xref: /freebsd/contrib/llvm-project/clang/lib/Lex/TokenLexer.cpp (revision c7a063741720ef81d4caa4613242579d12f1d605)
1 //===- TokenLexer.cpp - Lex from a token stream ---------------------------===//
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 implements the TokenLexer interface.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Lex/TokenLexer.h"
14 #include "clang/Basic/Diagnostic.h"
15 #include "clang/Basic/IdentifierTable.h"
16 #include "clang/Basic/LangOptions.h"
17 #include "clang/Basic/SourceLocation.h"
18 #include "clang/Basic/SourceManager.h"
19 #include "clang/Basic/TokenKinds.h"
20 #include "clang/Lex/LexDiagnostic.h"
21 #include "clang/Lex/Lexer.h"
22 #include "clang/Lex/MacroArgs.h"
23 #include "clang/Lex/MacroInfo.h"
24 #include "clang/Lex/Preprocessor.h"
25 #include "clang/Lex/Token.h"
26 #include "clang/Lex/VariadicMacroSupport.h"
27 #include "llvm/ADT/ArrayRef.h"
28 #include "llvm/ADT/SmallString.h"
29 #include "llvm/ADT/SmallVector.h"
30 #include "llvm/ADT/iterator_range.h"
31 #include <cassert>
32 #include <cstring>
33 
34 using namespace clang;
35 
36 /// Create a TokenLexer for the specified macro with the specified actual
37 /// arguments.  Note that this ctor takes ownership of the ActualArgs pointer.
38 void TokenLexer::Init(Token &Tok, SourceLocation ELEnd, MacroInfo *MI,
39                       MacroArgs *Actuals) {
40   // If the client is reusing a TokenLexer, make sure to free any memory
41   // associated with it.
42   destroy();
43 
44   Macro = MI;
45   ActualArgs = Actuals;
46   CurTokenIdx = 0;
47 
48   ExpandLocStart = Tok.getLocation();
49   ExpandLocEnd = ELEnd;
50   AtStartOfLine = Tok.isAtStartOfLine();
51   HasLeadingSpace = Tok.hasLeadingSpace();
52   NextTokGetsSpace = false;
53   Tokens = &*Macro->tokens_begin();
54   OwnsTokens = false;
55   DisableMacroExpansion = false;
56   IsReinject = false;
57   NumTokens = Macro->tokens_end()-Macro->tokens_begin();
58   MacroExpansionStart = SourceLocation();
59 
60   SourceManager &SM = PP.getSourceManager();
61   MacroStartSLocOffset = SM.getNextLocalOffset();
62 
63   if (NumTokens > 0) {
64     assert(Tokens[0].getLocation().isValid());
65     assert((Tokens[0].getLocation().isFileID() || Tokens[0].is(tok::comment)) &&
66            "Macro defined in macro?");
67     assert(ExpandLocStart.isValid());
68 
69     // Reserve a source location entry chunk for the length of the macro
70     // definition. Tokens that get lexed directly from the definition will
71     // have their locations pointing inside this chunk. This is to avoid
72     // creating separate source location entries for each token.
73     MacroDefStart = SM.getExpansionLoc(Tokens[0].getLocation());
74     MacroDefLength = Macro->getDefinitionLength(SM);
75     MacroExpansionStart = SM.createExpansionLoc(MacroDefStart,
76                                                 ExpandLocStart,
77                                                 ExpandLocEnd,
78                                                 MacroDefLength);
79   }
80 
81   // If this is a function-like macro, expand the arguments and change
82   // Tokens to point to the expanded tokens.
83   if (Macro->isFunctionLike() && Macro->getNumParams())
84     ExpandFunctionArguments();
85 
86   // Mark the macro as currently disabled, so that it is not recursively
87   // expanded.  The macro must be disabled only after argument pre-expansion of
88   // function-like macro arguments occurs.
89   Macro->DisableMacro();
90 }
91 
92 /// Create a TokenLexer for the specified token stream.  This does not
93 /// take ownership of the specified token vector.
94 void TokenLexer::Init(const Token *TokArray, unsigned NumToks,
95                       bool disableMacroExpansion, bool ownsTokens,
96                       bool isReinject) {
97   assert(!isReinject || disableMacroExpansion);
98   // If the client is reusing a TokenLexer, make sure to free any memory
99   // associated with it.
100   destroy();
101 
102   Macro = nullptr;
103   ActualArgs = nullptr;
104   Tokens = TokArray;
105   OwnsTokens = ownsTokens;
106   DisableMacroExpansion = disableMacroExpansion;
107   IsReinject = isReinject;
108   NumTokens = NumToks;
109   CurTokenIdx = 0;
110   ExpandLocStart = ExpandLocEnd = SourceLocation();
111   AtStartOfLine = false;
112   HasLeadingSpace = false;
113   NextTokGetsSpace = false;
114   MacroExpansionStart = SourceLocation();
115 
116   // Set HasLeadingSpace/AtStartOfLine so that the first token will be
117   // returned unmodified.
118   if (NumToks != 0) {
119     AtStartOfLine   = TokArray[0].isAtStartOfLine();
120     HasLeadingSpace = TokArray[0].hasLeadingSpace();
121   }
122 }
123 
124 void TokenLexer::destroy() {
125   // If this was a function-like macro that actually uses its arguments, delete
126   // the expanded tokens.
127   if (OwnsTokens) {
128     delete [] Tokens;
129     Tokens = nullptr;
130     OwnsTokens = false;
131   }
132 
133   // TokenLexer owns its formal arguments.
134   if (ActualArgs) ActualArgs->destroy(PP);
135 }
136 
137 bool TokenLexer::MaybeRemoveCommaBeforeVaArgs(
138     SmallVectorImpl<Token> &ResultToks, bool HasPasteOperator, MacroInfo *Macro,
139     unsigned MacroArgNo, Preprocessor &PP) {
140   // Is the macro argument __VA_ARGS__?
141   if (!Macro->isVariadic() || MacroArgNo != Macro->getNumParams()-1)
142     return false;
143 
144   // In Microsoft-compatibility mode, a comma is removed in the expansion
145   // of " ... , __VA_ARGS__ " if __VA_ARGS__ is empty.  This extension is
146   // not supported by gcc.
