1 //===--- PPDirectives.cpp - Directive Handling for Preprocessor -----------===//
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 /// \file
11 /// \brief Implements # directive processing for the Preprocessor.
12 ///
13 //===----------------------------------------------------------------------===//
14
15 #include "clang/Lex/Preprocessor.h"
16 #include "clang/Lex/LiteralSupport.h"
17 #include "clang/Lex/HeaderSearch.h"
18 #include "clang/Lex/MacroInfo.h"
19 #include "clang/Lex/LexDiagnostic.h"
20 #include "clang/Lex/CodeCompletionHandler.h"
21 #include "clang/Lex/ModuleLoader.h"
22 #include "clang/Lex/Pragma.h"
23 #include "clang/Basic/FileManager.h"
24 #include "clang/Basic/SourceManager.h"
25 #include "llvm/ADT/APInt.h"
26 #include "llvm/Support/ErrorHandling.h"
27 using namespace clang;
28
29 //===----------------------------------------------------------------------===//
30 // Utility Methods for Preprocessor Directive Handling.
31 //===----------------------------------------------------------------------===//
32
AllocateMacroInfo()33 MacroInfo *Preprocessor::AllocateMacroInfo() {
34 MacroInfoChain *MIChain;
35
36 if (MICache) {
37 MIChain = MICache;
38 MICache = MICache->Next;
39 }
40 else {
41 MIChain = BP.Allocate<MacroInfoChain>();
42 }
43
44 MIChain->Next = MIChainHead;
45 MIChain->Prev = 0;
46 if (MIChainHead)
47 MIChainHead->Prev = MIChain;
48 MIChainHead = MIChain;
49
50 return &(MIChain->MI);
51 }
52
AllocateMacroInfo(SourceLocation L)53 MacroInfo *Preprocessor::AllocateMacroInfo(SourceLocation L) {
54 MacroInfo *MI = AllocateMacroInfo();
55 new (MI) MacroInfo(L);
56 return MI;
57 }
58
CloneMacroInfo(const MacroInfo & MacroToClone)59 MacroInfo *Preprocessor::CloneMacroInfo(const MacroInfo &MacroToClone) {
60 MacroInfo *MI = AllocateMacroInfo();
61 new (MI) MacroInfo(MacroToClone, BP);
62 return MI;
63 }
64
65 /// \brief Release the specified MacroInfo to be reused for allocating
66 /// new MacroInfo objects.
ReleaseMacroInfo(MacroInfo * MI)67 void Preprocessor::ReleaseMacroInfo(MacroInfo *MI) {
68 MacroInfoChain *MIChain = (MacroInfoChain*) MI;
69 if (MacroInfoChain *Prev = MIChain->Prev) {
70 MacroInfoChain *Next = MIChain->Next;
71 Prev->Next = Next;
72 if (Next)
73 Next->Prev = Prev;
74 }
75 else {
76 assert(MIChainHead == MIChain);
77 MIChainHead = MIChain->Next;
78 MIChainHead->Prev = 0;
79 }
80 MIChain->Next = MICache;
81 MICache = MIChain;
82
83 MI->Destroy();
84 }
85
86 /// \brief Read and discard all tokens remaining on the current line until
87 /// the tok::eod token is found.
DiscardUntilEndOfDirective()88 void Preprocessor::DiscardUntilEndOfDirective() {
89 Token Tmp;
90 do {
91 LexUnexpandedToken(Tmp);
92 assert(Tmp.isNot(tok::eof) && "EOF seen while discarding directive tokens");
93 } while (Tmp.isNot(tok::eod));
94 }
95
96 /// \brief Lex and validate a macro name, which occurs after a
97 /// \#define or \#undef.
98 ///
99 /// This sets the token kind to eod and discards the rest
100 /// of the macro line if the macro name is invalid. \p isDefineUndef is 1 if
101 /// this is due to a a \#define, 2 if \#undef directive, 0 if it is something
102 /// else (e.g. \#ifdef).
ReadMacroName(Token & MacroNameTok,char isDefineUndef)103 void Preprocessor::ReadMacroName(Token &MacroNameTok, char isDefineUndef) {
104 // Read the token, don't allow macro expansion on it.
105 LexUnexpandedToken(MacroNameTok);
106
107 if (MacroNameTok.is(tok::code_completion)) {
108 if (CodeComplete)
109 CodeComplete->CodeCompleteMacroName(isDefineUndef == 1);
110 setCodeCompletionReached();
111 LexUnexpandedToken(MacroNameTok);
112 }
113
114 // Missing macro name?
115 if (MacroNameTok.is(tok::eod)) {
116 Diag(MacroNameTok, diag::err_pp_missing_macro_name);
117 return;
118 }
119
120 IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
121 if (II == 0) {
122 bool Invalid = false;
123 std::string Spelling = getSpelling(MacroNameTok, &Invalid);
124 if (Invalid)
125 return;
126
127 const IdentifierInfo &Info = Identifiers.get(Spelling);
128
129 // Allow #defining |and| and friends in microsoft mode.
130 if (Info.isCPlusPlusOperatorKeyword() && getLangOpts().MicrosoftMode) {
131 MacroNameTok.setIdentifierInfo(getIdentifierInfo(Spelling));
132 return;
133 }
134
135 if (Info.isCPlusPlusOperatorKeyword())
136 // C++ 2.5p2: Alternative tokens behave the same as its primary token
137 // except for their spellings.
138 Diag(MacroNameTok, diag::err_pp_operator_used_as_macro_name) << Spelling;
139 else
140 Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
141 // Fall through on error.
142 } else if (isDefineUndef && II->getPPKeywordID() == tok::pp_defined) {
143 // Error if defining "defined": C99 6.10.8.4.
144 Diag(MacroNameTok, diag::err_defined_macro_name);
145 } else if (isDefineUndef && II->hasMacroDefinition() &&
146 getMacroInfo(II)->isBuiltinMacro()) {
147 // Error if defining "__LINE__" and other builtins: C99 6.10.8.4.
148 if (isDefineUndef == 1)
149 Diag(MacroNameTok, diag::pp_redef_builtin_macro);
150 else
151 Diag(MacroNameTok, diag::pp_undef_builtin_macro);
152 } else {
153 // Okay, we got a good identifier node. Return it.
