C)
      C = LC->getAnalysisDeclContext()->getUnoptimizedCFG();
    if (!PM)
      PM = &LC->getParentMap();

    if (Optional<BlockEntrance> BE = P.getAs<BlockEntrance>()) {
      const CFGBlock *CB = BE->getBlock();
      reachable.insert(CB->getBlockID());
    }
  }

  // Bail out if we didn't get the CFG or the ParentMap.
  if (!D || !C || !PM)
    return;

  // Don't do anything for template instantiations.  Proving that code
  // in a template instantiation is unreachable means proving that it is
  // unreachable in all instantiations.
  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
    if (FD->isTemplateInstantiation())
      return;

  // Find CFGBlocks that were not covered by any node
  for (CFG::const_iterator I = C->begin(), E = C->end(); I != E; ++I) {
    const CFGBlock *CB = *I;
    // Check if the block is unreachable
    if (reachable.count(CB->getBlockID()))
      continue;

    // Check if the block is empty (an artificial block)
    if (isEmptyCFGBlock(CB))
      continue;

    // Find the entry points for this block
    if (!visited.count(CB->getBlockID()))
      FindUnreachableEntryPoints(CB, reachable, visited);

    // This block may have been pruned; check if we still want to report it
    if (reachable.count(CB->getBlockID()))
      continue;

    // Check for false positives
    if (isInvalidPath(CB, *PM))
      continue;

    // It is good practice to always have a "default" label in a "switch", even
    // if we should never get there. It can be used to detect errors, for
    // instance. Unreachable code directly under a "default" label is therefore
    // likely to be a false positive.
    if (const Stmt *label = CB->getLabel())
      if (label->getStmtClass() == Stmt::DefaultStmtClass)
        continue;

    // Special case for __builtin_unreachable.
    // FIXME: This should be extended to include other unreachable markers,
    // such as llvm_unreachable.
    if (!CB->empty()) {
      bool foundUnreachable = false;
      for (CFGBlock::const_iterator ci = CB->begin(), ce = CB->end();
           ci != ce; ++ci) {
        if (Optional<CFGStmt> S = (*ci).getAs<CFGStmt>())
          if (const CallExpr *CE = dyn_cast<CallExpr>(S->getStmt())) {
            if (CE->getBuiltinCallee() == Builtin::BI__builtin_unreachable ||
                CE->isBuiltinAssumeFalse(Eng.getContext())) {
              foundUnreachable = true;
              break;
            }
          }
      }
      if (foundUnreachable)
        continue;
    }

    // We found a block that wasn't covered - find the statement to report
    SourceRange SR;
    PathDiagnosticLocation DL;
    SourceLocation SL;
    if (const Stmt *S = getUnreachableStmt(CB)) {
      // In macros, 'do {...} while (0)' is often used. Don't warn about the
      // condition 0 when it is unreachable.
      if (S->getBeginLoc().isMacroID())
        if (const auto *I = dyn_cast<IntegerLiteral>(S))
          if (I->getValue() == 0ULL)
            if (const Stmt *Parent = PM->getParent(S))
              if (isa<DoStmt>(Parent))
                continue;
      SR = S->getSourceRange();
      DL = PathDiagnosticLocation::createBegin(S, B.getSourceManager(), LC);
      SL = DL.asLocation();
      if (SR.isInvalid() || !SL.isValid())
        continue;
    }
    else
      continue;

    // Check if the SourceLocation is in a system header
    const SourceManager &SM = B.getSourceManager();
    if (SM.isInSystemHeader(SL) || SM.isInExternCSystemHeader(SL))
      continue;

    B.EmitBasicReport(D, this, "Unreachable code", "Dead code",
                      "This statement is never executed", DL, SR);
  }
}
Пример #9
0
static void EmitLocation(raw_ostream &o, const SourceManager &SM,
                         const LangOptions &LangOpts,
                         const PathDiagnosticLocation &L, const FIDMap& FM,
                         unsigned indent, bool extend = false) {
  EmitLocation(o, SM, LangOpts, L.asLocation(), FM, indent, extend);
}
Пример #10
0
void HTMLDiagnostics::ReportDiag(const PathDiagnostic& D,
                                 FilesMade *filesMade) {

  // Create the HTML directory if it is missing.
  if (!createdDir) {
    createdDir = true;
    if (std::error_code ec = llvm::sys::fs::create_directories(Directory)) {
      llvm::errs() << "warning: could not create directory '"
                   << Directory << "': " << ec.message() << '\n';

      noDir = true;

      return;
    }
  }

  if (noDir)
    return;