147   if (!HasPasteOperator && !PP.getLangOpts().MSVCCompat)
148     return false;
149 
150   // GCC removes the comma in the expansion of " ... , ## __VA_ARGS__ " if
151   // __VA_ARGS__ is empty, but not in strict C99 mode where there are no
152   // named arguments, where it remains.  In all other modes, including C99
153   // with GNU extensions, it is removed regardless of named arguments.
154   // Microsoft also appears to support this extension, unofficially.
155   if (PP.getLangOpts().C99 && !PP.getLangOpts().GNUMode
156         && Macro->getNumParams() < 2)
157     return false;
158 
159   // Is a comma available to be removed?
160   if (ResultToks.empty() || !ResultToks.back().is(tok::comma))
161     return false;
162 
163   // Issue an extension diagnostic for the paste operator.
164   if (HasPasteOperator)
165     PP.Diag(ResultToks.back().getLocation(), diag::ext_paste_comma);
166 
167   // Remove the comma.
168   ResultToks.pop_back();
169 
170   if (!ResultToks.empty()) {
171     // If the comma was right after another paste (e.g. "X##,##__VA_ARGS__"),
172     // then removal of the comma should produce a placemarker token (in C99
173     // terms) which we model by popping off the previous ##, giving us a plain
174     // "X" when __VA_ARGS__ is empty.
175     if (ResultToks.back().is(tok::hashhash))
176       ResultToks.pop_back();
177 
178     // Remember that this comma was elided.
179     ResultToks.back().setFlag(Token::CommaAfterElided);
180   }
181 
182   // Never add a space, even if the comma, ##, or arg had a space.
183   NextTokGetsSpace = false;
184   return true;
185 }
186 
187 void TokenLexer::stringifyVAOPTContents(
188     SmallVectorImpl<Token> &ResultToks, const VAOptExpansionContext &VCtx,
189     const SourceLocation VAOPTClosingParenLoc) {
190   const int NumToksPriorToVAOpt = VCtx.getNumberOfTokensPriorToVAOpt();
191   const unsigned int NumVAOptTokens = ResultToks.size() - NumToksPriorToVAOpt;
192   Token *const VAOPTTokens =
193       NumVAOptTokens ? &ResultToks[NumToksPriorToVAOpt] : nullptr;
194 
195   SmallVector<Token, 64> ConcatenatedVAOPTResultToks;
196   // FIXME: Should we keep track within VCtx that we did or didnot
197   // encounter pasting - and only then perform this loop.
198 
199   // Perform token pasting (concatenation) prior to stringization.
200   for (unsigned int CurTokenIdx = 0; CurTokenIdx != NumVAOptTokens;
201        ++CurTokenIdx) {
202     if (VAOPTTokens[CurTokenIdx].is(tok::hashhash)) {
203       assert(CurTokenIdx != 0 &&
204              "Can not have __VAOPT__ contents begin with a ##");
205       Token &LHS = VAOPTTokens[CurTokenIdx - 1];
206       pasteTokens(LHS, llvm::makeArrayRef(VAOPTTokens, NumVAOptTokens),
207                   CurTokenIdx);
208       // Replace the token prior to the first ## in this iteration.
209       ConcatenatedVAOPTResultToks.back() = LHS;
210       if (CurTokenIdx == NumVAOptTokens)
211         break;
212     }
213     ConcatenatedVAOPTResultToks.push_back(VAOPTTokens[CurTokenIdx]);
214   }
215 
216   ConcatenatedVAOPTResultToks.push_back(VCtx.getEOFTok());
217   // Get the SourceLocation that represents the start location within
218   // the macro definition that marks where this string is substituted
219   // into: i.e. the __VA_OPT__ and the ')' within the spelling of the
220   // macro definition, and use it to indicate that the stringified token
221   // was generated from that location.
222   const SourceLocation ExpansionLocStartWithinMacro =
223       getExpansionLocForMacroDefLoc(VCtx.getVAOptLoc());
224   const SourceLocation ExpansionLocEndWithinMacro =
225       getExpansionLocForMacroDefLoc(VAOPTClosingParenLoc);
226 
227   Token StringifiedVAOPT = MacroArgs::StringifyArgument(
228       &ConcatenatedVAOPTResultToks[0], PP, VCtx.hasCharifyBefore() /*Charify*/,
229       ExpansionLocStartWithinMacro, ExpansionLocEndWithinMacro);
230 
231   if (VCtx.getLeadingSpaceForStringifiedToken())
232     StringifiedVAOPT.setFlag(Token::LeadingSpace);
233 
234   StringifiedVAOPT.setFlag(Token::StringifiedInMacro);
235   // Resize (shrink) the token stream to just capture this stringified token.
236   ResultToks.resize(NumToksPriorToVAOpt + 1);
237   ResultToks.back() = StringifiedVAOPT;
238 }
239 
240 /// Expand the arguments of a function-like macro so that we can quickly
241 /// return preexpanded tokens from Tokens.
242 void TokenLexer::ExpandFunctionArguments() {
243   SmallVector<Token, 128> ResultToks;
244 
245   // Loop through 'Tokens', expanding them into ResultToks.  Keep
246   // track of whether we change anything.  If not, no need to keep them.  If so,
247   // we install the newly expanded sequence as the new 'Tokens' list.
248   bool MadeChange = false;
249 
250   Optional<bool> CalledWithVariadicArguments;
251 
252   VAOptExpansionContext VCtx(PP);
253 
254   for (unsigned I = 0, E = NumTokens; I != E; ++I) {
255     const Token &CurTok = Tokens[I];
256     // We don't want a space for the next token after a paste
257     // operator.  In valid code, the token will get smooshed onto the
258     // preceding one anyway. In assembler-with-cpp mode, invalid
259     // pastes are allowed through: in this case, we do not want the
260     // extra whitespace to be added.  For example, we want ". ## foo"
261     // -> ".foo" not ". foo".
262     if (I != 0 && !Tokens[I-1].is(tok::hashhash) && CurTok.hasLeadingSpace())
263       NextTokGetsSpace = true;
264 
265     if (VCtx.isVAOptToken(CurTok)) {
266       MadeChange = true;
267       assert(Tokens[I + 1].is(tok::l_paren) &&
268              "__VA_OPT__ must be followed by '('");
269 
270       ++I;             // Skip the l_paren
271       VCtx.sawVAOptFollowedByOpeningParens(CurTok.getLocation(),
272                                            ResultToks.size());
273 
274       continue;
275     }
276 
277     // We have entered into the __VA_OPT__ context, so handle tokens
278     // appropriately.