154 return;
155 }
156
157 // Invalid macro name, read and discard the rest of the line. Then set the
158 // token kind to tok::eod.
159 MacroNameTok.setKind(tok::eod);
160 return DiscardUntilEndOfDirective();
161 }
162
163 /// \brief Ensure that the next token is a tok::eod token.
164 ///
165 /// If not, emit a diagnostic and consume up until the eod. If EnableMacros is
166 /// true, then we consider macros that expand to zero tokens as being ok.
CheckEndOfDirective(const char * DirType,bool EnableMacros)167 void Preprocessor::CheckEndOfDirective(const char *DirType, bool EnableMacros) {
168 Token Tmp;
169 // Lex unexpanded tokens for most directives: macros might expand to zero
170 // tokens, causing us to miss diagnosing invalid lines. Some directives (like
171 // #line) allow empty macros.
172 if (EnableMacros)
173 Lex(Tmp);
174 else
175 LexUnexpandedToken(Tmp);
176
177 // There should be no tokens after the directive, but we allow them as an
178 // extension.
179 while (Tmp.is(tok::comment)) // Skip comments in -C mode.
180 LexUnexpandedToken(Tmp);
181
182 if (Tmp.isNot(tok::eod)) {
183 // Add a fixit in GNU/C99/C++ mode. Don't offer a fixit for strict-C89,
184 // or if this is a macro-style preprocessing directive, because it is more
185 // trouble than it is worth to insert /**/ and check that there is no /**/
186 // in the range also.
187 FixItHint Hint;
188 if ((LangOpts.GNUMode || LangOpts.C99 || LangOpts.CPlusPlus) &&
189 !CurTokenLexer)
190 Hint = FixItHint::CreateInsertion(Tmp.getLocation(),"//");
191 Diag(Tmp, diag::ext_pp_extra_tokens_at_eol) << DirType << Hint;
192 DiscardUntilEndOfDirective();
193 }
194 }
195
196
197
198 /// SkipExcludedConditionalBlock - We just read a \#if or related directive and
199 /// decided that the subsequent tokens are in the \#if'd out portion of the
200 /// file. Lex the rest of the file, until we see an \#endif. If
201 /// FoundNonSkipPortion is true, then we have already emitted code for part of
202 /// this \#if directive, so \#else/\#elif blocks should never be entered.
203 /// If ElseOk is true, then \#else directives are ok, if not, then we have
204 /// already seen one so a \#else directive is a duplicate. When this returns,
205 /// the caller can lex the first valid token.
SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,bool FoundNonSkipPortion,bool FoundElse,SourceLocation ElseLoc)206 void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
207 bool FoundNonSkipPortion,
208 bool FoundElse,
209 SourceLocation ElseLoc) {
210 ++NumSkipped;
211 assert(CurTokenLexer == 0 && CurPPLexer && "Lexing a macro, not a file?");
212
213 CurPPLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false,
214 FoundNonSkipPortion, FoundElse);
215
216 if (CurPTHLexer) {
217 PTHSkipExcludedConditionalBlock();
218 return;
219 }
220
221 // Enter raw mode to disable identifier lookup (and thus macro expansion),
222 // disabling warnings, etc.
223 CurPPLexer->LexingRawMode = true;
224 Token Tok;
225 while (1) {
226 CurLexer->Lex(Tok);
227
228 if (Tok.is(tok::code_completion)) {
229 if (CodeComplete)
230 CodeComplete->CodeCompleteInConditionalExclusion();
231 setCodeCompletionReached();
232 continue;
233 }
234
235 // If this is the end of the buffer, we have an error.
236 if (Tok.is(tok::eof)) {
237 // Emit errors for each unterminated conditional on the stack, including
238 // the current one.
239 while (!CurPPLexer->ConditionalStack.empty()) {
240 if (CurLexer->getFileLoc() != CodeCompletionFileLoc)
241 Diag(CurPPLexer->ConditionalStack.back().IfLoc,
242 diag::err_pp_unterminated_conditional);
243 CurPPLexer->ConditionalStack.pop_back();
244 }
245
246 // Just return and let the caller lex after this #include.
247 break;
248 }
249
250 // If this token is not a preprocessor directive, just skip it.
251 if (Tok.isNot(tok::hash) || !Tok.isAtStartOfLine())
252 continue;
253
254 // We just parsed a # character at the start of a line, so we're in
255 // directive mode. Tell the lexer this so any newlines we see will be
256 // converted into an EOD token (this terminates the macro).
257 CurPPLexer->ParsingPreprocessorDirective = true;
258 if (CurLexer) CurLexer->SetCommentRetentionState(false);
259
260
261 // Read the next token, the directive flavor.
262 LexUnexpandedToken(Tok);
263
264 // If this isn't an identifier directive (e.g. is "# 1\n" or "#\n", or
265 // something bogus), skip it.
266 if (Tok.isNot(tok::raw_identifier)) {
267 CurPPLexer->ParsingPreprocessorDirective = false;
268 // Restore comment saving mode.
269 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments);
270 continue;
271 }
272
273 // If the first letter isn't i or e, it isn't intesting to us. We know that
274 // this is safe in the face of spelling differences, because there is no way
275 // to spell an i/e in a strange way that is another letter. Skipping this
276 // allows us to avoid looking up the identifier info for #define/#undef and
277 // other common directives.
278 const char *RawCharData = Tok.getRawIdentifierData();
279
280 char FirstChar = RawCharData[0];
281 if (FirstChar >= 'a' && FirstChar <= 'z' &&
282 FirstChar != 'i' && FirstChar != 'e') {
283 CurPPLexer->ParsingPreprocessorDirective = false;
284 // Restore comment saving mode.
285 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments);
286 continue;
287 }
288
289 // Get the identifier name without trigraphs or embedded newlines. Note
290 // that we can't use Tok.getIdentifierInfo() because its lookup is disabled
291 // when skipping.
292 char DirectiveBuf[20];
293 StringRef Directive;
294 if (!Tok.needsCleaning() && Tok.getLength() < 20) {
295 Directive = StringRef(RawCharData, Tok.getLength());
296 } else {
297 std::string DirectiveStr = getSpelling(Tok);
298 unsigned IdLen = DirectiveStr.size();
299 if (IdLen >= 20) {
300 CurPPLexer->ParsingPreprocessorDirective = false;
301 // Restore comment saving mode.