  // First flatten out the entire path to make it easier to use.
  PathPieces path = D.path.flatten(/*ShouldFlattenMacros=*/false);

  // The path as already been prechecked that all parts of the path are
  // from the same file and that it is non-empty.
  const SourceManager &SMgr = path.front()->getLocation().getManager();
  assert(!path.empty());
  FileID FID =
    path.front()->getLocation().asLocation().getExpansionLoc().getFileID();
  assert(FID.isValid());

  // Create a new rewriter to generate HTML.
  Rewriter R(const_cast<SourceManager&>(SMgr), PP.getLangOpts());

  // Get the function/method name
  SmallString<128> declName("unknown");
  int offsetDecl = 0;
  if (const Decl *DeclWithIssue = D.getDeclWithIssue()) {
      if (const NamedDecl *ND = dyn_cast<NamedDecl>(DeclWithIssue)) {
          declName = ND->getDeclName().getAsString();
      }

      if (const Stmt *Body = DeclWithIssue->getBody()) {
          // Retrieve the relative position of the declaration which will be used
          // for the file name
          FullSourceLoc L(
              SMgr.getExpansionLoc(path.back()->getLocation().asLocation()),
              SMgr);
          FullSourceLoc FunL(SMgr.getExpansionLoc(Body->getLocStart()), SMgr);
          offsetDecl = L.getExpansionLineNumber() - FunL.getExpansionLineNumber();
      }
  }

  // Process the path.
  // Maintain the counts of extra note pieces separately.
  unsigned TotalPieces = path.size();
  unsigned TotalNotePieces =
      std::count_if(path.begin(), path.end(),
                    [](const std::shared_ptr<PathDiagnosticPiece> &p) {
                      return isa<PathDiagnosticNotePiece>(*p);
                    });

  unsigned TotalRegularPieces = TotalPieces - TotalNotePieces;
  unsigned NumRegularPieces = TotalRegularPieces;
  unsigned NumNotePieces = TotalNotePieces;

  for (auto I = path.rbegin(), E = path.rend(); I != E; ++I) {
    if (isa<PathDiagnosticNotePiece>(I->get())) {
      // This adds diagnostic bubbles, but not navigation.
      // Navigation through note pieces would be added later,
      // as a separate pass through the piece list.
      HandlePiece(R, FID, **I, NumNotePieces, TotalNotePieces);
      --NumNotePieces;
    } else {
      HandlePiece(R, FID, **I, NumRegularPieces, TotalRegularPieces);
      --NumRegularPieces;
    }
  }

  // Add line numbers, header, footer, etc.

  // unsigned FID = R.getSourceMgr().getMainFileID();
  html::EscapeText(R, FID);
  html::AddLineNumbers(R, FID);

  // If we have a preprocessor, relex the file and syntax highlight.
  // We might not have a preprocessor if we come from a deserialized AST file,
  // for example.

  html::SyntaxHighlight(R, FID, PP);
  html::HighlightMacros(R, FID, PP);

  // Get the full directory name of the analyzed file.

  const FileEntry* Entry = SMgr.getFileEntryForID(FID);

  // This is a cludge; basically we want to append either the full
  // working directory if we have no directory information.  This is
  // a work in progress.

  llvm::SmallString<0> DirName;

  if (llvm::sys::path::is_relative(Entry->getName())) {
    llvm::sys::fs::current_path(DirName);
    DirName += '/';
  }

  int LineNumber = path.back()->getLocation().asLocation().getExpansionLineNumber();
  int ColumnNumber = path.back()->getLocation().asLocation().getExpansionColumnNumber();

  // Add the name of the file as an <h1> tag.
  {
    std::string s;
    llvm::raw_string_ostream os(s);

    os << "<!-- REPORTHEADER -->\n"
       << "<h3>Bug Summary</h3>\n<table class=\"simpletable\">\n"
          "<tr><td class=\"rowname\">File:</td><td>"
       << html::EscapeText(DirName)
       << html::EscapeText(Entry->getName())
       << "</td></tr>\n<tr><td class=\"rowname\">Warning:</td><td>"
          "<a href=\"#EndPath\">line "
       << LineNumber
       << ", column "
       << ColumnNumber
       << "</a><br />"
       << D.getVerboseDescription() << "</td></tr>\n";

