//===- DiagnosticRenderer.cpp - Diagnostic Pretty-Printing ----------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#include "clang/Frontend/DiagnosticRenderer.h"

#include "clang/Basic/Diagnostic.h"

#include "clang/Basic/DiagnosticOptions.h"

#include "clang/Basic/LLVM.h"

#include "clang/Basic/SourceLocation.h"

#include "clang/Basic/SourceManager.h"

#include "clang/Edit/Commit.h"

#include "clang/Edit/EditedSource.h"

#include "clang/Edit/EditsReceiver.h"

#include "clang/Lex/Lexer.h"

#include "llvm/ADT/ArrayRef.h"

#include "llvm/ADT/DenseMap.h"

#include "llvm/ADT/SmallString.h"

#include "llvm/ADT/SmallVector.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/Support/raw_ostream.h"

#include <algorithm>

#include <cassert>

#include <iterator>

#include <utility>

using namespace clang;

DiagnosticRenderer::DiagnosticRenderer(const LangOptions &LangOpts,

                                       DiagnosticOptions *DiagOpts)

    : LangOpts(LangOpts), DiagOpts(DiagOpts), LastLevel() {}

DiagnosticRenderer::~DiagnosticRenderer() = default;

namespace {

class FixitReceiver : public edit::EditsReceiver {

  SmallVectorImpl<FixItHint> &MergedFixits;

public:

  FixitReceiver(SmallVectorImpl<FixItHint> &MergedFixits)

      : MergedFixits(MergedFixits) {}

  void insert(SourceLocation loc, StringRef text) override {

    MergedFixits.push_back(FixItHint::CreateInsertion(loc, text));

  }

  void replace(CharSourceRange range, StringRef text) override {

    MergedFixits.push_back(FixItHint::CreateReplacement(range, text));

  }

};

} // namespace

static void mergeFixits(ArrayRef<FixItHint> FixItHints,

                        const SourceManager &SM, const LangOptions &LangOpts,

                        SmallVectorImpl<FixItHint> &MergedFixits) {

  edit::Commit commit(SM, LangOpts);

  for (const auto &Hint : FixItHints)

    if (Hint.CodeToInsert.empty()) {

      if (Hint.InsertFromRange.isValid())

        commit.insertFromRange(Hint.RemoveRange.getBegin(),

                           Hint.InsertFromRange, /*afterToken=*/false,

                           Hint.BeforePreviousInsertions);

      else

        commit.remove(Hint.RemoveRange);

    } else {

      if (Hint.RemoveRange.isTokenRange() ||

          Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())

        commit.replace(Hint.RemoveRange, Hint.CodeToInsert);

      else

        commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,

                    /*afterToken=*/false, Hint.BeforePreviousInsertions);

    }

  edit::EditedSource Editor(SM, LangOpts);

  if (Editor.commit(commit)) {

    FixitReceiver Rec(MergedFixits);

    Editor.applyRewrites(Rec);

  }

}

void DiagnosticRenderer::emitDiagnostic(FullSourceLoc Loc,

                                        DiagnosticsEngine::Level Level,

                                        StringRef Message,

                                        ArrayRef<CharSourceRange> Ranges,

                                        ArrayRef<FixItHint> FixItHints,

                                        DiagOrStoredDiag D) {

  assert(Loc.hasManager() || Loc.isInvalid());

  beginDiagnostic(D, Level);

  if (!Loc.isValid())

    // If we have no source location, just emit the diagnostic message.

    emitDiagnosticMessage(Loc, PresumedLoc(), Level, Message, Ranges, D);

  else {

    // Get the ranges into a local array we can hack on.

    SmallVector<CharSourceRange, 20> MutableRanges(Ranges.begin(),

                                                   Ranges.end());

    SmallVector<FixItHint, 8> MergedFixits;

    if (!FixItHints.empty()) {

      mergeFixits(FixItHints, Loc.getManager(), LangOpts, MergedFixits);

      FixItHints = MergedFixits;

    }

    for (const auto &Hint : FixItHints)

      if (Hint.RemoveRange.isValid())

        MutableRanges.push_back(Hint.RemoveRange);

    FullSourceLoc UnexpandedLoc = Loc;

    // Find the ultimate expansion location for the diagnostic.