279     if (VCtx.isInVAOpt()) {
280       // If we are about to process a token that is either an argument to
281       // __VA_OPT__ or its closing rparen, then:
282       //  1) If the token is the closing rparen that exits us out of __VA_OPT__,
283       //  perform any necessary stringification or placemarker processing,
284       //  and/or skip to the next token.
285       //  2) else if macro was invoked without variadic arguments skip this
286       //  token.
287       //  3) else (macro was invoked with variadic arguments) process the token
288       //  normally.
289 
290       if (Tokens[I].is(tok::l_paren))
291         VCtx.sawOpeningParen(Tokens[I].getLocation());
292       // Continue skipping tokens within __VA_OPT__ if the macro was not
293       // called with variadic arguments, else let the rest of the loop handle
294       // this token. Note sawClosingParen() returns true only if the r_paren matches
295       // the closing r_paren of the __VA_OPT__.
296       if (!Tokens[I].is(tok::r_paren) || !VCtx.sawClosingParen()) {
297         // Lazily expand __VA_ARGS__ when we see the first __VA_OPT__.
298         if (!CalledWithVariadicArguments.hasValue()) {
299           CalledWithVariadicArguments =
300               ActualArgs->invokedWithVariadicArgument(Macro, PP);
301         }
302         if (!*CalledWithVariadicArguments) {
303           // Skip this token.
304           continue;
305         }
306         // ... else the macro was called with variadic arguments, and we do not
307         // have a closing rparen - so process this token normally.
308       } else {
309         // Current token is the closing r_paren which marks the end of the
310         // __VA_OPT__ invocation, so handle any place-marker pasting (if
311         // empty) by removing hashhash either before (if exists) or after. And
312         // also stringify the entire contents if VAOPT was preceded by a hash,
313         // but do so only after any token concatenation that needs to occur
314         // within the contents of VAOPT.
315 
316         if (VCtx.hasStringifyOrCharifyBefore()) {
317           // Replace all the tokens just added from within VAOPT into a single
318           // stringified token. This requires token-pasting to eagerly occur
319           // within these tokens. If either the contents of VAOPT were empty
320           // or the macro wasn't called with any variadic arguments, the result
321           // is a token that represents an empty string.
322           stringifyVAOPTContents(ResultToks, VCtx,
323                                  /*ClosingParenLoc*/ Tokens[I].getLocation());
324 
325         } else if (/*No tokens within VAOPT*/
326                    ResultToks.size() == VCtx.getNumberOfTokensPriorToVAOpt()) {
327           // Treat VAOPT as a placemarker token.  Eat either the '##' before the
328           // RHS/VAOPT (if one exists, suggesting that the LHS (if any) to that
329           // hashhash was not a placemarker) or the '##'
330           // after VAOPT, but not both.
331 
332           if (ResultToks.size() && ResultToks.back().is(tok::hashhash)) {
333             ResultToks.pop_back();
334           } else if ((I + 1 != E) && Tokens[I + 1].is(tok::hashhash)) {
335             ++I; // Skip the following hashhash.
336           }
337         } else {
338           // If there's a ## before the __VA_OPT__, we might have discovered
339           // that the __VA_OPT__ begins with a placeholder. We delay action on
340           // that to now to avoid messing up our stashed count of tokens before
341           // __VA_OPT__.
342           if (VCtx.beginsWithPlaceholder()) {
343             assert(VCtx.getNumberOfTokensPriorToVAOpt() > 0 &&
344                    ResultToks.size() >= VCtx.getNumberOfTokensPriorToVAOpt() &&
345                    ResultToks[VCtx.getNumberOfTokensPriorToVAOpt() - 1].is(
346                        tok::hashhash) &&
347                    "no token paste before __VA_OPT__");
348             ResultToks.erase(ResultToks.begin() +
349                              VCtx.getNumberOfTokensPriorToVAOpt() - 1);
350           }
351           // If the expansion of __VA_OPT__ ends with a placeholder, eat any
352           // following '##' token.
353           if (VCtx.endsWithPlaceholder() && I + 1 != E &&
354               Tokens[I + 1].is(tok::hashhash)) {
355             ++I;
356           }
357         }
358         VCtx.reset();
359         // We processed __VA_OPT__'s closing paren (and the exit out of
360         // __VA_OPT__), so skip to the next token.
361         continue;
362       }
363     }
364 
365     // If we found the stringify operator, get the argument stringified.  The
366     // preprocessor already verified that the following token is a macro
367     // parameter or __VA_OPT__ when the #define was lexed.
368 
369     if (CurTok.isOneOf(tok::hash, tok::hashat)) {
370       int ArgNo = Macro->getParameterNum(Tokens[I+1].getIdentifierInfo());
371       assert((ArgNo != -1 || VCtx.isVAOptToken(Tokens[I + 1])) &&
372              "Token following # is not an argument or __VA_OPT__!");
373 
374       if (ArgNo == -1) {
375         // Handle the __VA_OPT__ case.
376         VCtx.sawHashOrHashAtBefore(NextTokGetsSpace,
377                                    CurTok.is(tok::hashat));
378         continue;
379       }
380       // Else handle the simple argument case.
381       SourceLocation ExpansionLocStart =
382           getExpansionLocForMacroDefLoc(CurTok.getLocation());
383       SourceLocation ExpansionLocEnd =
384           getExpansionLocForMacroDefLoc(Tokens[I+1].getLocation());
385 
386       bool Charify = CurTok.is(tok::hashat);
387       const Token *UnexpArg = ActualArgs->getUnexpArgument(ArgNo);
388       Token Res = MacroArgs::StringifyArgument(
389           UnexpArg, PP, Charify, ExpansionLocStart, ExpansionLocEnd);
390       Res.setFlag(Token::StringifiedInMacro);
391 
392       // The stringified/charified string leading space flag gets set to match
393       // the #/#@ operator.
394       if (NextTokGetsSpace)
395         Res.setFlag(Token::LeadingSpace);
396 
397       ResultToks.push_back(Res);
398       MadeChange = true;
399       ++I;  // Skip arg name.
400       NextTokGetsSpace = false;
401       continue;
402     }
403 
404     // Find out if there is a paste (##) operator before or after the token.