    // The navigation across the extra notes pieces.
    unsigned NumExtraPieces = 0;
    for (const auto &Piece : path) {
      if (const auto *P = dyn_cast<PathDiagnosticNotePiece>(Piece.get())) {
        int LineNumber =
            P->getLocation().asLocation().getExpansionLineNumber();
        int ColumnNumber =
            P->getLocation().asLocation().getExpansionColumnNumber();
        os << "<tr><td class=\"rowname\">Note:</td><td>"
           << "<a href=\"#Note" << NumExtraPieces << "\">line "
           << LineNumber << ", column " << ColumnNumber << "</a><br />"
           << P->getString() << "</td></tr>";
        ++NumExtraPieces;
      }
    }

    // Output any other meta data.

    for (PathDiagnostic::meta_iterator I=D.meta_begin(), E=D.meta_end();
         I!=E; ++I) {
      os << "<tr><td></td><td>" << html::EscapeText(*I) << "</td></tr>\n";
    }

    os << "</table>\n<!-- REPORTSUMMARYEXTRA -->\n"
          "<h3>Annotated Source Code</h3>\n";

    R.InsertTextBefore(SMgr.getLocForStartOfFile(FID), os.str());
  }

  // Embed meta-data tags.
  {
    std::string s;
    llvm::raw_string_ostream os(s);

    StringRef BugDesc = D.getVerboseDescription();
    if (!BugDesc.empty())
      os << "\n<!-- BUGDESC " << BugDesc << " -->\n";

    StringRef BugType = D.getBugType();
    if (!BugType.empty())
      os << "\n<!-- BUGTYPE " << BugType << " -->\n";

    PathDiagnosticLocation UPDLoc = D.getUniqueingLoc();
    FullSourceLoc L(SMgr.getExpansionLoc(UPDLoc.isValid()
                                             ? UPDLoc.asLocation()
                                             : D.getLocation().asLocation()),
                    SMgr);
    const Decl *DeclWithIssue = D.getDeclWithIssue();

    StringRef BugCategory = D.getCategory();
    if (!BugCategory.empty())
      os << "\n<!-- BUGCATEGORY " << BugCategory << " -->\n";

    os << "\n<!-- BUGFILE " << DirName << Entry->getName() << " -->\n";

    os << "\n<!-- FILENAME " << llvm::sys::path::filename(Entry->getName()) << " -->\n";

    os  << "\n<!-- FUNCTIONNAME " <<  declName << " -->\n";

    os << "\n<!-- ISSUEHASHCONTENTOFLINEINCONTEXT "
       << GetIssueHash(SMgr, L, D.getCheckName(), D.getBugType(), DeclWithIssue,
                       PP.getLangOpts()) << " -->\n";

    os << "\n<!-- BUGLINE "
       << LineNumber
       << " -->\n";

    os << "\n<!-- BUGCOLUMN "
      << ColumnNumber
      << " -->\n";

    os << "\n<!-- BUGPATHLENGTH " << path.size() << " -->\n";

    // Mark the end of the tags.
    os << "\n<!-- BUGMETAEND -->\n";

    // Insert the text.
    R.InsertTextBefore(SMgr.getLocForStartOfFile(FID), os.str());
  }

  // Add CSS, header, and footer.

  html::AddHeaderFooterInternalBuiltinCSS(R, FID, Entry->getName());

  // Get the rewrite buffer.
  const RewriteBuffer *Buf = R.getRewriteBufferFor(FID);

  if (!Buf) {
    llvm::errs() << "warning: no diagnostics generated for main file.\n";
    return;
  }

  // Create a path for the target HTML file.
  int FD;
  SmallString<128> Model, ResultPath;

  if (!AnalyzerOpts.shouldWriteStableReportFilename()) {
      llvm::sys::path::append(Model, Directory, "report-%%%%%%.html");
      if (std::error_code EC =
          llvm::sys::fs::make_absolute(Model)) {
          llvm::errs() << "warning: could not make '" << Model
                       << "' absolute: " << EC.message() << '\n';
        return;
      }
      if (std::error_code EC =
          llvm::sys::fs::createUniqueFile(Model, FD, ResultPath)) {
          llvm::errs() << "warning: could not create file in '" << Directory
                       << "': " << EC.message() << '\n';
          return;
      }