    Loc = Loc.getFileLoc();

    PresumedLoc PLoc = Loc.getPresumedLoc(DiagOpts->ShowPresumedLoc);

    // First, if this diagnostic is not in the main file, print out the

    // "included from" lines.

    emitIncludeStack(Loc, PLoc, Level);

    // Next, emit the actual diagnostic message and caret.

    emitDiagnosticMessage(Loc, PLoc, Level, Message, Ranges, D);

    emitCaret(Loc, Level, MutableRanges, FixItHints);

    // If this location is within a macro, walk from UnexpandedLoc up to Loc

    // and produce a macro backtrace.

    if (UnexpandedLoc.isValid() && UnexpandedLoc.isMacroID()) {

      emitMacroExpansions(UnexpandedLoc, Level, MutableRanges, FixItHints);

    }

  }

  LastLoc = Loc;

  LastLevel = Level;

  endDiagnostic(D, Level);

}

void DiagnosticRenderer::emitStoredDiagnostic(StoredDiagnostic &Diag) {

  emitDiagnostic(Diag.getLocation(), Diag.getLevel(), Diag.getMessage(),

                 Diag.getRanges(), Diag.getFixIts(),

                 &Diag);

}

void DiagnosticRenderer::emitBasicNote(StringRef Message) {

  emitDiagnosticMessage(FullSourceLoc(), PresumedLoc(), DiagnosticsEngine::Note,

                        Message, std::nullopt, DiagOrStoredDiag());

}

/// Prints an include stack when appropriate for a particular

/// diagnostic level and location.

///

/// This routine handles all the logic of suppressing particular include

/// stacks (such as those for notes) and duplicate include stacks when

/// repeated warnings occur within the same file. It also handles the logic

/// of customizing the formatting and display of the include stack.

///

/// \param Loc   The diagnostic location.

/// \param PLoc  The presumed location of the diagnostic location.

/// \param Level The diagnostic level of the message this stack pertains to.

void DiagnosticRenderer::emitIncludeStack(FullSourceLoc Loc, PresumedLoc PLoc,

                                          DiagnosticsEngine::Level Level) {

  FullSourceLoc IncludeLoc =

      PLoc.isInvalid() ? FullSourceLoc()

                       : FullSourceLoc(PLoc.getIncludeLoc(), Loc.getManager());

  // Skip redundant include stacks altogether.

  if (LastIncludeLoc == IncludeLoc)

    return;

  LastIncludeLoc = IncludeLoc;

  if (!DiagOpts->ShowNoteIncludeStack && Level == DiagnosticsEngine::Note)

    return;

  if (IncludeLoc.isValid())

    emitIncludeStackRecursively(IncludeLoc);

  else {

    emitModuleBuildStack(Loc.getManager());

    emitImportStack(Loc);

  }

}

/// Helper to recursively walk up the include stack and print each layer

/// on the way back down.

void DiagnosticRenderer::emitIncludeStackRecursively(FullSourceLoc Loc) {

  if (Loc.isInvalid()) {

    emitModuleBuildStack(Loc.getManager());

    return;

  }

  PresumedLoc PLoc = Loc.getPresumedLoc(DiagOpts->ShowPresumedLoc);

  if (PLoc.isInvalid())

    return;

  // If this source location was imported from a module, print the module

  // import stack rather than the

  // FIXME: We want submodule granularity here.

  std::pair<FullSourceLoc, StringRef> Imported = Loc.getModuleImportLoc();

  if (!Imported.second.empty()) {

    // This location was imported by a module. Emit the module import stack.

    emitImportStackRecursively(Imported.first, Imported.second);

    return;

  }

  // Emit the other include frames first.

  emitIncludeStackRecursively(

      FullSourceLoc(PLoc.getIncludeLoc(), Loc.getManager()));

  // Emit the inclusion text/note.

  emitIncludeLocation(Loc, PLoc);

}

/// Emit the module import stack associated with the current location.

void DiagnosticRenderer::emitImportStack(FullSourceLoc Loc) {

  if (Loc.isInvalid()) {

    emitModuleBuildStack(Loc.getManager());

    return;

  }

  std::pair<FullSourceLoc, StringRef> NextImportLoc = Loc.getModuleImportLoc();

  emitImportStackRecursively(NextImportLoc.first, NextImportLoc.second);

}

/// Helper to recursively walk up the import stack and print each layer

/// on the way back down.

void DiagnosticRenderer::emitImportStackRecursively(FullSourceLoc Loc,

                                                    StringRef ModuleName) {

  if (ModuleName.empty()) {

    return;