405     bool NonEmptyPasteBefore =
406       !ResultToks.empty() && ResultToks.back().is(tok::hashhash);
407     bool PasteBefore = I != 0 && Tokens[I-1].is(tok::hashhash);
408     bool PasteAfter = I+1 != E && Tokens[I+1].is(tok::hashhash);
409     bool RParenAfter = I+1 != E && Tokens[I+1].is(tok::r_paren);
410 
411     assert((!NonEmptyPasteBefore || PasteBefore || VCtx.isInVAOpt()) &&
412            "unexpected ## in ResultToks");
413 
414     // Otherwise, if this is not an argument token, just add the token to the
415     // output buffer.
416     IdentifierInfo *II = CurTok.getIdentifierInfo();
417     int ArgNo = II ? Macro->getParameterNum(II) : -1;
418     if (ArgNo == -1) {
419       // This isn't an argument, just add it.
420       ResultToks.push_back(CurTok);
421 
422       if (NextTokGetsSpace) {
423         ResultToks.back().setFlag(Token::LeadingSpace);
424         NextTokGetsSpace = false;
425       } else if (PasteBefore && !NonEmptyPasteBefore)
426         ResultToks.back().clearFlag(Token::LeadingSpace);
427 
428       continue;
429     }
430 
431     // An argument is expanded somehow, the result is different than the
432     // input.
433     MadeChange = true;
434 
435     // Otherwise, this is a use of the argument.
436 
437     // In Microsoft mode, remove the comma before __VA_ARGS__ to ensure there
438     // are no trailing commas if __VA_ARGS__ is empty.
439     if (!PasteBefore && ActualArgs->isVarargsElidedUse() &&
440         MaybeRemoveCommaBeforeVaArgs(ResultToks,
441                                      /*HasPasteOperator=*/false,
442                                      Macro, ArgNo, PP))
443       continue;
444 
445     // If it is not the LHS/RHS of a ## operator, we must pre-expand the
446     // argument and substitute the expanded tokens into the result.  This is
447     // C99 6.10.3.1p1.
448     if (!PasteBefore && !PasteAfter) {
449       const Token *ResultArgToks;
450 
451       // Only preexpand the argument if it could possibly need it.  This
452       // avoids some work in common cases.
453       const Token *ArgTok = ActualArgs->getUnexpArgument(ArgNo);
454       if (ActualArgs->ArgNeedsPreexpansion(ArgTok, PP))
455         ResultArgToks = &ActualArgs->getPreExpArgument(ArgNo, PP)[0];
456       else
457         ResultArgToks = ArgTok;  // Use non-preexpanded tokens.
458 
459       // If the arg token expanded into anything, append it.
460       if (ResultArgToks->isNot(tok::eof)) {
461         size_t FirstResult = ResultToks.size();
462         unsigned NumToks = MacroArgs::getArgLength(ResultArgToks);
463         ResultToks.append(ResultArgToks, ResultArgToks+NumToks);
464 
465         // In Microsoft-compatibility mode, we follow MSVC's preprocessing
466         // behavior by not considering single commas from nested macro
467         // expansions as argument separators. Set a flag on the token so we can
468         // test for this later when the macro expansion is processed.
469         if (PP.getLangOpts().MSVCCompat && NumToks == 1 &&
470             ResultToks.back().is(tok::comma))
471           ResultToks.back().setFlag(Token::IgnoredComma);
472 
473         // If the '##' came from expanding an argument, turn it into 'unknown'
474         // to avoid pasting.
475         for (Token &Tok : llvm::drop_begin(ResultToks, FirstResult))
476           if (Tok.is(tok::hashhash))
477             Tok.setKind(tok::unknown);
478 
479         if(ExpandLocStart.isValid()) {
480           updateLocForMacroArgTokens(CurTok.getLocation(),
481                                      ResultToks.begin()+FirstResult,
482                                      ResultToks.end());
483         }
484 
485         // If any tokens were substituted from the argument, the whitespace
486         // before the first token should match the whitespace of the arg
487         // identifier.
488         ResultToks[FirstResult].setFlagValue(Token::LeadingSpace,
489                                              NextTokGetsSpace);
490         ResultToks[FirstResult].setFlagValue(Token::StartOfLine, false);
491         NextTokGetsSpace = false;
492       } else {
493         // We're creating a placeholder token. Usually this doesn't matter,
494         // but it can affect paste behavior when at the start or end of a
495         // __VA_OPT__.
496         if (NonEmptyPasteBefore) {
497           // We're imagining a placeholder token is inserted here. If this is
498           // the first token in a __VA_OPT__ after a ##, delete the ##.
499           assert(VCtx.isInVAOpt() && "should only happen inside a __VA_OPT__");
500           VCtx.hasPlaceholderAfterHashhashAtStart();
501         }
502         if (RParenAfter)
503           VCtx.hasPlaceholderBeforeRParen();
504       }
505       continue;
506     }
507 
508     // Okay, we have a token that is either the LHS or RHS of a paste (##)
509     // argument.  It gets substituted as its non-pre-expanded tokens.
510     const Token *ArgToks = ActualArgs->getUnexpArgument(ArgNo);
511     unsigned NumToks = MacroArgs::getArgLength(ArgToks);
512     if (NumToks) {  // Not an empty argument?
513       bool VaArgsPseudoPaste = false;
514       // If this is the GNU ", ## __VA_ARGS__" extension, and we just learned
515       // that __VA_ARGS__ expands to multiple tokens, avoid a pasting error when
516       // the expander tries to paste ',' with the first token of the __VA_ARGS__
517       // expansion.
518       if (NonEmptyPasteBefore && ResultToks.size() >= 2 &&
519           ResultToks[ResultToks.size()-2].is(tok::comma) &&
520           (unsigned)ArgNo == Macro->getNumParams()-1 &&
521           Macro->isVariadic()) {
522         VaArgsPseudoPaste = true;
523         // Remove the paste operator, report use of the extension.
524         PP.Diag(ResultToks.pop_back_val().getLocation(), diag::ext_paste_comma);
525       }
526 
527       ResultToks.append(ArgToks, ArgToks+NumToks);
528 
529       // If the '##' came from expanding an argument, turn it into 'unknown'
530       // to avoid pasting.