  } else {
      int i = 1;
      std::error_code EC;
      do {
          // Find a filename which is not already used
          std::stringstream filename;
          Model = "";
          filename << "report-"
                   << llvm::sys::path::filename(Entry->getName()).str()
                   << "-" << declName.c_str()
                   << "-" << offsetDecl
                   << "-" << i << ".html";
          llvm::sys::path::append(Model, Directory,
                                  filename.str());
          EC = llvm::sys::fs::openFileForWrite(Model,
                                               FD,
                                               llvm::sys::fs::F_RW |
                                               llvm::sys::fs::F_Excl);
          if (EC && EC != llvm::errc::file_exists) {
              llvm::errs() << "warning: could not create file '" << Model
                           << "': " << EC.message() << '\n';
              return;
          }
          i++;
      } while (EC);
  }

  llvm::raw_fd_ostream os(FD, true);

  if (filesMade)
    filesMade->addDiagnostic(D, getName(),
                             llvm::sys::path::filename(ResultPath));

  // Emit the HTML to disk.
  for (RewriteBuffer::iterator I = Buf->begin(), E = Buf->end(); I!=E; ++I)
      os << *I;
}
void UnreachableCodeChecker::checkEndAnalysis(ExplodedGraph &G,
                                              BugReporter &B,
                                              ExprEngine &Eng) const {
  CFGBlocksSet reachable, visited;

  if (Eng.hasWorkRemaining())
    return;

  CFG *C = 0;
  ParentMap *PM = 0;
  const LocationContext *LC = 0;
  // Iterate over ExplodedGraph
  for (ExplodedGraph::node_iterator I = G.nodes_begin(), E = G.nodes_end();
      I != E; ++I) {
    const ProgramPoint &P = I->getLocation();
    LC = P.getLocationContext();

    // Save the CFG if we don't have it already
    if (!C)
      C = LC->getAnalysisContext()->getUnoptimizedCFG();
    if (!PM)
      PM = &LC->getParentMap();

    if (const BlockEntrance *BE = dyn_cast<BlockEntrance>(&P)) {
      const CFGBlock *CB = BE->getBlock();
      reachable.insert(CB->getBlockID());
    }
  }

  // Bail out if we didn't get the CFG or the ParentMap.
  if (!C || !PM)
    return;

  ASTContext &Ctx = B.getContext();

  // Find CFGBlocks that were not covered by any node
  for (CFG::const_iterator I = C->begin(), E = C->end(); I != E; ++I) {
    const CFGBlock *CB = *I;
    // Check if the block is unreachable
    if (reachable.count(CB->getBlockID()))
      continue;

    // Check if the block is empty (an artificial block)
    if (isEmptyCFGBlock(CB))
      continue;

    // Find the entry points for this block
    if (!visited.count(CB->getBlockID()))
      FindUnreachableEntryPoints(CB, reachable, visited);

    // This block may have been pruned; check if we still want to report it
    if (reachable.count(CB->getBlockID()))
      continue;

    // Check for false positives
    if (CB->size() > 0 && isInvalidPath(CB, *PM))
      continue;

    // Special case for __builtin_unreachable.
    // FIXME: This should be extended to include other unreachable markers,
    // such as llvm_unreachable.
    if (!CB->empty()) {
      bool foundUnreachable = false;
      for (CFGBlock::const_iterator ci = CB->begin(), ce = CB->end();
           ci != ce; ++ci) {
        if (const CFGStmt *S = (*ci).getAs<CFGStmt>())
          if (const CallExpr *CE = dyn_cast<CallExpr>(S->getStmt())) {
            if (CE->isBuiltinCall(Ctx) == Builtin::BI__builtin_unreachable) {
              foundUnreachable = true;
              break;
            }
          }
      }
      if (foundUnreachable)
        continue;
    }

    // We found a block that wasn't covered - find the statement to report
    SourceRange SR;
    PathDiagnosticLocation DL;
    SourceLocation SL;
    if (const Stmt *S = getUnreachableStmt(CB)) {
      SR = S->getSourceRange();
      DL = PathDiagnosticLocation::createBegin(S, B.getSourceManager(), LC);
      SL = DL.asLocation();
      if (SR.isInvalid() || !SL.isValid())
        continue;
    }
    else
      continue;

    // Check if the SourceLocation is in a system header
    const SourceManager &SM = B.getSourceManager();
    if (SM.isInSystemHeader(SL) || SM.isInExternCSystemHeader(SL))
      continue;

    B.EmitBasicReport("Unreachable code", "Dead code", "This statement is never"
        " executed", DL, SR);
  }
}