Preprocessor.cpp revision d6471f7c1921c7802804ce3ff6fe9768310f72b9 
1//===--- Preprocess.cpp - C Language Family Preprocessor Implementation ---===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the Preprocessor interface.
11//
12//===----------------------------------------------------------------------===//
13//
14// Options to support:
15//   -H       - Print the name of each header file used.
16//   -d[DNI] - Dump various things.
17//   -fworking-directory - #line's with preprocessor's working dir.
18//   -fpreprocessed
19//   -dependency-file,-M,-MM,-MF,-MG,-MP,-MT,-MQ,-MD,-MMD
20//   -W*
21//   -w
22//
23// Messages to emit:
24//   "Multiple include guards may be useful for:\n"
25//
26//===----------------------------------------------------------------------===//
27
28#include "clang/Lex/Preprocessor.h"
29#include "MacroArgs.h"
30#include "clang/Lex/ExternalPreprocessorSource.h"
31#include "clang/Lex/HeaderSearch.h"
32#include "clang/Lex/MacroInfo.h"
33#include "clang/Lex/Pragma.h"
34#include "clang/Lex/PreprocessingRecord.h"
35#include "clang/Lex/ScratchBuffer.h"
36#include "clang/Lex/LexDiagnostic.h"
37#include "clang/Lex/CodeCompletionHandler.h"
38#include "clang/Lex/ModuleLoader.h"
39#include "clang/Basic/SourceManager.h"
40#include "clang/Basic/FileManager.h"
41#include "clang/Basic/TargetInfo.h"
42#include "llvm/ADT/APFloat.h"
43#include "llvm/ADT/SmallVector.h"
44#include "llvm/Support/MemoryBuffer.h"
45#include "llvm/Support/raw_ostream.h"
46#include "llvm/Support/Capacity.h"
47using namespace clang;
48
49//===----------------------------------------------------------------------===//
50ExternalPreprocessorSource::~ExternalPreprocessorSource() { }
51
52Preprocessor::Preprocessor(DiagnosticsEngine &diags, LangOptions &opts,
53                           const TargetInfo *target, SourceManager &SM,
54                           HeaderSearch &Headers, ModuleLoader &TheModuleLoader,
55                           IdentifierInfoLookup* IILookup,
56                           bool OwnsHeaders,
57                           bool DelayInitialization)
58  : Diags(&diags), Features(opts), Target(target),FileMgr(Headers.getFileMgr()),
59    SourceMgr(SM), HeaderInfo(Headers), TheModuleLoader(TheModuleLoader),
60    ExternalSource(0),
61    Identifiers(opts, IILookup), CodeComplete(0),
62    CodeCompletionFile(0), CodeCompletionOffset(0), CodeCompletionReached(0),
63    SkipMainFilePreamble(0, true), CurPPLexer(0),
64    CurDirLookup(0), Callbacks(0), MacroArgCache(0), Record(0), MIChainHead(0),
65    MICache(0)
66{
67  OwnsHeaderSearch = OwnsHeaders;
68
69  if (!DelayInitialization) {
70    assert(Target && "Must provide target information for PP initialization");
71    Initialize(*Target);
72  }
73}
74
75Preprocessor::~Preprocessor() {
76  assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!");
77  assert(((MacroExpandingLexersStack.empty() && MacroExpandedTokens.empty()) ||
78          isCodeCompletionReached()) &&
79         "Preprocessor::HandleEndOfTokenLexer should have cleared those");
80
81  while (!IncludeMacroStack.empty()) {
82    delete IncludeMacroStack.back().TheLexer;
83    delete IncludeMacroStack.back().TheTokenLexer;
84    IncludeMacroStack.pop_back();
85  }
86
87  // Free any macro definitions.
88  for (MacroInfoChain *I = MIChainHead ; I ; I = I->Next)
89    I->MI.Destroy();
90
91  // Free any cached macro expanders.
92  for (unsigned i = 0, e = NumCachedTokenLexers; i != e; ++i)
93    delete TokenLexerCache[i];
94
95  // Free any cached MacroArgs.
96  for (MacroArgs *ArgList = MacroArgCache; ArgList; )
97    ArgList = ArgList->deallocate();
98
99  // Release pragma information.
100  delete PragmaHandlers;
101
102  // Delete the scratch buffer info.
103  delete ScratchBuf;
104
105  // Delete the header search info, if we own it.