531       for (Token &Tok : llvm::make_range(ResultToks.end() - NumToks,
532                                          ResultToks.end())) {
533         if (Tok.is(tok::hashhash))
534           Tok.setKind(tok::unknown);
535       }
536 
537       if (ExpandLocStart.isValid()) {
538         updateLocForMacroArgTokens(CurTok.getLocation(),
539                                    ResultToks.end()-NumToks, ResultToks.end());
540       }
541 
542       // Transfer the leading whitespace information from the token
543       // (the macro argument) onto the first token of the
544       // expansion. Note that we don't do this for the GNU
545       // pseudo-paste extension ", ## __VA_ARGS__".
546       if (!VaArgsPseudoPaste) {
547         ResultToks[ResultToks.size() - NumToks].setFlagValue(Token::StartOfLine,
548                                                              false);
549         ResultToks[ResultToks.size() - NumToks].setFlagValue(
550             Token::LeadingSpace, NextTokGetsSpace);
551       }
552 
553       NextTokGetsSpace = false;
554       continue;
555     }
556 
557     // If an empty argument is on the LHS or RHS of a paste, the standard (C99
558     // 6.10.3.3p2,3) calls for a bunch of placemarker stuff to occur.  We
559     // implement this by eating ## operators when a LHS or RHS expands to
560     // empty.
561     if (PasteAfter) {
562       // Discard the argument token and skip (don't copy to the expansion
563       // buffer) the paste operator after it.
564       ++I;
565       continue;
566     }
567 
568     if (RParenAfter)
569       VCtx.hasPlaceholderBeforeRParen();
570 
571     // If this is on the RHS of a paste operator, we've already copied the
572     // paste operator to the ResultToks list, unless the LHS was empty too.
573     // Remove it.
574     assert(PasteBefore);
575     if (NonEmptyPasteBefore) {
576       assert(ResultToks.back().is(tok::hashhash));
577       // Do not remove the paste operator if it is the one before __VA_OPT__
578       // (and we are still processing tokens within VA_OPT).  We handle the case
579       // of removing the paste operator if __VA_OPT__ reduces to the notional
580       // placemarker above when we encounter the closing paren of VA_OPT.
581       if (!VCtx.isInVAOpt() ||
582           ResultToks.size() > VCtx.getNumberOfTokensPriorToVAOpt())
583         ResultToks.pop_back();
584       else
585         VCtx.hasPlaceholderAfterHashhashAtStart();
586     }
587 
588     // If this is the __VA_ARGS__ token, and if the argument wasn't provided,
589     // and if the macro had at least one real argument, and if the token before
590     // the ## was a comma, remove the comma.  This is a GCC extension which is
591     // disabled when using -std=c99.
592     if (ActualArgs->isVarargsElidedUse())
593       MaybeRemoveCommaBeforeVaArgs(ResultToks,
594                                    /*HasPasteOperator=*/true,
595                                    Macro, ArgNo, PP);
596   }
597 
598   // If anything changed, install this as the new Tokens list.
599   if (MadeChange) {
600     assert(!OwnsTokens && "This would leak if we already own the token list");
601     // This is deleted in the dtor.
602     NumTokens = ResultToks.size();
603     // The tokens will be added to Preprocessor's cache and will be removed
604     // when this TokenLexer finishes lexing them.
605     Tokens = PP.cacheMacroExpandedTokens(this, ResultToks);
606 
607     // The preprocessor cache of macro expanded tokens owns these tokens,not us.
608     OwnsTokens = false;
609   }
610 }
611 
612 /// Checks if two tokens form wide string literal.
613 static bool isWideStringLiteralFromMacro(const Token &FirstTok,
614                                          const Token &SecondTok) {
615   return FirstTok.is(tok::identifier) &&
616          FirstTok.getIdentifierInfo()->isStr("L") && SecondTok.isLiteral() &&
617          SecondTok.stringifiedInMacro();
618 }
619 
620 /// Lex - Lex and return a token from this macro stream.
621 bool TokenLexer::Lex(Token &Tok) {
622   // Lexing off the end of the macro, pop this macro off the expansion stack.
623   if (isAtEnd()) {
624     // If this is a macro (not a token stream), mark the macro enabled now
625     // that it is no longer being expanded.
626     if (Macro) Macro->EnableMacro();
627 
628     Tok.startToken();
629     Tok.setFlagValue(Token::StartOfLine , AtStartOfLine);
630     Tok.setFlagValue(Token::LeadingSpace, HasLeadingSpace || NextTokGetsSpace);
631     if (CurTokenIdx == 0)
632       Tok.setFlag(Token::LeadingEmptyMacro);
633     return PP.HandleEndOfTokenLexer(Tok);
634   }
635 
636   SourceManager &SM = PP.getSourceManager();
637 
638   // If this is the first token of the expanded result, we inherit spacing
639   // properties later.
640   bool isFirstToken = CurTokenIdx == 0;
641 
642   // Get the next token to return.
643   Tok = Tokens[CurTokenIdx++];
644   if (IsReinject)
645     Tok.setFlag(Token::IsReinjected);
646 
647   bool TokenIsFromPaste = false;
648 
649   // If this token is followed by a token paste (##) operator, paste the tokens!
650   // Note that ## is a normal token when not expanding a macro.
651   if (!isAtEnd() && Macro &&
652       (Tokens[CurTokenIdx].is(tok::hashhash) ||
653        // Special processing of L#x macros in -fms-compatibility mode.
654        // Microsoft compiler is able to form a wide string literal from
655        // 'L#macro_arg' construct in a function-like macro.
656        (PP.getLangOpts().MSVCCompat &&
657         isWideStringLiteralFromMacro(Tok, Tokens[CurTokenIdx])))) {
658     // When handling the microsoft /##/ extension, the final token is
659     // returned by pasteTokens, not the pasted token.
660     if (pasteTokens(Tok))
661       return true;
662 
663     TokenIsFromPaste = true;
664   }
665 
666   // The token's current location indicate where the token was lexed from.  We
667   // need this information to compute the spelling of the token, but any
668   // diagnostics for the expanded token should appear as if they came from
669   // ExpansionLoc.  Pull this information together into a new SourceLocation
670   // that captures all of this.
671   if (ExpandLocStart.isValid() &&   // Don't do this for token streams.
672       // Check that the token's location was not already set properly.