302 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments);
303 continue;
304 }
305 memcpy(DirectiveBuf, &DirectiveStr[0], IdLen);
306 Directive = StringRef(DirectiveBuf, IdLen);
307 }
308
309 if (Directive.startswith("if")) {
310 StringRef Sub = Directive.substr(2);
311 if (Sub.empty() || // "if"
312 Sub == "def" || // "ifdef"
313 Sub == "ndef") { // "ifndef"
314 // We know the entire #if/#ifdef/#ifndef block will be skipped, don't
315 // bother parsing the condition.
316 DiscardUntilEndOfDirective();
317 CurPPLexer->pushConditionalLevel(Tok.getLocation(), /*wasskipping*/true,
318 /*foundnonskip*/false,
319 /*foundelse*/false);
320 }
321 } else if (Directive[0] == 'e') {
322 StringRef Sub = Directive.substr(1);
323 if (Sub == "ndif") { // "endif"
324 PPConditionalInfo CondInfo;
325 CondInfo.WasSkipping = true; // Silence bogus warning.
326 bool InCond = CurPPLexer->popConditionalLevel(CondInfo);
327 (void)InCond; // Silence warning in no-asserts mode.
328 assert(!InCond && "Can't be skipping if not in a conditional!");
329
330 // If we popped the outermost skipping block, we're done skipping!
331 if (!CondInfo.WasSkipping) {
332 // Restore the value of LexingRawMode so that trailing comments
333 // are handled correctly, if we've reached the outermost block.
334 CurPPLexer->LexingRawMode = false;
335 CheckEndOfDirective("endif");
336 CurPPLexer->LexingRawMode = true;
337 if (Callbacks)
338 Callbacks->Endif(Tok.getLocation(), CondInfo.IfLoc);
339 break;
340 } else {
341 DiscardUntilEndOfDirective();
342 }
343 } else if (Sub == "lse") { // "else".
344 // #else directive in a skipping conditional. If not in some other
345 // skipping conditional, and if #else hasn't already been seen, enter it
346 // as a non-skipping conditional.
347 PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel();
348
349 // If this is a #else with a #else before it, report the error.
350 if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_else_after_else);
351
352 // Note that we've seen a #else in this conditional.
353 CondInfo.FoundElse = true;
354
355 // If the conditional is at the top level, and the #if block wasn't
356 // entered, enter the #else block now.
357 if (!CondInfo.WasSkipping && !CondInfo.FoundNonSkip) {
358 CondInfo.FoundNonSkip = true;
359 // Restore the value of LexingRawMode so that trailing comments
360 // are handled correctly.
361 CurPPLexer->LexingRawMode = false;
362 CheckEndOfDirective("else");
363 CurPPLexer->LexingRawMode = true;
364 if (Callbacks)
365 Callbacks->Else(Tok.getLocation(), CondInfo.IfLoc);
366 break;
367 } else {
368 DiscardUntilEndOfDirective(); // C99 6.10p4.
369 }
370 } else if (Sub == "lif") { // "elif".
371 PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel();
372
373 bool ShouldEnter;
374 const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation();
375 // If this is in a skipping block or if we're already handled this #if
376 // block, don't bother parsing the condition.
377 if (CondInfo.WasSkipping || CondInfo.FoundNonSkip) {
378 DiscardUntilEndOfDirective();
379 ShouldEnter = false;
380 } else {
381 // Restore the value of LexingRawMode so that identifiers are
382 // looked up, etc, inside the #elif expression.
383 assert(CurPPLexer->LexingRawMode && "We have to be skipping here!");
384 CurPPLexer->LexingRawMode = false;
385 IdentifierInfo *IfNDefMacro = 0;
386 ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro);
387 CurPPLexer->LexingRawMode = true;
388 }
389 const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation();
390
391 // If this is a #elif with a #else before it, report the error.
392 if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_elif_after_else);
393
394 // If this condition is true, enter it!
395 if (ShouldEnter) {
396 CondInfo.FoundNonSkip = true;
397 if (Callbacks)
398 Callbacks->Elif(Tok.getLocation(),
399 SourceRange(ConditionalBegin, ConditionalEnd),
400 CondInfo.IfLoc);
401 break;
402 }
403 }
404 }
405
406 CurPPLexer->ParsingPreprocessorDirective = false;
407 // Restore comment saving mode.
408 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments);
409 }
410
411 // Finally, if we are out of the conditional (saw an #endif or ran off the end
412 // of the file, just stop skipping and return to lexing whatever came after
413 // the #if block.
414 CurPPLexer->LexingRawMode = false;
415
416 if (Callbacks) {
417 SourceLocation BeginLoc = ElseLoc.isValid() ? ElseLoc : IfTokenLoc;
418 Callbacks->SourceRangeSkipped(SourceRange(BeginLoc, Tok.getLocation()));
419 }
420 }
421
PTHSkipExcludedConditionalBlock()422 void Preprocessor::PTHSkipExcludedConditionalBlock() {
423
424 while (1) {
425 assert(CurPTHLexer);
426 assert(CurPTHLexer->LexingRawMode == false);
427
428 // Skip to the next '#else', '#elif', or #endif.
429 if (CurPTHLexer->SkipBlock()) {
430 // We have reached an #endif. Both the '#' and 'endif' tokens
431 // have been consumed by the PTHLexer. Just pop off the condition level.
432 PPConditionalInfo CondInfo;
433 bool InCond = CurPTHLexer->popConditionalLevel(CondInfo);
434 (void)InCond; // Silence warning in no-asserts mode.
435 assert(!InCond && "Can't be skipping if not in a conditional!");
436 break;
437 }
438
439 // We have reached a '#else' or '#elif'. Lex the next token to get
440 // the directive flavor.
441 Token Tok;
442 LexUnexpandedToken(Tok);
443
444 // We can actually look up the IdentifierInfo here since we aren't in
445 // raw mode.
446 tok::PPKeywordKind K = Tok.getIdentifierInfo()->getPPKeywordID();
447
448 if (K == tok::pp_else) {
449 // #else: Enter the else condition. We aren't in a nested condition
450 // since we skip those. We're always in the one matching the last
451 // blocked we skipped.