106  if (OwnsHeaderSearch)
107    delete &HeaderInfo;
108
109  delete Callbacks;
110}
111
112void Preprocessor::Initialize(const TargetInfo &Target) {
113  assert((!this->Target || this->Target == &Target) &&
114         "Invalid override of target information");
115  this->Target = &Target;
116
117  // Initialize information about built-ins.
118  BuiltinInfo.InitializeTarget(Target);
119
120  ScratchBuf = new ScratchBuffer(SourceMgr);
121  CounterValue = 0; // __COUNTER__ starts at 0.
122
123  // Clear stats.
124  NumDirectives = NumDefined = NumUndefined = NumPragma = 0;
125  NumIf = NumElse = NumEndif = 0;
126  NumEnteredSourceFiles = 0;
127  NumMacroExpanded = NumFnMacroExpanded = NumBuiltinMacroExpanded = 0;
128  NumFastMacroExpanded = NumTokenPaste = NumFastTokenPaste = 0;
129  MaxIncludeStackDepth = 0;
130  NumSkipped = 0;
131
132  // Default to discarding comments.
133  KeepComments = false;
134  KeepMacroComments = false;
135  SuppressIncludeNotFoundError = false;
136  AutoModuleImport = false;
137
138  // Macro expansion is enabled.
139  DisableMacroExpansion = false;
140  InMacroArgs = false;
141  NumCachedTokenLexers = 0;
142
143  CachedLexPos = 0;
144
145  // We haven't read anything from the external source.
146  ReadMacrosFromExternalSource = false;
147
148  // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
149  // This gets unpoisoned where it is allowed.
150  (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned();
151  SetPoisonReason(Ident__VA_ARGS__,diag::ext_pp_bad_vaargs_use);
152
153  // Initialize the pragma handlers.
154  PragmaHandlers = new PragmaNamespace(StringRef());
155  RegisterBuiltinPragmas();
156
157  // Initialize builtin macros like __LINE__ and friends.
158  RegisterBuiltinMacros();
159
160  if(Features.Borland) {
161    Ident__exception_info        = getIdentifierInfo("_exception_info");
162    Ident___exception_info       = getIdentifierInfo("__exception_info");
163    Ident_GetExceptionInfo       = getIdentifierInfo("GetExceptionInformation");
164    Ident__exception_code        = getIdentifierInfo("_exception_code");
165    Ident___exception_code       = getIdentifierInfo("__exception_code");
166    Ident_GetExceptionCode       = getIdentifierInfo("GetExceptionCode");
167    Ident__abnormal_termination  = getIdentifierInfo("_abnormal_termination");
168    Ident___abnormal_termination = getIdentifierInfo("__abnormal_termination");
169    Ident_AbnormalTermination    = getIdentifierInfo("AbnormalTermination");
170  } else {
171    Ident__exception_info = Ident__exception_code = Ident__abnormal_termination = 0;
172    Ident___exception_info = Ident___exception_code = Ident___abnormal_termination = 0;
173    Ident_GetExceptionInfo = Ident_GetExceptionCode = Ident_AbnormalTermination = 0;
174  }
175}
176
177void Preprocessor::setPTHManager(PTHManager* pm) {
178  PTH.reset(pm);
179  FileMgr.addStatCache(PTH->createStatCache());
180}
181
182void Preprocessor::DumpToken(const Token &Tok, bool DumpFlags) const {
183  llvm::errs() << tok::getTokenName(Tok.getKind()) << " '"
184               << getSpelling(Tok) << "'";
185
186  if (!DumpFlags) return;
187
188  llvm::errs() << "\t";
189  if (Tok.isAtStartOfLine())
190    llvm::errs() << " [StartOfLine]";
191  if (Tok.hasLeadingSpace())
192    llvm::errs() << " [LeadingSpace]";
193  if (Tok.isExpandDisabled())
194    llvm::errs() << " [ExpandDisabled]";
195  if (Tok.needsCleaning()) {
196    const char *Start = SourceMgr.getCharacterData(Tok.getLocation());
197    llvm::errs() << " [UnClean='" << StringRef(Start, Tok.getLength())
198                 << "']";
199  }
200
201  llvm::errs() << "\tLoc=<";
202  DumpLocation(Tok.getLocation());
203  llvm::errs() << ">";
204}
205
206void Preprocessor::DumpLocation(SourceLocation Loc) const {