673       SM.isBeforeInSLocAddrSpace(Tok.getLocation(), MacroStartSLocOffset)) {
674     SourceLocation instLoc;
675     if (Tok.is(tok::comment)) {
676       instLoc = SM.createExpansionLoc(Tok.getLocation(),
677                                       ExpandLocStart,
678                                       ExpandLocEnd,
679                                       Tok.getLength());
680     } else {
681       instLoc = getExpansionLocForMacroDefLoc(Tok.getLocation());
682     }
683 
684     Tok.setLocation(instLoc);
685   }
686 
687   // If this is the first token, set the lexical properties of the token to
688   // match the lexical properties of the macro identifier.
689   if (isFirstToken) {
690     Tok.setFlagValue(Token::StartOfLine , AtStartOfLine);
691     Tok.setFlagValue(Token::LeadingSpace, HasLeadingSpace);
692   } else {
693     // If this is not the first token, we may still need to pass through
694     // leading whitespace if we've expanded a macro.
695     if (AtStartOfLine) Tok.setFlag(Token::StartOfLine);
696     if (HasLeadingSpace) Tok.setFlag(Token::LeadingSpace);
697   }
698   AtStartOfLine = false;
699   HasLeadingSpace = false;
700 
701   // Handle recursive expansion!
702   if (!Tok.isAnnotation() && Tok.getIdentifierInfo() != nullptr) {
703     // Change the kind of this identifier to the appropriate token kind, e.g.
704     // turning "for" into a keyword.
705     IdentifierInfo *II = Tok.getIdentifierInfo();
706     Tok.setKind(II->getTokenID());
707 
708     // If this identifier was poisoned and from a paste, emit an error.  This
709     // won't be handled by Preprocessor::HandleIdentifier because this is coming
710     // from a macro expansion.
711     if (II->isPoisoned() && TokenIsFromPaste) {
712       PP.HandlePoisonedIdentifier(Tok);
713     }
714 
715     if (!DisableMacroExpansion && II->isHandleIdentifierCase())
716       return PP.HandleIdentifier(Tok);
717   }
718 
719   // Otherwise, return a normal token.
720   return true;
721 }
722 
723 bool TokenLexer::pasteTokens(Token &Tok) {
724   return pasteTokens(Tok, llvm::makeArrayRef(Tokens, NumTokens), CurTokenIdx);
725 }
726 
727 /// LHSTok is the LHS of a ## operator, and CurTokenIdx is the ##
728 /// operator.  Read the ## and RHS, and paste the LHS/RHS together.  If there
729 /// are more ## after it, chomp them iteratively.  Return the result as LHSTok.
730 /// If this returns true, the caller should immediately return the token.
731 bool TokenLexer::pasteTokens(Token &LHSTok, ArrayRef<Token> TokenStream,
732                              unsigned int &CurIdx) {
733   assert(CurIdx > 0 && "## can not be the first token within tokens");
734   assert((TokenStream[CurIdx].is(tok::hashhash) ||
735          (PP.getLangOpts().MSVCCompat &&
736           isWideStringLiteralFromMacro(LHSTok, TokenStream[CurIdx]))) &&
737              "Token at this Index must be ## or part of the MSVC 'L "
738              "#macro-arg' pasting pair");
739 
740   // MSVC: If previous token was pasted, this must be a recovery from an invalid
741   // paste operation. Ignore spaces before this token to mimic MSVC output.
742   // Required for generating valid UUID strings in some MS headers.
743   if (PP.getLangOpts().MicrosoftExt && (CurIdx >= 2) &&
744       TokenStream[CurIdx - 2].is(tok::hashhash))
745     LHSTok.clearFlag(Token::LeadingSpace);
746 
747   SmallString<128> Buffer;
748   const char *ResultTokStrPtr = nullptr;
749   SourceLocation StartLoc = LHSTok.getLocation();
750   SourceLocation PasteOpLoc;
751 
752   auto IsAtEnd = [&TokenStream, &CurIdx] {
753     return TokenStream.size() == CurIdx;
754   };
755 
756   do {
757     // Consume the ## operator if any.
758     PasteOpLoc = TokenStream[CurIdx].getLocation();
759     if (TokenStream[CurIdx].is(tok::hashhash))
760       ++CurIdx;
761     assert(!IsAtEnd() && "No token on the RHS of a paste operator!");
762 
763     // Get the RHS token.
764     const Token &RHS = TokenStream[CurIdx];
765 
766     // Allocate space for the result token.  This is guaranteed to be enough for
767     // the two tokens.
768     Buffer.resize(LHSTok.getLength() + RHS.getLength());
769 
770     // Get the spelling of the LHS token in Buffer.
771     const char *BufPtr = &Buffer[0];
772     bool Invalid = false;
773     unsigned LHSLen = PP.getSpelling(LHSTok, BufPtr, &Invalid);
774     if (BufPtr != &Buffer[0])   // Really, we want the chars in Buffer!
775       memcpy(&Buffer[0], BufPtr, LHSLen);
776     if (Invalid)
777       return true;
778 
779     BufPtr = Buffer.data() + LHSLen;
780     unsigned RHSLen = PP.getSpelling(RHS, BufPtr, &Invalid);
781     if (Invalid)
782       return true;
783     if (RHSLen && BufPtr != &Buffer[LHSLen])
784       // Really, we want the chars in Buffer!
785       memcpy(&Buffer[LHSLen], BufPtr, RHSLen);
786 
787     // Trim excess space.
788     Buffer.resize(LHSLen+RHSLen);
789 
790     // Plop the pasted result (including the trailing newline and null) into a
791     // scratch buffer where we can lex it.
792     Token ResultTokTmp;
793     ResultTokTmp.startToken();
794 
795     // Claim that the tmp token is a string_literal so that we can get the
796     // character pointer back from CreateString in getLiteralData().
797     ResultTokTmp.setKind(tok::string_literal);
798     PP.CreateString(Buffer, ResultTokTmp);
799     SourceLocation ResultTokLoc = ResultTokTmp.getLocation();
800     ResultTokStrPtr = ResultTokTmp.getLiteralData();
801 
802     // Lex the resultant pasted token into Result.
803     Token Result;
804 
805     if (LHSTok.isAnyIdentifier() && RHS.isAnyIdentifier()) {
806       // Common paste case: identifier+identifier = identifier.  Avoid creating
807       // a lexer and other overhead.