452 PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel();
453 // Note that we've seen a #else in this conditional.
454 CondInfo.FoundElse = true;
455
456 // If the #if block wasn't entered then enter the #else block now.
457 if (!CondInfo.FoundNonSkip) {
458 CondInfo.FoundNonSkip = true;
459
460 // Scan until the eod token.
461 CurPTHLexer->ParsingPreprocessorDirective = true;
462 DiscardUntilEndOfDirective();
463 CurPTHLexer->ParsingPreprocessorDirective = false;
464
465 break;
466 }
467
468 // Otherwise skip this block.
469 continue;
470 }
471
472 assert(K == tok::pp_elif);
473 PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel();
474
475 // If this is a #elif with a #else before it, report the error.
476 if (CondInfo.FoundElse)
477 Diag(Tok, diag::pp_err_elif_after_else);
478
479 // If this is in a skipping block or if we're already handled this #if
480 // block, don't bother parsing the condition. We just skip this block.
481 if (CondInfo.FoundNonSkip)
482 continue;
483
484 // Evaluate the condition of the #elif.
485 IdentifierInfo *IfNDefMacro = 0;
486 CurPTHLexer->ParsingPreprocessorDirective = true;
487 bool ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro);
488 CurPTHLexer->ParsingPreprocessorDirective = false;
489
490 // If this condition is true, enter it!
491 if (ShouldEnter) {
492 CondInfo.FoundNonSkip = true;
493 break;
494 }
495
496 // Otherwise, skip this block and go to the next one.
497 continue;
498 }
499 }
500
LookupFile(StringRef Filename,bool isAngled,const DirectoryLookup * FromDir,const DirectoryLookup * & CurDir,SmallVectorImpl<char> * SearchPath,SmallVectorImpl<char> * RelativePath,Module ** SuggestedModule,bool SkipCache)501 const FileEntry *Preprocessor::LookupFile(
502 StringRef Filename,
503 bool isAngled,
504 const DirectoryLookup *FromDir,
505 const DirectoryLookup *&CurDir,
506 SmallVectorImpl<char> *SearchPath,
507 SmallVectorImpl<char> *RelativePath,
508 Module **SuggestedModule,
509 bool SkipCache) {
510 // If the header lookup mechanism may be relative to the current file, pass in
511 // info about where the current file is.
512 const FileEntry *CurFileEnt = 0;
513 if (!FromDir) {
514 FileID FID = getCurrentFileLexer()->getFileID();
515 CurFileEnt = SourceMgr.getFileEntryForID(FID);
516
517 // If there is no file entry associated with this file, it must be the
518 // predefines buffer. Any other file is not lexed with a normal lexer, so
519 // it won't be scanned for preprocessor directives. If we have the
520 // predefines buffer, resolve #include references (which come from the
521 // -include command line argument) as if they came from the main file, this
522 // affects file lookup etc.
523 if (CurFileEnt == 0) {
524 FID = SourceMgr.getMainFileID();
525 CurFileEnt = SourceMgr.getFileEntryForID(FID);
526 }
527 }
528
529 // Do a standard file entry lookup.
530 CurDir = CurDirLookup;
531 const FileEntry *FE = HeaderInfo.LookupFile(
532 Filename, isAngled, FromDir, CurDir, CurFileEnt,
533 SearchPath, RelativePath, SuggestedModule, SkipCache);
534 if (FE) return FE;
535
536 // Otherwise, see if this is a subframework header. If so, this is relative
537 // to one of the headers on the #include stack. Walk the list of the current
538 // headers on the #include stack and pass them to HeaderInfo.
539 // FIXME: SuggestedModule!
540 if (IsFileLexer()) {
541 if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID())))
542 if ((FE = HeaderInfo.LookupSubframeworkHeader(Filename, CurFileEnt,
543 SearchPath, RelativePath)))
544 return FE;
545 }
546
547 for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) {
548 IncludeStackInfo &ISEntry = IncludeMacroStack[e-i-1];
549 if (IsFileLexer(ISEntry)) {
550 if ((CurFileEnt =
551 SourceMgr.getFileEntryForID(ISEntry.ThePPLexer->getFileID())))
552 if ((FE = HeaderInfo.LookupSubframeworkHeader(
553 Filename, CurFileEnt, SearchPath, RelativePath)))
554 return FE;
555 }
556 }
557
558 // Otherwise, we really couldn't find the file.
559 return 0;
560 }
561
562
563 //===----------------------------------------------------------------------===//
564 // Preprocessor Directive Handling.
565 //===----------------------------------------------------------------------===//
566
567 class Preprocessor::ResetMacroExpansionHelper {
568 public:
ResetMacroExpansionHelper(Preprocessor * pp)569 ResetMacroExpansionHelper(Preprocessor *pp)
570 : PP(pp), save(pp->DisableMacroExpansion) {
571 if (pp->MacroExpansionInDirectivesOverride)
572 pp->DisableMacroExpansion = false;
573 }
~ResetMacroExpansionHelper()574 ~ResetMacroExpansionHelper() {
575 PP->DisableMacroExpansion = save;
576 }
577 private:
578 Preprocessor *PP;
579 bool save;
580 };
581
582 /// HandleDirective - This callback is invoked when the lexer sees a # token
583 /// at the start of a line. This consumes the directive, modifies the
584 /// lexer/preprocessor state, and advances the lexer(s) so that the next token
585 /// read is the correct one.
HandleDirective(Token & Result)586 void Preprocessor::HandleDirective(Token &Result) {
587 // FIXME: Traditional: # with whitespace before it not recognized by K&R?
588
589 // We just parsed a # character at the start of a line, so we're in directive
590 // mode. Tell the lexer this so any newlines we see will be converted into an
591 // EOD token (which terminates the directive).
592 CurPPLexer->ParsingPreprocessorDirective = true;
593
594 ++NumDirectives;
595
596 // We are about to read a token. For the multiple-include optimization FA to
597 // work, we have to remember if we had read any tokens *before* this
598 // pp-directive.
599 bool ReadAnyTokensBeforeDirective =CurPPLexer->MIOpt.getHasReadAnyTokensVal();
600
601 // Save the '#' token in case we need to return it later.
602 Token SavedHash = Result;
603
604 // Read the next token, the directive flavor. This isn't expanded due to
605 // C99 6.10.3p8.