207  Loc.dump(SourceMgr);
208}
209
210void Preprocessor::DumpMacro(const MacroInfo &MI) const {
211  llvm::errs() << "MACRO: ";
212  for (unsigned i = 0, e = MI.getNumTokens(); i != e; ++i) {
213    DumpToken(MI.getReplacementToken(i));
214    llvm::errs() << "  ";
215  }
216  llvm::errs() << "\n";
217}
218
219void Preprocessor::PrintStats() {
220  llvm::errs() << "\n*** Preprocessor Stats:\n";
221  llvm::errs() << NumDirectives << " directives found:\n";
222  llvm::errs() << "  " << NumDefined << " #define.\n";
223  llvm::errs() << "  " << NumUndefined << " #undef.\n";
224  llvm::errs() << "  #include/#include_next/#import:\n";
225  llvm::errs() << "    " << NumEnteredSourceFiles << " source files entered.\n";
226  llvm::errs() << "    " << MaxIncludeStackDepth << " max include stack depth\n";
227  llvm::errs() << "  " << NumIf << " #if/#ifndef/#ifdef.\n";
228  llvm::errs() << "  " << NumElse << " #else/#elif.\n";
229  llvm::errs() << "  " << NumEndif << " #endif.\n";
230  llvm::errs() << "  " << NumPragma << " #pragma.\n";
231  llvm::errs() << NumSkipped << " #if/#ifndef#ifdef regions skipped\n";
232
233  llvm::errs() << NumMacroExpanded << "/" << NumFnMacroExpanded << "/"
234             << NumBuiltinMacroExpanded << " obj/fn/builtin macros expanded, "
235             << NumFastMacroExpanded << " on the fast path.\n";
236  llvm::errs() << (NumFastTokenPaste+NumTokenPaste)
237             << " token paste (##) operations performed, "
238             << NumFastTokenPaste << " on the fast path.\n";
239}
240
241Preprocessor::macro_iterator
242Preprocessor::macro_begin(bool IncludeExternalMacros) const {
243  if (IncludeExternalMacros && ExternalSource &&
244      !ReadMacrosFromExternalSource) {
245    ReadMacrosFromExternalSource = true;
246    ExternalSource->ReadDefinedMacros();
247  }
248
249  return Macros.begin();
250}
251
252size_t Preprocessor::getTotalMemory() const {
253  return BP.getTotalMemory()
254    + llvm::capacity_in_bytes(MacroExpandedTokens)
255    + Predefines.capacity() /* Predefines buffer. */
256    + llvm::capacity_in_bytes(Macros)
257    + llvm::capacity_in_bytes(PragmaPushMacroInfo)
258    + llvm::capacity_in_bytes(PoisonReasons)
259    + llvm::capacity_in_bytes(CommentHandlers);
260}
261
262Preprocessor::macro_iterator
263Preprocessor::macro_end(bool IncludeExternalMacros) const {
264  if (IncludeExternalMacros && ExternalSource &&
265      !ReadMacrosFromExternalSource) {
266    ReadMacrosFromExternalSource = true;
267    ExternalSource->ReadDefinedMacros();
268  }
269
270  return Macros.end();
271}
272
273bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File,
274                                          unsigned CompleteLine,
275                                          unsigned CompleteColumn) {
276  assert(File);
277  assert(CompleteLine && CompleteColumn && "Starts from 1:1");
278  assert(!CodeCompletionFile && "Already set");
279
280  using llvm::MemoryBuffer;
281
282  // Load the actual file's contents.
283  bool Invalid = false;
284  const MemoryBuffer *Buffer = SourceMgr.getMemoryBufferForFile(File, &Invalid);
285  if (Invalid)
286    return true;
287
288  // Find the byte position of the truncation point.
289  const char *Position = Buffer->getBufferStart();
290  for (unsigned Line = 1; Line < CompleteLine; ++Line) {
291    for (; *Position; ++Position) {
292      if (*Position != '\r' && *Position != '\n')
293        continue;
294
295      // Eat \r\n or \n\r as a single line.
296      if ((Position[1] == '\r' || Position[1] == '\n') &&
297          Position[0] != Position[1])
298        ++Position;
299      ++Position;
300      break;
301    }
302  }
303
304  Position += CompleteColumn - 1;
305
306  // Insert '\0' at the code-completion point.