  }

  PresumedLoc PLoc = Loc.getPresumedLoc(DiagOpts->ShowPresumedLoc);

  // Emit the other import frames first.

  std::pair<FullSourceLoc, StringRef> NextImportLoc = Loc.getModuleImportLoc();

  emitImportStackRecursively(NextImportLoc.first, NextImportLoc.second);

  // Emit the inclusion text/note.

  emitImportLocation(Loc, PLoc, ModuleName);

}

/// Emit the module build stack, for cases where a module is (re-)built

/// on demand.

void DiagnosticRenderer::emitModuleBuildStack(const SourceManager &SM) {

  ModuleBuildStack Stack = SM.getModuleBuildStack();

  for (const auto &I : Stack) {

    emitBuildingModuleLocation(I.second, I.second.getPresumedLoc(

                                              DiagOpts->ShowPresumedLoc),

                               I.first);

  }

}

/// A recursive function to trace all possible backtrace locations

/// to match the \p CaretLocFileID.

static SourceLocation

retrieveMacroLocation(SourceLocation Loc, FileID MacroFileID,

                      FileID CaretFileID,

                      const SmallVectorImpl<FileID> &CommonArgExpansions,

                      bool IsBegin, const SourceManager *SM,

                      bool &IsTokenRange) {

  assert(SM->getFileID(Loc) == MacroFileID);

  if (MacroFileID == CaretFileID)

    return Loc;

  if (!Loc.isMacroID())

    return {};

  CharSourceRange MacroRange, MacroArgRange;

  if (SM->isMacroArgExpansion(Loc)) {

    // Only look at the immediate spelling location of this macro argument if

    // the other location in the source range is also present in that expansion.

    if (std::binary_search(CommonArgExpansions.begin(),

                           CommonArgExpansions.end(), MacroFileID))

      MacroRange =

          CharSourceRange(SM->getImmediateSpellingLoc(Loc), IsTokenRange);

    MacroArgRange = SM->getImmediateExpansionRange(Loc);

  } else {

    MacroRange = SM->getImmediateExpansionRange(Loc);

    MacroArgRange =

        CharSourceRange(SM->getImmediateSpellingLoc(Loc), IsTokenRange);

  }

  SourceLocation MacroLocation =

      IsBegin ? MacroRange.getBegin() : MacroRange.getEnd();

  if (MacroLocation.isValid()) {

    MacroFileID = SM->getFileID(MacroLocation);

    bool TokenRange = IsBegin ? IsTokenRange : MacroRange.isTokenRange();

    MacroLocation =

        retrieveMacroLocation(MacroLocation, MacroFileID, CaretFileID,

                              CommonArgExpansions, IsBegin, SM, TokenRange);

    if (MacroLocation.isValid()) {

      IsTokenRange = TokenRange;

      return MacroLocation;

    }

  }

  // If we moved the end of the range to an expansion location, we now have

  // a range of the same kind as the expansion range.

  if (!IsBegin)

    IsTokenRange = MacroArgRange.isTokenRange();

  SourceLocation MacroArgLocation =

      IsBegin ? MacroArgRange.getBegin() : MacroArgRange.getEnd();

  MacroFileID = SM->getFileID(MacroArgLocation);

  return retrieveMacroLocation(MacroArgLocation, MacroFileID, CaretFileID,

                               CommonArgExpansions, IsBegin, SM, IsTokenRange);

}

/// Walk up the chain of macro expansions and collect the FileIDs identifying the

/// expansions.

static void getMacroArgExpansionFileIDs(SourceLocation Loc,

                                        SmallVectorImpl<FileID> &IDs,

                                        bool IsBegin, const SourceManager *SM) {

  while (Loc.isMacroID()) {

    if (SM->isMacroArgExpansion(Loc)) {

      IDs.push_back(SM->getFileID(Loc));

      Loc = SM->getImmediateSpellingLoc(Loc);

    } else {

      auto ExpRange = SM->getImmediateExpansionRange(Loc);

      Loc = IsBegin ? ExpRange.getBegin() : ExpRange.getEnd();

    }

  }

}

/// Collect the expansions of the begin and end locations and compute the set

/// intersection. Produces a sorted vector of FileIDs in CommonArgExpansions.