808       PP.IncrementPasteCounter(true);
809       Result.startToken();
810       Result.setKind(tok::raw_identifier);
811       Result.setRawIdentifierData(ResultTokStrPtr);
812       Result.setLocation(ResultTokLoc);
813       Result.setLength(LHSLen+RHSLen);
814     } else {
815       PP.IncrementPasteCounter(false);
816 
817       assert(ResultTokLoc.isFileID() &&
818              "Should be a raw location into scratch buffer");
819       SourceManager &SourceMgr = PP.getSourceManager();
820       FileID LocFileID = SourceMgr.getFileID(ResultTokLoc);
821 
822       bool Invalid = false;
823       const char *ScratchBufStart
824         = SourceMgr.getBufferData(LocFileID, &Invalid).data();
825       if (Invalid)
826         return false;
827 
828       // Make a lexer to lex this string from.  Lex just this one token.
829       // Make a lexer object so that we lex and expand the paste result.
830       Lexer TL(SourceMgr.getLocForStartOfFile(LocFileID),
831                PP.getLangOpts(), ScratchBufStart,
832                ResultTokStrPtr, ResultTokStrPtr+LHSLen+RHSLen);
833 
834       // Lex a token in raw mode.  This way it won't look up identifiers
835       // automatically, lexing off the end will return an eof token, and
836       // warnings are disabled.  This returns true if the result token is the
837       // entire buffer.
838       bool isInvalid = !TL.LexFromRawLexer(Result);
839 
840       // If we got an EOF token, we didn't form even ONE token.  For example, we
841       // did "/ ## /" to get "//".
842       isInvalid |= Result.is(tok::eof);
843 
844       // If pasting the two tokens didn't form a full new token, this is an
845       // error.  This occurs with "x ## +"  and other stuff.  Return with LHSTok
846       // unmodified and with RHS as the next token to lex.
847       if (isInvalid) {
848         // Explicitly convert the token location to have proper expansion
849         // information so that the user knows where it came from.
850         SourceManager &SM = PP.getSourceManager();
851         SourceLocation Loc =
852           SM.createExpansionLoc(PasteOpLoc, ExpandLocStart, ExpandLocEnd, 2);
853 
854         // Test for the Microsoft extension of /##/ turning into // here on the
855         // error path.
856         if (PP.getLangOpts().MicrosoftExt && LHSTok.is(tok::slash) &&
857             RHS.is(tok::slash)) {
858           HandleMicrosoftCommentPaste(LHSTok, Loc);
859           return true;
860         }
861 
862         // Do not emit the error when preprocessing assembler code.
863         if (!PP.getLangOpts().AsmPreprocessor) {
864           // If we're in microsoft extensions mode, downgrade this from a hard
865           // error to an extension that defaults to an error.  This allows
866           // disabling it.
867           PP.Diag(Loc, PP.getLangOpts().MicrosoftExt ? diag::ext_pp_bad_paste_ms
868                                                      : diag::err_pp_bad_paste)
869               << Buffer;
870         }
871 
872         // An error has occurred so exit loop.
873         break;
874       }
875 
876       // Turn ## into 'unknown' to avoid # ## # from looking like a paste
877       // operator.
878       if (Result.is(tok::hashhash))
879         Result.setKind(tok::unknown);
880     }
881 
882     // Transfer properties of the LHS over the Result.
883     Result.setFlagValue(Token::StartOfLine , LHSTok.isAtStartOfLine());
884     Result.setFlagValue(Token::LeadingSpace, LHSTok.hasLeadingSpace());
885 
886     // Finally, replace LHS with the result, consume the RHS, and iterate.
887     ++CurIdx;
888     LHSTok = Result;
889   } while (!IsAtEnd() && TokenStream[CurIdx].is(tok::hashhash));
890 
891   SourceLocation EndLoc = TokenStream[CurIdx - 1].getLocation();
892 
893   // The token's current location indicate where the token was lexed from.  We
894   // need this information to compute the spelling of the token, but any
895   // diagnostics for the expanded token should appear as if the token was
896   // expanded from the full ## expression. Pull this information together into
897   // a new SourceLocation that captures all of this.
898   SourceManager &SM = PP.getSourceManager();
899   if (StartLoc.isFileID())
900     StartLoc = getExpansionLocForMacroDefLoc(StartLoc);
901   if (EndLoc.isFileID())
902     EndLoc = getExpansionLocForMacroDefLoc(EndLoc);
903   FileID MacroFID = SM.getFileID(MacroExpansionStart);
904   while (SM.getFileID(StartLoc) != MacroFID)
905     StartLoc = SM.getImmediateExpansionRange(StartLoc).getBegin();
906   while (SM.getFileID(EndLoc) != MacroFID)
907     EndLoc = SM.getImmediateExpansionRange(EndLoc).getEnd();
908 
909   LHSTok.setLocation(SM.createExpansionLoc(LHSTok.getLocation(), StartLoc, EndLoc,
910                                         LHSTok.getLength()));
911 
912   // Now that we got the result token, it will be subject to expansion.  Since
913   // token pasting re-lexes the result token in raw mode, identifier information
914   // isn't looked up.  As such, if the result is an identifier, look up id info.
915   if (LHSTok.is(tok::raw_identifier)) {
916     // Look up the identifier info for the token.  We disabled identifier lookup
917     // by saying we're skipping contents, so we need to do this manually.
918     PP.LookUpIdentifierInfo(LHSTok);
919   }
920   return false;
921 }
922 
923 /// isNextTokenLParen - If the next token lexed will pop this macro off the
924 /// expansion stack, return 2.  If the next unexpanded token is a '(', return
925 /// 1, otherwise return 0.
926 unsigned TokenLexer::isNextTokenLParen() const {
927   // Out of tokens?
928   if (isAtEnd())
929     return 2;
930   return Tokens[CurTokenIdx].is(tok::l_paren);
931 }
932 
933 /// isParsingPreprocessorDirective - Return true if we are in the middle of a
934 /// preprocessor directive.
935 bool TokenLexer::isParsingPreprocessorDirective() const {
936   return Tokens[NumTokens-1].is(tok::eod) && !isAtEnd();
937 }
938 
939 /// HandleMicrosoftCommentPaste - In microsoft compatibility mode, /##/ pastes
940 /// together to form a comment that comments out everything in the current
941 /// macro, other active macros, and anything left on the current physical
942 /// source line of the expanded buffer.  Handle this by returning the
943 /// first token on the next line.