307  if (Position < Buffer->getBufferEnd()) {
308    CodeCompletionFile = File;
309    CodeCompletionOffset = Position - Buffer->getBufferStart();
310
311    MemoryBuffer *NewBuffer =
312        MemoryBuffer::getNewUninitMemBuffer(Buffer->getBufferSize() + 1,
313                                            Buffer->getBufferIdentifier());
314    char *NewBuf = const_cast<char*>(NewBuffer->getBufferStart());
315    char *NewPos = std::copy(Buffer->getBufferStart(), Position, NewBuf);
316    *NewPos = '\0';
317    std::copy(Position, Buffer->getBufferEnd(), NewPos+1);
318    SourceMgr.overrideFileContents(File, NewBuffer);
319  }
320
321  return false;
322}
323
324void Preprocessor::CodeCompleteNaturalLanguage() {
325  if (CodeComplete)
326    CodeComplete->CodeCompleteNaturalLanguage();
327  setCodeCompletionReached();
328}
329
330/// getSpelling - This method is used to get the spelling of a token into a
331/// SmallVector. Note that the returned StringRef may not point to the
332/// supplied buffer if a copy can be avoided.
333StringRef Preprocessor::getSpelling(const Token &Tok,
334                                          SmallVectorImpl<char> &Buffer,
335                                          bool *Invalid) const {
336  // NOTE: this has to be checked *before* testing for an IdentifierInfo.
337  if (Tok.isNot(tok::raw_identifier)) {
338    // Try the fast path.
339    if (const IdentifierInfo *II = Tok.getIdentifierInfo())
340      return II->getName();
341  }
342
343  // Resize the buffer if we need to copy into it.
344  if (Tok.needsCleaning())
345    Buffer.resize(Tok.getLength());
346
347  const char *Ptr = Buffer.data();
348  unsigned Len = getSpelling(Tok, Ptr, Invalid);
349  return StringRef(Ptr, Len);
350}
351
352/// CreateString - Plop the specified string into a scratch buffer and return a
353/// location for it.  If specified, the source location provides a source
354/// location for the token.
355void Preprocessor::CreateString(const char *Buf, unsigned Len, Token &Tok,
356                                SourceLocation ExpansionLoc) {
357  Tok.setLength(Len);
358
359  const char *DestPtr;
360  SourceLocation Loc = ScratchBuf->getToken(Buf, Len, DestPtr);
361
362  if (ExpansionLoc.isValid())
363    Loc = SourceMgr.createExpansionLoc(Loc, ExpansionLoc, ExpansionLoc, Len);
364  Tok.setLocation(Loc);
365
366  // If this is a raw identifier or a literal token, set the pointer data.
367  if (Tok.is(tok::raw_identifier))
368    Tok.setRawIdentifierData(DestPtr);
369  else if (Tok.isLiteral())
370    Tok.setLiteralData(DestPtr);
371}
372
373
374
375//===----------------------------------------------------------------------===//
376// Preprocessor Initialization Methods
377//===----------------------------------------------------------------------===//
378
379
380/// EnterMainSourceFile - Enter the specified FileID as the main source file,
381/// which implicitly adds the builtin defines etc.
382void Preprocessor::EnterMainSourceFile() {
383  // We do not allow the preprocessor to reenter the main file.  Doing so will
384  // cause FileID's to accumulate information from both runs (e.g. #line
385  // information) and predefined macros aren't guaranteed to be set properly.
386  assert(NumEnteredSourceFiles == 0 && "Cannot reenter the main file!");
387  FileID MainFileID = SourceMgr.getMainFileID();
388
389  // Enter the main file source buffer.
390  EnterSourceFile(MainFileID, 0, SourceLocation());
391
392  // If we've been asked to skip bytes in the main file (e.g., as part of a
393  // precompiled preamble), do so now.
394  if (SkipMainFilePreamble.first > 0)
395    CurLexer->SkipBytes(SkipMainFilePreamble.first,
396                        SkipMainFilePreamble.second);
397
398  // Tell the header info that the main file was entered.  If the file is later
399  // #imported, it won't be re-entered.
400  if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID))
401    HeaderInfo.IncrementIncludeCount(FE);
402
403  // Preprocess Predefines to populate the initial preprocessor state.