static void computeCommonMacroArgExpansionFileIDs(

    SourceLocation Begin, SourceLocation End, const SourceManager *SM,

    SmallVectorImpl<FileID> &CommonArgExpansions) {

  SmallVector<FileID, 4> BeginArgExpansions;

  SmallVector<FileID, 4> EndArgExpansions;

  getMacroArgExpansionFileIDs(Begin, BeginArgExpansions, /*IsBegin=*/true, SM);

  getMacroArgExpansionFileIDs(End, EndArgExpansions, /*IsBegin=*/false, SM);

  llvm::sort(BeginArgExpansions);

  llvm::sort(EndArgExpansions);

  std::set_intersection(BeginArgExpansions.begin(), BeginArgExpansions.end(),

                        EndArgExpansions.begin(), EndArgExpansions.end(),

                        std::back_inserter(CommonArgExpansions));

}

// Helper function to fix up source ranges.  It takes in an array of ranges,

// and outputs an array of ranges where we want to draw the range highlighting

// around the location specified by CaretLoc.

//

// To find locations which correspond to the caret, we crawl the macro caller

// chain for the beginning and end of each range.  If the caret location

// is in a macro expansion, we search each chain for a location

// in the same expansion as the caret; otherwise, we crawl to the top of

// each chain. Two locations are part of the same macro expansion

// iff the FileID is the same.

static void

mapDiagnosticRanges(FullSourceLoc CaretLoc, ArrayRef<CharSourceRange> Ranges,

                    SmallVectorImpl<CharSourceRange> &SpellingRanges) {

  FileID CaretLocFileID = CaretLoc.getFileID();

  const SourceManager *SM = &CaretLoc.getManager();

  for (const auto &Range : Ranges) {

    if (Range.isInvalid())

      continue;

    SourceLocation Begin = Range.getBegin(), End = Range.getEnd();

    bool IsTokenRange = Range.isTokenRange();

    FileID BeginFileID = SM->getFileID(Begin);

    FileID EndFileID = SM->getFileID(End);

    // Find the common parent for the beginning and end of the range.

    // First, crawl the expansion chain for the beginning of the range.

    llvm::SmallDenseMap<FileID, SourceLocation> BeginLocsMap;

    while (Begin.isMacroID() && BeginFileID != EndFileID) {

      BeginLocsMap[BeginFileID] = Begin;

      Begin = SM->getImmediateExpansionRange(Begin).getBegin();

      BeginFileID = SM->getFileID(Begin);

    }

    // Then, crawl the expansion chain for the end of the range.

    if (BeginFileID != EndFileID) {

      while (End.isMacroID() && !BeginLocsMap.count(EndFileID)) {

        auto Exp = SM->getImmediateExpansionRange(End);

        IsTokenRange = Exp.isTokenRange();

        End = Exp.getEnd();

        EndFileID = SM->getFileID(End);

      }

      if (End.isMacroID()) {

        Begin = BeginLocsMap[EndFileID];

        BeginFileID = EndFileID;

      }

    }

    // There is a chance that begin or end is invalid here, for example if

    // specific compile error is reported.

    // It is possible that the FileID's do not match, if one comes from an

    // included file. In this case we can not produce a meaningful source range.

    if (Begin.isInvalid() || End.isInvalid() || BeginFileID != EndFileID)

      continue;

    // Do the backtracking.

    SmallVector<FileID, 4> CommonArgExpansions;

    computeCommonMacroArgExpansionFileIDs(Begin, End, SM, CommonArgExpansions);

    Begin = retrieveMacroLocation(Begin, BeginFileID, CaretLocFileID,

                                  CommonArgExpansions, /*IsBegin=*/true, SM,

                                  IsTokenRange);

    End = retrieveMacroLocation(End, BeginFileID, CaretLocFileID,

                                CommonArgExpansions, /*IsBegin=*/false, SM,

                                IsTokenRange);

    if (Begin.isInvalid() || End.isInvalid()) continue;

    // Return the spelling location of the beginning and end of the range.