606 LexUnexpandedToken(Result);
607
608 // C99 6.10.3p11: Is this preprocessor directive in macro invocation? e.g.:
609 // #define A(x) #x
610 // A(abc
611 // #warning blah
612 // def)
613 // If so, the user is relying on undefined behavior, emit a diagnostic. Do
614 // not support this for #include-like directives, since that can result in
615 // terrible diagnostics, and does not work in GCC.
616 if (InMacroArgs) {
617 if (IdentifierInfo *II = Result.getIdentifierInfo()) {
618 switch (II->getPPKeywordID()) {
619 case tok::pp_include:
620 case tok::pp_import:
621 case tok::pp_include_next:
622 case tok::pp___include_macros:
623 Diag(Result, diag::err_embedded_include) << II->getName();
624 DiscardUntilEndOfDirective();
625 return;
626 default:
627 break;
628 }
629 }
630 Diag(Result, diag::ext_embedded_directive);
631 }
632
633 // Temporarily enable macro expansion if set so
634 // and reset to previous state when returning from this function.
635 ResetMacroExpansionHelper helper(this);
636
637 TryAgain:
638 switch (Result.getKind()) {
639 case tok::eod:
640 return; // null directive.
641 case tok::comment:
642 // Handle stuff like "# /*foo*/ define X" in -E -C mode.
643 LexUnexpandedToken(Result);
644 goto TryAgain;
645 case tok::code_completion:
646 if (CodeComplete)
647 CodeComplete->CodeCompleteDirective(
648 CurPPLexer->getConditionalStackDepth() > 0);
649 setCodeCompletionReached();
650 return;
651 case tok::numeric_constant: // # 7 GNU line marker directive.
652 if (getLangOpts().AsmPreprocessor)
653 break; // # 4 is not a preprocessor directive in .S files.
654 return HandleDigitDirective(Result);
655 default:
656 IdentifierInfo *II = Result.getIdentifierInfo();
657 if (II == 0) break; // Not an identifier.
658
659 // Ask what the preprocessor keyword ID is.
660 switch (II->getPPKeywordID()) {
661 default: break;
662 // C99 6.10.1 - Conditional Inclusion.
663 case tok::pp_if:
664 return HandleIfDirective(Result, ReadAnyTokensBeforeDirective);
665 case tok::pp_ifdef:
666 return HandleIfdefDirective(Result, false, true/*not valid for miopt*/);
667 case tok::pp_ifndef:
668 return HandleIfdefDirective(Result, true, ReadAnyTokensBeforeDirective);
669 case tok::pp_elif:
670 return HandleElifDirective(Result);
671 case tok::pp_else:
672 return HandleElseDirective(Result);
673 case tok::pp_endif:
674 return HandleEndifDirective(Result);
675
676 // C99 6.10.2 - Source File Inclusion.
677 case tok::pp_include:
678 // Handle #include.
679 return HandleIncludeDirective(SavedHash.getLocation(), Result);
680 case tok::pp___include_macros:
681 // Handle -imacros.
682 return HandleIncludeMacrosDirective(SavedHash.getLocation(), Result);
683
684 // C99 6.10.3 - Macro Replacement.
685 case tok::pp_define:
686 return HandleDefineDirective(Result);
687 case tok::pp_undef:
688 return HandleUndefDirective(Result);
689
690 // C99 6.10.4 - Line Control.
691 case tok::pp_line:
692 return HandleLineDirective(Result);
693
694 // C99 6.10.5 - Error Directive.
695 case tok::pp_error:
696 return HandleUserDiagnosticDirective(Result, false);
697
698 // C99 6.10.6 - Pragma Directive.
699 case tok::pp_pragma:
700 return HandlePragmaDirective(PIK_HashPragma);
701
702 // GNU Extensions.
703 case tok::pp_import:
704 return HandleImportDirective(SavedHash.getLocation(), Result);
705 case tok::pp_include_next:
706 return HandleIncludeNextDirective(SavedHash.getLocation(), Result);
707
708 case tok::pp_warning:
709 Diag(Result, diag::ext_pp_warning_directive);
710 return HandleUserDiagnosticDirective(Result, true);
711 case tok::pp_ident:
712 return HandleIdentSCCSDirective(Result);
713 case tok::pp_sccs:
714 return HandleIdentSCCSDirective(Result);
715 case tok::pp_assert:
716 //isExtension = true; // FIXME: implement #assert
717 break;
718 case tok::pp_unassert:
719 //isExtension = true; // FIXME: implement #unassert
720 break;
721
722 case tok::pp___public_macro:
723 if (getLangOpts().Modules)
724 return HandleMacroPublicDirective(Result);
725 break;
726
727 case tok::pp___private_macro:
728 if (getLangOpts().Modules)
729 return HandleMacroPrivateDirective(Result);
730 break;
731 }
732 break;
733 }
734
735 // If this is a .S file, treat unknown # directives as non-preprocessor
736 // directives. This is important because # may be a comment or introduce
737 // various pseudo-ops. Just return the # token and push back the following
738 // token to be lexed next time.
739 if (getLangOpts().AsmPreprocessor) {
740 Token *Toks = new Token[2];
741 // Return the # and the token after it.
742 Toks[0] = SavedHash;
743 Toks[1] = Result;
744
745 // If the second token is a hashhash token, then we need to translate it to
746 // unknown so the token lexer doesn't try to perform token pasting.
747 if (Result.is(tok::hashhash))
748 Toks[1].setKind(tok::unknown);
749
750 // Enter this token stream so that we re-lex the tokens. Make sure to
751 // enable macro expansion, in case the token after the # is an identifier
752 // that is expanded.
753 EnterTokenStream(Toks, 2, false, true);
754 return;
755 }
756
757 // If we reached here, the preprocessing token is not valid!
758 Diag(Result, diag::err_pp_invalid_directive);
759
760 // Read the rest of the PP line.
761 DiscardUntilEndOfDirective();
762
763 // Okay, we're done parsing the directive.
764 }
765
766 /// GetLineValue - Convert a numeric token into an unsigned value, emitting
767 /// Diagnostic DiagID if it is invalid, and returning the value in Val.