404  llvm::MemoryBuffer *SB =
405    llvm::MemoryBuffer::getMemBufferCopy(Predefines, "<built-in>");
406  assert(SB && "Cannot create predefined source buffer");
407  FileID FID = SourceMgr.createFileIDForMemBuffer(SB);
408  assert(!FID.isInvalid() && "Could not create FileID for predefines?");
409
410  // Start parsing the predefines.
411  EnterSourceFile(FID, 0, SourceLocation());
412}
413
414void Preprocessor::EndSourceFile() {
415  // Notify the client that we reached the end of the source file.
416  if (Callbacks)
417    Callbacks->EndOfMainFile();
418}
419
420//===----------------------------------------------------------------------===//
421// Lexer Event Handling.
422//===----------------------------------------------------------------------===//
423
424/// LookUpIdentifierInfo - Given a tok::raw_identifier token, look up the
425/// identifier information for the token and install it into the token,
426/// updating the token kind accordingly.
427IdentifierInfo *Preprocessor::LookUpIdentifierInfo(Token &Identifier) const {
428  assert(Identifier.getRawIdentifierData() != 0 && "No raw identifier data!");
429
430  // Look up this token, see if it is a macro, or if it is a language keyword.
431  IdentifierInfo *II;
432  if (!Identifier.needsCleaning()) {
433    // No cleaning needed, just use the characters from the lexed buffer.
434    II = getIdentifierInfo(StringRef(Identifier.getRawIdentifierData(),
435                                           Identifier.getLength()));
436  } else {
437    // Cleaning needed, alloca a buffer, clean into it, then use the buffer.
438    llvm::SmallString<64> IdentifierBuffer;
439    StringRef CleanedStr = getSpelling(Identifier, IdentifierBuffer);
440    II = getIdentifierInfo(CleanedStr);
441  }
442
443  // Update the token info (identifier info and appropriate token kind).
444  Identifier.setIdentifierInfo(II);
445  Identifier.setKind(II->getTokenID());
446
447  return II;
448}
449
450void Preprocessor::SetPoisonReason(IdentifierInfo *II, unsigned DiagID) {
451  PoisonReasons[II] = DiagID;
452}
453
454void Preprocessor::PoisonSEHIdentifiers(bool Poison) {
455  assert(Ident__exception_code && Ident__exception_info);
456  assert(Ident___exception_code && Ident___exception_info);
457  Ident__exception_code->setIsPoisoned(Poison);
458  Ident___exception_code->setIsPoisoned(Poison);
459  Ident_GetExceptionCode->setIsPoisoned(Poison);
460  Ident__exception_info->setIsPoisoned(Poison);
461  Ident___exception_info->setIsPoisoned(Poison);
462  Ident_GetExceptionInfo->setIsPoisoned(Poison);
463  Ident__abnormal_termination->setIsPoisoned(Poison);
464  Ident___abnormal_termination->setIsPoisoned(Poison);
465  Ident_AbnormalTermination->setIsPoisoned(Poison);
466}
467
468void Preprocessor::HandlePoisonedIdentifier(Token & Identifier) {
469  assert(Identifier.getIdentifierInfo() &&
470         "Can't handle identifiers without identifier info!");
471  llvm::DenseMap<IdentifierInfo*,unsigned>::const_iterator it =
472    PoisonReasons.find(Identifier.getIdentifierInfo());
473  if(it == PoisonReasons.end())
474    Diag(Identifier, diag::err_pp_used_poisoned_id);
475  else
476    Diag(Identifier,it->second) << Identifier.getIdentifierInfo();
477}
478
479/// HandleIdentifier - This callback is invoked when the lexer reads an
480/// identifier.  This callback looks up the identifier in the map and/or
481/// potentially macro expands it or turns it into a named token (like 'for').
482///
483/// Note that callers of this method are guarded by checking the
484/// IdentifierInfo's 'isHandleIdentifierCase' bit.  If this method changes, the
485/// IdentifierInfo methods that compute these properties will need to change to
486/// match.
487void Preprocessor::HandleIdentifier(Token &Identifier) {
488  assert(Identifier.getIdentifierInfo() &&
489         "Can't handle identifiers without identifier info!");
490
491  IdentifierInfo &II = *Identifier.getIdentifierInfo();
492
493  // If this identifier was poisoned, and if it was not produced from a macro
494  // expansion, emit an error.
495  if (II.isPoisoned() && CurPPLexer) {
496    HandlePoisonedIdentifier(Identifier);
497  }
498
499  // If this is a macro to be expanded, do it.