    Begin = SM->getSpellingLoc(Begin);

    End = SM->getSpellingLoc(End);

    SpellingRanges.push_back(CharSourceRange(SourceRange(Begin, End),

                                             IsTokenRange));

  }

}

void DiagnosticRenderer::emitCaret(FullSourceLoc Loc,

                                   DiagnosticsEngine::Level Level,

                                   ArrayRef<CharSourceRange> Ranges,

                                   ArrayRef<FixItHint> Hints) {

  SmallVector<CharSourceRange, 4> SpellingRanges;

  mapDiagnosticRanges(Loc, Ranges, SpellingRanges);

  emitCodeContext(Loc, Level, SpellingRanges, Hints);

}

/// A helper function for emitMacroExpansion to print the

/// macro expansion message

void DiagnosticRenderer::emitSingleMacroExpansion(

    FullSourceLoc Loc, DiagnosticsEngine::Level Level,

    ArrayRef<CharSourceRange> Ranges) {

  // Find the spelling location for the macro definition. We must use the

  // spelling location here to avoid emitting a macro backtrace for the note.

  FullSourceLoc SpellingLoc = Loc.getSpellingLoc();

  // Map the ranges into the FileID of the diagnostic location.

  SmallVector<CharSourceRange, 4> SpellingRanges;

  mapDiagnosticRanges(Loc, Ranges, SpellingRanges);

  SmallString<100> MessageStorage;

  llvm::raw_svector_ostream Message(MessageStorage);

  StringRef MacroName = Lexer::getImmediateMacroNameForDiagnostics(

      Loc, Loc.getManager(), LangOpts);

  if (MacroName.empty())

    Message << "expanded from here";

  else

    Message << "expanded from macro '" << MacroName << "'";

  emitDiagnostic(SpellingLoc, DiagnosticsEngine::Note, Message.str(),

                 SpellingRanges, std::nullopt);

}

/// Check that the macro argument location of Loc starts with ArgumentLoc.

/// The starting location of the macro expansions is used to differeniate

/// different macro expansions.

static bool checkLocForMacroArgExpansion(SourceLocation Loc,

                                         const SourceManager &SM,

                                         SourceLocation ArgumentLoc) {

  SourceLocation MacroLoc;

  if (SM.isMacroArgExpansion(Loc, &MacroLoc)) {

    if (ArgumentLoc == MacroLoc) return true;

  }

  return false;

}

/// Check if all the locations in the range have the same macro argument

/// expansion, and that the expansion starts with ArgumentLoc.

static bool checkRangeForMacroArgExpansion(CharSourceRange Range,

                                           const SourceManager &SM,

                                           SourceLocation ArgumentLoc) {

  SourceLocation BegLoc = Range.getBegin(), EndLoc = Range.getEnd();

  while (BegLoc != EndLoc) {

    if (!checkLocForMacroArgExpansion(BegLoc, SM, ArgumentLoc))

      return false;

    BegLoc.getLocWithOffset(1);

  }

  return checkLocForMacroArgExpansion(BegLoc, SM, ArgumentLoc);

}

/// A helper function to check if the current ranges are all inside the same

/// macro argument expansion as Loc.

static bool checkRangesForMacroArgExpansion(FullSourceLoc Loc,

                                            ArrayRef<CharSourceRange> Ranges) {

  assert(Loc.isMacroID() && "Must be a macro expansion!");

  SmallVector<CharSourceRange, 4> SpellingRanges;

  mapDiagnosticRanges(Loc, Ranges, SpellingRanges);

  // Count all valid ranges.

  unsigned ValidCount =

      llvm::count_if(Ranges, [](const auto &R) { return R.isValid(); });

  if (ValidCount > SpellingRanges.size())

    return false;

  // To store the source location of the argument location.

  FullSourceLoc ArgumentLoc;

  // Set the ArgumentLoc to the beginning location of the expansion of Loc

  // so to check if the ranges expands to the same beginning location.

  if (!Loc.isMacroArgExpansion(&ArgumentLoc))

    return false;

  for (const auto &Range : SpellingRanges)

    if (!checkRangeForMacroArgExpansion(Range, Loc.getManager(), ArgumentLoc))

      return false;

  return true;

}

/// Recursively emit notes for each macro expansion and caret

/// diagnostics where appropriate.

///

/// Walks up the macro expansion stack printing expansion notes, the code

/// snippet, caret, underlines and FixItHint display as appropriate at each

/// level.

///

/// \param Loc The location for this caret.

/// \param Level The diagnostic level currently being emitted.

/// \param Ranges The underlined ranges for this code snippet.