GetLineValue(Token & DigitTok,unsigned & Val,unsigned DiagID,Preprocessor & PP)768 static bool GetLineValue(Token &DigitTok, unsigned &Val,
769 unsigned DiagID, Preprocessor &PP) {
770 if (DigitTok.isNot(tok::numeric_constant)) {
771 PP.Diag(DigitTok, DiagID);
772
773 if (DigitTok.isNot(tok::eod))
774 PP.DiscardUntilEndOfDirective();
775 return true;
776 }
777
778 SmallString<64> IntegerBuffer;
779 IntegerBuffer.resize(DigitTok.getLength());
780 const char *DigitTokBegin = &IntegerBuffer[0];
781 bool Invalid = false;
782 unsigned ActualLength = PP.getSpelling(DigitTok, DigitTokBegin, &Invalid);
783 if (Invalid)
784 return true;
785
786 // Verify that we have a simple digit-sequence, and compute the value. This
787 // is always a simple digit string computed in decimal, so we do this manually
788 // here.
789 Val = 0;
790 for (unsigned i = 0; i != ActualLength; ++i) {
791 if (!isdigit(DigitTokBegin[i])) {
792 PP.Diag(PP.AdvanceToTokenCharacter(DigitTok.getLocation(), i),
793 diag::err_pp_line_digit_sequence);
794 PP.DiscardUntilEndOfDirective();
795 return true;
796 }
797
798 unsigned NextVal = Val*10+(DigitTokBegin[i]-'0');
799 if (NextVal < Val) { // overflow.
800 PP.Diag(DigitTok, DiagID);
801 PP.DiscardUntilEndOfDirective();
802 return true;
803 }
804 Val = NextVal;
805 }
806
807 if (DigitTokBegin[0] == '0' && Val)
808 PP.Diag(DigitTok.getLocation(), diag::warn_pp_line_decimal);
809
810 return false;
811 }
812
813 /// \brief Handle a \#line directive: C99 6.10.4.
814 ///
815 /// The two acceptable forms are:
816 /// \verbatim
817 /// # line digit-sequence
818 /// # line digit-sequence "s-char-sequence"
819 /// \endverbatim
HandleLineDirective(Token & Tok)820 void Preprocessor::HandleLineDirective(Token &Tok) {
821 // Read the line # and string argument. Per C99 6.10.4p5, these tokens are
822 // expanded.
823 Token DigitTok;
824 Lex(DigitTok);
825
826 // Validate the number and convert it to an unsigned.
827 unsigned LineNo;
828 if (GetLineValue(DigitTok, LineNo, diag::err_pp_line_requires_integer,*this))
829 return;
830
831 if (LineNo == 0)
832 Diag(DigitTok, diag::ext_pp_line_zero);
833
834 // Enforce C99 6.10.4p3: "The digit sequence shall not specify ... a
835 // number greater than 2147483647". C90 requires that the line # be <= 32767.
836 unsigned LineLimit = 32768U;
837 if (LangOpts.C99 || LangOpts.CPlusPlus0x)
838 LineLimit = 2147483648U;
839 if (LineNo >= LineLimit)
840 Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit;
841 else if (LangOpts.CPlusPlus0x && LineNo >= 32768U)
842 Diag(DigitTok, diag::warn_cxx98_compat_pp_line_too_big);
843
844 int FilenameID = -1;
845 Token StrTok;
846 Lex(StrTok);
847
848 // If the StrTok is "eod", then it wasn't present. Otherwise, it must be a
849 // string followed by eod.
850 if (StrTok.is(tok::eod))
851 ; // ok
852 else if (StrTok.isNot(tok::string_literal)) {
853 Diag(StrTok, diag::err_pp_line_invalid_filename);
854 return DiscardUntilEndOfDirective();
855 } else if (StrTok.hasUDSuffix()) {
856 Diag(StrTok, diag::err_invalid_string_udl);
857 return DiscardUntilEndOfDirective();
858 } else {
859 // Parse and validate the string, converting it into a unique ID.
860 StringLiteralParser Literal(&StrTok, 1, *this);
861 assert(Literal.isAscii() && "Didn't allow wide strings in");
862 if (Literal.hadError)
863 return DiscardUntilEndOfDirective();
864 if (Literal.Pascal) {
865 Diag(StrTok, diag::err_pp_linemarker_invalid_filename);
866 return DiscardUntilEndOfDirective();
867 }
868 FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString());
869
870 // Verify that there is nothing after the string, other than EOD. Because
871 // of C99 6.10.4p5, macros that expand to empty tokens are ok.
872 CheckEndOfDirective("line", true);
873 }
874
875 SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID);
876
877 if (Callbacks)
878 Callbacks->FileChanged(CurPPLexer->getSourceLocation(),
879 PPCallbacks::RenameFile,
880 SrcMgr::C_User);
881 }
882
883 /// ReadLineMarkerFlags - Parse and validate any flags at the end of a GNU line
884 /// marker directive.
ReadLineMarkerFlags(bool & IsFileEntry,bool & IsFileExit,bool & IsSystemHeader,bool & IsExternCHeader,Preprocessor & PP)885 static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit,
886 bool &IsSystemHeader, bool &IsExternCHeader,
887 Preprocessor &PP) {
888 unsigned FlagVal;
889 Token FlagTok;
890 PP.Lex(FlagTok);
891 if (FlagTok.is(tok::eod)) return false;
892 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP))
893 return true;
894
895 if (FlagVal == 1) {
896 IsFileEntry = true;
897
898 PP.Lex(FlagTok);
899 if (FlagTok.is(tok::eod)) return false;
900 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP))
901 return true;
902 } else if (FlagVal == 2) {
903 IsFileExit = true;
904
905 SourceManager &SM = PP.getSourceManager();
906 // If we are leaving the current presumed file, check to make sure the
907 // presumed include stack isn't empty!
908 FileID CurFileID =
909 SM.getDecomposedExpansionLoc(FlagTok.getLocation()).first;
910 PresumedLoc PLoc = SM.getPresumedLoc(FlagTok.getLocation());
911 if (PLoc.isInvalid())
912 return true;
913
914 // If there is no include loc (main file) or if the include loc is in a
915 // different physical file, then we aren't in a "1" line marker flag region.