500  if (MacroInfo *MI = getMacroInfo(&II)) {
501    if (!DisableMacroExpansion && !Identifier.isExpandDisabled()) {
502      if (MI->isEnabled()) {
503        if (!HandleMacroExpandedIdentifier(Identifier, MI))
504          return;
505      } else {
506        // C99 6.10.3.4p2 says that a disabled macro may never again be
507        // expanded, even if it's in a context where it could be expanded in the
508        // future.
509        Identifier.setFlag(Token::DisableExpand);
510      }
511    }
512  }
513
514  // C++ 2.11p2: If this is an alternative representation of a C++ operator,
515  // then we act as if it is the actual operator and not the textual
516  // representation of it.
517  if (II.isCPlusPlusOperatorKeyword())
518    Identifier.setIdentifierInfo(0);
519
520  // If this is an extension token, diagnose its use.
521  // We avoid diagnosing tokens that originate from macro definitions.
522  // FIXME: This warning is disabled in cases where it shouldn't be,
523  // like "#define TY typeof", "TY(1) x".
524  if (II.isExtensionToken() && !DisableMacroExpansion)
525    Diag(Identifier, diag::ext_token_used);
526
527  // If this is the '__import_module__' keyword, note that the next token
528  // indicates a module name.
529  if (II.getTokenID() == tok::kw___import_module__ &&
530      !InMacroArgs && !DisableMacroExpansion) {
531    ModuleImportLoc = Identifier.getLocation();
532    CurLexerKind = CLK_LexAfterModuleImport;
533  }
534}
535
536/// \brief Lex a token following the __import_module__ keyword.
537void Preprocessor::LexAfterModuleImport(Token &Result) {
538  // Figure out what kind of lexer we actually have.
539  if (CurLexer)
540    CurLexerKind = CLK_Lexer;
541  else if (CurPTHLexer)
542    CurLexerKind = CLK_PTHLexer;
543  else if (CurTokenLexer)
544    CurLexerKind = CLK_TokenLexer;
545  else
546    CurLexerKind = CLK_CachingLexer;
547
548  // Lex the next token.
549  Lex(Result);
550
551  // The token sequence
552  //
553  //   __import_module__ identifier
554  //
555  // indicates a module import directive. We already saw the __import_module__
556  // keyword, so now we're looking for the identifier.
557  if (Result.getKind() != tok::identifier)
558    return;
559
560  // Load the module.
561  (void)TheModuleLoader.loadModule(ModuleImportLoc,
562                                   *Result.getIdentifierInfo(),
563                                   Result.getLocation());
564}
565
566void Preprocessor::AddCommentHandler(CommentHandler *Handler) {
567  assert(Handler && "NULL comment handler");
568  assert(std::find(CommentHandlers.begin(), CommentHandlers.end(), Handler) ==
569         CommentHandlers.end() && "Comment handler already registered");
570  CommentHandlers.push_back(Handler);
571}
572
573void Preprocessor::RemoveCommentHandler(CommentHandler *Handler) {
574  std::vector<CommentHandler *>::iterator Pos
575  = std::find(CommentHandlers.begin(), CommentHandlers.end(), Handler);
576  assert(Pos != CommentHandlers.end() && "Comment handler not registered");
577  CommentHandlers.erase(Pos);
578}
579
580bool Preprocessor::HandleComment(Token &result, SourceRange Comment) {
581  bool AnyPendingTokens = false;
582  for (std::vector<CommentHandler *>::iterator H = CommentHandlers.begin(),
583       HEnd = CommentHandlers.end();
584       H != HEnd; ++H) {
585    if ((*H)->HandleComment(*this, Comment))
586      AnyPendingTokens = true;
587  }
588  if (!AnyPendingTokens || getCommentRetentionState())
589    return false;
590  Lex(result);
591  return true;
592}
593
594ModuleLoader::~ModuleLoader() { }
595
596CommentHandler::~CommentHandler() { }
597
598CodeCompletionHandler::~CodeCompletionHandler() { }
599
600void Preprocessor::createPreprocessingRecord(
601                                      bool IncludeNestedMacroExpansions) {
602  if (Record)
603    return;
604
605  Record = new PreprocessingRecord(getSourceManager(),
606                                   IncludeNestedMacroExpansions);
607  addPPCallbacks(Record);
608}
609