/// \param Hints The FixIt hints active for this diagnostic.

void DiagnosticRenderer::emitMacroExpansions(FullSourceLoc Loc,

                                             DiagnosticsEngine::Level Level,

                                             ArrayRef<CharSourceRange> Ranges,

                                             ArrayRef<FixItHint> Hints) {

  assert(Loc.isValid() && "must have a valid source location here");

  const SourceManager &SM = Loc.getManager();

  SourceLocation L = Loc;

  // Produce a stack of macro backtraces.

  SmallVector<SourceLocation, 8> LocationStack;

  unsigned IgnoredEnd = 0;

  while (L.isMacroID()) {

    // If this is the expansion of a macro argument, point the caret at the

    // use of the argument in the definition of the macro, not the expansion.

    if (SM.isMacroArgExpansion(L))

      LocationStack.push_back(SM.getImmediateExpansionRange(L).getBegin());

    else

      LocationStack.push_back(L);

    if (checkRangesForMacroArgExpansion(FullSourceLoc(L, SM), Ranges))

      IgnoredEnd = LocationStack.size();

    L = SM.getImmediateMacroCallerLoc(L);

    // Once the location no longer points into a macro, try stepping through

    // the last found location.  This sometimes produces additional useful

    // backtraces.

    if (L.isFileID())

      L = SM.getImmediateMacroCallerLoc(LocationStack.back());

    assert(L.isValid() && "must have a valid source location here");

  }

  LocationStack.erase(LocationStack.begin(),

                      LocationStack.begin() + IgnoredEnd);

  unsigned MacroDepth = LocationStack.size();

  unsigned MacroLimit = DiagOpts->MacroBacktraceLimit;

  if (MacroDepth <= MacroLimit || MacroLimit == 0) {

    for (auto I = LocationStack.rbegin(), E = LocationStack.rend();

         I != E; ++I)

      emitSingleMacroExpansion(FullSourceLoc(*I, SM), Level, Ranges);

    return;

  }

  unsigned MacroStartMessages = MacroLimit / 2;

  unsigned MacroEndMessages = MacroLimit / 2 + MacroLimit % 2;

  for (auto I = LocationStack.rbegin(),

            E = LocationStack.rbegin() + MacroStartMessages;

       I != E; ++I)

    emitSingleMacroExpansion(FullSourceLoc(*I, SM), Level, Ranges);

  SmallString<200> MessageStorage;

  llvm::raw_svector_ostream Message(MessageStorage);

  Message << "(skipping " << (MacroDepth - MacroLimit)

          << " expansions in backtrace; use -fmacro-backtrace-limit=0 to "

             "see all)";

  emitBasicNote(Message.str());

  for (auto I = LocationStack.rend() - MacroEndMessages,

            E = LocationStack.rend();

       I != E; ++I)

    emitSingleMacroExpansion(FullSourceLoc(*I, SM), Level, Ranges);

}

DiagnosticNoteRenderer::~DiagnosticNoteRenderer() = default;

void DiagnosticNoteRenderer::emitIncludeLocation(FullSourceLoc Loc,

                                                 PresumedLoc PLoc) {

  // Generate a note indicating the include location.

  SmallString<200> MessageStorage;

  llvm::raw_svector_ostream Message(MessageStorage);

  Message << "in file included from " << PLoc.getFilename() << ':'

          << PLoc.getLine() << ":";

  emitNote(Loc, Message.str());

}

void DiagnosticNoteRenderer::emitImportLocation(FullSourceLoc Loc,

                                                PresumedLoc PLoc,

                                                StringRef ModuleName) {

  // Generate a note indicating the include location.

  SmallString<200> MessageStorage;

  llvm::raw_svector_ostream Message(MessageStorage);

  Message << "in module '" << ModuleName;

  if (PLoc.isValid())

    Message << "' imported from " << PLoc.getFilename() << ':'

            << PLoc.getLine();

  Message << ":";

  emitNote(Loc, Message.str());

}

void DiagnosticNoteRenderer::emitBuildingModuleLocation(FullSourceLoc Loc,

                                                        PresumedLoc PLoc,

                                                        StringRef ModuleName) {

  // Generate a note indicating the include location.

  SmallString<200> MessageStorage;

  llvm::raw_svector_ostream Message(MessageStorage);

  if (PLoc.isValid())

    Message << "while building module '" << ModuleName << "' imported from "

            << PLoc.getFilename() << ':' << PLoc.getLine() << ":";

  else

    Message << "while building module '" << ModuleName << "':";

  emitNote(Loc, Message.str());

}