944 void TokenLexer::HandleMicrosoftCommentPaste(Token &Tok, SourceLocation OpLoc) {
945   PP.Diag(OpLoc, diag::ext_comment_paste_microsoft);
946 
947   // We 'comment out' the rest of this macro by just ignoring the rest of the
948   // tokens that have not been lexed yet, if any.
949 
950   // Since this must be a macro, mark the macro enabled now that it is no longer
951   // being expanded.
952   assert(Macro && "Token streams can't paste comments");
953   Macro->EnableMacro();
954 
955   PP.HandleMicrosoftCommentPaste(Tok);
956 }
957 
958 /// If \arg loc is a file ID and points inside the current macro
959 /// definition, returns the appropriate source location pointing at the
960 /// macro expansion source location entry, otherwise it returns an invalid
961 /// SourceLocation.
962 SourceLocation
963 TokenLexer::getExpansionLocForMacroDefLoc(SourceLocation loc) const {
964   assert(ExpandLocStart.isValid() && MacroExpansionStart.isValid() &&
965          "Not appropriate for token streams");
966   assert(loc.isValid() && loc.isFileID());
967 
968   SourceManager &SM = PP.getSourceManager();
969   assert(SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength) &&
970          "Expected loc to come from the macro definition");
971 
972   SourceLocation::UIntTy relativeOffset = 0;
973   SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength, &relativeOffset);
974   return MacroExpansionStart.getLocWithOffset(relativeOffset);
975 }
976 
977 /// Finds the tokens that are consecutive (from the same FileID)
978 /// creates a single SLocEntry, and assigns SourceLocations to each token that
979 /// point to that SLocEntry. e.g for
980 ///   assert(foo == bar);
981 /// There will be a single SLocEntry for the "foo == bar" chunk and locations
982 /// for the 'foo', '==', 'bar' tokens will point inside that chunk.
983 ///
984 /// \arg begin_tokens will be updated to a position past all the found
985 /// consecutive tokens.
986 static void updateConsecutiveMacroArgTokens(SourceManager &SM,
987                                             SourceLocation InstLoc,
988                                             Token *&begin_tokens,
989                                             Token * end_tokens) {
990   assert(begin_tokens < end_tokens);
991 
992   SourceLocation FirstLoc = begin_tokens->getLocation();
993   SourceLocation CurLoc = FirstLoc;
994 
995   // Compare the source location offset of tokens and group together tokens that
996   // are close, even if their locations point to different FileIDs. e.g.
997   //
998   //  |bar    |  foo | cake   |  (3 tokens from 3 consecutive FileIDs)
999   //  ^                    ^
1000   //  |bar       foo   cake|     (one SLocEntry chunk for all tokens)
1001   //
1002   // we can perform this "merge" since the token's spelling location depends
1003   // on the relative offset.
1004 
1005   Token *NextTok = begin_tokens + 1;
1006   for (; NextTok < end_tokens; ++NextTok) {
1007     SourceLocation NextLoc = NextTok->getLocation();
1008     if (CurLoc.isFileID() != NextLoc.isFileID())
1009       break; // Token from different kind of FileID.
1010 
1011     SourceLocation::IntTy RelOffs;
1012     if (!SM.isInSameSLocAddrSpace(CurLoc, NextLoc, &RelOffs))
1013       break; // Token from different local/loaded location.
1014     // Check that token is not before the previous token or more than 50
1015     // "characters" away.
1016     if (RelOffs < 0 || RelOffs > 50)
1017       break;
1018 
1019     if (CurLoc.isMacroID() && !SM.isWrittenInSameFile(CurLoc, NextLoc))
1020       break; // Token from a different macro.
1021 
1022     CurLoc = NextLoc;
1023   }
1024 
1025   // For the consecutive tokens, find the length of the SLocEntry to contain
1026   // all of them.
1027   Token &LastConsecutiveTok = *(NextTok-1);
1028   SourceLocation::IntTy LastRelOffs = 0;
1029   SM.isInSameSLocAddrSpace(FirstLoc, LastConsecutiveTok.getLocation(),
1030                            &LastRelOffs);
1031   SourceLocation::UIntTy FullLength =
1032       LastRelOffs + LastConsecutiveTok.getLength();
1033 
1034   // Create a macro expansion SLocEntry that will "contain" all of the tokens.
1035   SourceLocation Expansion =
1036       SM.createMacroArgExpansionLoc(FirstLoc, InstLoc,FullLength);
1037 
1038   // Change the location of the tokens from the spelling location to the new
1039   // expanded location.
1040   for (; begin_tokens < NextTok; ++begin_tokens) {
1041     Token &Tok = *begin_tokens;
1042     SourceLocation::IntTy RelOffs = 0;
1043     SM.isInSameSLocAddrSpace(FirstLoc, Tok.getLocation(), &RelOffs);
1044     Tok.setLocation(Expansion.getLocWithOffset(RelOffs));
1045   }
1046 }
1047 
1048 /// Creates SLocEntries and updates the locations of macro argument
1049 /// tokens to their new expanded locations.
1050 ///
1051 /// \param ArgIdSpellLoc the location of the macro argument id inside the macro
1052 /// definition.
1053 void TokenLexer::updateLocForMacroArgTokens(SourceLocation ArgIdSpellLoc,
1054                                             Token *begin_tokens,
1055                                             Token *end_tokens) {
1056   SourceManager &SM = PP.getSourceManager();
1057 
1058   SourceLocation InstLoc =
1059       getExpansionLocForMacroDefLoc(ArgIdSpellLoc);
1060 
1061   while (begin_tokens < end_tokens) {
1062     // If there's only one token just create a SLocEntry for it.
1063     if (end_tokens - begin_tokens == 1) {
1064       Token &Tok = *begin_tokens;
1065       Tok.setLocation(SM.createMacroArgExpansionLoc(Tok.getLocation(),
1066                                                     InstLoc,
1067                                                     Tok.getLength()));
1068       return;
1069     }
1070 
1071     updateConsecutiveMacroArgTokens(SM, InstLoc, begin_tokens, end_tokens);
1072   }
1073 }
1074 
1075 void TokenLexer::PropagateLineStartLeadingSpaceInfo(Token &Result) {
1076   AtStartOfLine = Result.isAtStartOfLine();
1077   HasLeadingSpace = Result.hasLeadingSpace();
1078 }
1079