916 SourceLocation IncLoc = PLoc.getIncludeLoc();
917 if (IncLoc.isInvalid() ||
918 SM.getDecomposedExpansionLoc(IncLoc).first != CurFileID) {
919 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_pop);
920 PP.DiscardUntilEndOfDirective();
921 return true;
922 }
923
924 PP.Lex(FlagTok);
925 if (FlagTok.is(tok::eod)) return false;
926 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP))
927 return true;
928 }
929
930 // We must have 3 if there are still flags.
931 if (FlagVal != 3) {
932 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag);
933 PP.DiscardUntilEndOfDirective();
934 return true;
935 }
936
937 IsSystemHeader = true;
938
939 PP.Lex(FlagTok);
940 if (FlagTok.is(tok::eod)) return false;
941 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP))
942 return true;
943
944 // We must have 4 if there is yet another flag.
945 if (FlagVal != 4) {
946 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag);
947 PP.DiscardUntilEndOfDirective();
948 return true;
949 }
950
951 IsExternCHeader = true;
952
953 PP.Lex(FlagTok);
954 if (FlagTok.is(tok::eod)) return false;
955
956 // There are no more valid flags here.
957 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag);
958 PP.DiscardUntilEndOfDirective();
959 return true;
960 }
961
962 /// HandleDigitDirective - Handle a GNU line marker directive, whose syntax is
963 /// one of the following forms:
964 ///
965 /// # 42
966 /// # 42 "file" ('1' | '2')?
967 /// # 42 "file" ('1' | '2')? '3' '4'?
968 ///
HandleDigitDirective(Token & DigitTok)969 void Preprocessor::HandleDigitDirective(Token &DigitTok) {
970 // Validate the number and convert it to an unsigned. GNU does not have a
971 // line # limit other than it fit in 32-bits.
972 unsigned LineNo;
973 if (GetLineValue(DigitTok, LineNo, diag::err_pp_linemarker_requires_integer,
974 *this))
975 return;
976
977 Token StrTok;
978 Lex(StrTok);
979
980 bool IsFileEntry = false, IsFileExit = false;
981 bool IsSystemHeader = false, IsExternCHeader = false;
982 int FilenameID = -1;
983
984 // If the StrTok is "eod", then it wasn't present. Otherwise, it must be a
985 // string followed by eod.
986 if (StrTok.is(tok::eod))
987 ; // ok
988 else if (StrTok.isNot(tok::string_literal)) {
989 Diag(StrTok, diag::err_pp_linemarker_invalid_filename);
990 return DiscardUntilEndOfDirective();
991 } else if (StrTok.hasUDSuffix()) {
992 Diag(StrTok, diag::err_invalid_string_udl);
993 return DiscardUntilEndOfDirective();
994 } else {
995 // Parse and validate the string, converting it into a unique ID.
996 StringLiteralParser Literal(&StrTok, 1, *this);
997 assert(Literal.isAscii() && "Didn't allow wide strings in");
998 if (Literal.hadError)
999 return DiscardUntilEndOfDirective();
1000 if (Literal.Pascal) {
1001 Diag(StrTok, diag::err_pp_linemarker_invalid_filename);
1002 return DiscardUntilEndOfDirective();
1003 }
1004 FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString());
1005
1006 // If a filename was present, read any flags that are present.
1007 if (ReadLineMarkerFlags(IsFileEntry, IsFileExit,
1008 IsSystemHeader, IsExternCHeader, *this))
1009 return;
1010 }
1011
1012 // Create a line note with this information.
1013 SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID,
1014 IsFileEntry, IsFileExit,
1015 IsSystemHeader, IsExternCHeader);
1016
1017 // If the preprocessor has callbacks installed, notify them of the #line
1018 // change. This is used so that the line marker comes out in -E mode for
1019 // example.
1020 if (Callbacks) {
1021 PPCallbacks::FileChangeReason Reason = PPCallbacks::RenameFile;
1022 if (IsFileEntry)
1023 Reason = PPCallbacks::EnterFile;
1024 else if (IsFileExit)
1025 Reason = PPCallbacks::ExitFile;
1026 SrcMgr::CharacteristicKind FileKind = SrcMgr::C_User;
1027 if (IsExternCHeader)
1028 FileKind = SrcMgr::C_ExternCSystem;
1029 else if (IsSystemHeader)
1030 FileKind = SrcMgr::C_System;
1031
1032 Callbacks->FileChanged(CurPPLexer->getSourceLocation(), Reason, FileKind);
1033 }
1034 }
1035
1036
1037 /// HandleUserDiagnosticDirective - Handle a #warning or #error directive.
1038 ///
HandleUserDiagnosticDirective(Token & Tok,bool isWarning)1039 void Preprocessor::HandleUserDiagnosticDirective(Token &Tok,
1040 bool isWarning) {
1041 // PTH doesn't emit #warning or #error directives.
1042 if (CurPTHLexer)
1043 return CurPTHLexer->DiscardToEndOfLine();
1044
1045 // Read the rest of the line raw. We do this because we don't want macros
1046 // to be expanded and we don't require that the tokens be valid preprocessing
1047 // tokens. For example, this is allowed: "#warning ` 'foo". GCC does
1048 // collapse multiple consequtive white space between tokens, but this isn't
1049 // specified by the standard.
1050 SmallString<128> Message;
1051 CurLexer->ReadToEndOfLine(&Message);
1052
1053 // Find the first non-whitespace character, so that we can make the
1054 // diagnostic more succinct.
1055 StringRef Msg = Message.str().ltrim(" ");
1056
1057 if (isWarning)
1058 Diag(Tok, diag::pp_hash_warning) << Msg;
1059 else
1060 Diag(Tok, diag::err_pp_hash_error) << Msg;
1061 }
1062
1063 /// HandleIdentSCCSDirective - Handle a #ident/#sccs directive.
1064 ///
HandleIdentSCCSDirective(Token & Tok)1065 void Preprocessor::HandleIdentSCCSDirective(Token &Tok) {
1066 // Yes, this directive is an extension.
1067 Diag(Tok, diag::ext_pp_ident_directive);
1068
1069 // Read the string argument.
1070 Token StrTok;
1071 Lex(StrTok);
1072
1073 // If the token kind isn't a string, it's a malformed directive.
1074 if (StrTok.isNot(tok::string_literal) &&
1075 StrTok.isNot(tok::wide_string_literal)) {
1076 Diag(StrTok, diag::err_pp_malformed_ident);
1077 if (StrTok.isNot(tok::eod))
1078 DiscardUntilEndOfDirective();
1079 return;
1080 }
1081
1082 if (StrTok.hasUDSuffix()) {
1083 Diag(StrTok, diag::err_invalid_string_udl);
1084 return DiscardUntilEndOfDirective();
1085 }
1086
1087 // Verify that there is nothing after the string, other than EOD.
1088 CheckEndOfDirective("ident");
1089
1090 if (Callbacks) {
1091 bool Invalid = false;
1092 std::string Str = getSpelling(StrTok, &Invalid);
1093 if (!Invalid)
1094 Callbacks->Ident(Tok.getLocation(), Str);
1095 }
1096 }
1097
1098 /// \brief Handle a #public directive.
HandleMacroPublicDirective(Token & Tok)1099 void Preprocessor::HandleMacroPublicDirective(Token &Tok) {
1100 Token MacroNameTok;
1101 ReadMacroName(MacroNameTok, 2);
1102
1103 // Error reading macro name? If so, diagnostic already issued.
1104 if (MacroNameTok.is(tok::eod))
1105 return;
1106
1107 // Check to see if this is the last token on the #__public_macro line.
1108 CheckEndOfDirective("__public_macro");
1109
1110 // Okay, we finally have a valid identifier to undef.
1111 MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo());
1112
1113 // If the macro is not defined, this is an error.
1114 if (MI == 0) {
1115 Diag(MacroNameTok, diag::err_pp_visibility_non_macro)
1116 << MacroNameTok.getIdentifierInfo();
1117 return;
1118 }
1119
1120 // Note that this macro has now been exported.
1121 MI->setVisibility(/*IsPublic=*/true, MacroNameTok.getLocation());
1122
1123 // If this macro definition came from a PCH file, mark it
1124 // as having changed since serialization.
1125 if (MI->isFromAST())
1126 MI->setChangedAfterLoad();
1127 }
1128
1129 /// \brief Handle a #private directive.
HandleMacroPrivateDirective(Token & Tok)1130 void Preprocessor::HandleMacroPrivateDirective(Token &Tok) {
1131 Token MacroNameTok;
1132 ReadMacroName(MacroNameTok, 2);
1133
1134 // Error reading macro name? If so, diagnostic already issued.
1135 if (MacroNameTok.is(tok::eod))
1136 return;
1137
1138 // Check to see if this is the last token on the #__private_macro line.
1139 CheckEndOfDirective("__private_macro");
1140
1141 // Okay, we finally have a valid identifier to undef.
1142 MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo());
1143
1144 // If the macro is not defined, this is an error.
1145 if (MI == 0) {
1146 Diag(MacroNameTok, diag::err_pp_visibility_non_macro)
1147 << MacroNameTok.getIdentifierInfo();
1148 return;
1149 }
1150
1151 // Note that this macro has now been marked private.
1152 MI->setVisibility(/*IsPublic=*/false, MacroNameTok.getLocation());
1153
1154 // If this macro definition came from a PCH file, mark it
1155 // as having changed since serialization.
1156 if (MI->isFromAST())
1157 MI->setChangedAfterLoad();
1158 }
1159
1160 //===----------------------------------------------------------------------===//
1161 // Preprocessor Include Directive Handling.
1162 //===----------------------------------------------------------------------===//
1163
1164 /// GetIncludeFilenameSpelling - Turn the specified lexer token into a fully
1165 /// checked and spelled filename, e.g. as an operand of \#include. This returns
1166 /// true if the input filename was in <>'s or false if it were in ""'s. The
1167 /// caller is expected to provide a buffer that is large enough to hold the
1168 /// spelling of the filename, but is also expected to handle the case when
1169 /// this method decides to use a different buffer.
GetIncludeFilenameSpelling(SourceLocation Loc,StringRef & Buffer)1170 bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc,
1171 StringRef &Buffer) {
1172 // Get the text form of the filename.
1173 assert(!Buffer.empty() && "Can't have tokens with empty spellings!");
1174
1175 // Make sure the filename is <x> or "x".
1176 bool isAngled;
1177 if (Buffer[0] == '<') {
1178 if (Buffer.back() != '>') {
1179 Diag(Loc, diag::err_pp_expects_filename);
1180 Buffer = StringRef();
1181 return true;
1182 }
1183 isAngled = true;
1184 } else if (Buffer[0] == '"') {
1185 if (Buffer.back() != '"') {
1186 Diag(Loc, diag::err_pp_expects_filename);
1187 Buffer = StringRef();
1188 return true;
1189 }
1190 isAngled = false;
1191 } else {
1192 Diag(Loc, diag::err_pp_expects_filename);
1193 Buffer = StringRef();
1194 return true;
1195 }
1196
1197 // Diagnose #include "" as invalid.
1198 if (Buffer.size() <= 2) {
1199 Diag(Loc, diag::err_pp_empty_filename);
1200 Buffer = StringRef();
1201 return true;
1202 }
1203
1204 // Skip the brackets.
1205 Buffer = Buffer.substr(1, Buffer.size()-2);
1206 return isAngled;
1207 }
1208
1209 /// \brief Handle cases where the \#include name is expanded from a macro
1210 /// as multiple tokens, which need to be glued together.
1211 ///
1212 /// This occurs for code like:
1213 /// \code
1214 /// \#define FOO <a/b.h>
1215 /// \#include FOO
1216 /// \endcode
1217 /// because in this case, "<a/b.h>" is returned as 7 tokens, not one.
1218 ///
1219 /// This code concatenates and consumes tokens up to the '>' token. It returns
1220 /// false if the > was found, otherwise it returns true if it finds and consumes
1221 /// the EOD marker.
ConcatenateIncludeName(SmallString<128> & FilenameBuffer,SourceLocation & End)1222 bool Preprocessor::ConcatenateIncludeName(
1223 SmallString<128> &FilenameBuffer,
1224 SourceLocation &End) {
1225 Token CurTok;
1226
1227 Lex(CurTok);
1228 while (CurTok.isNot(tok::eod)) {
1229 End = CurTok.getLocation();
1230
1231 // FIXME: Provide code completion for #includes.
1232 if (CurTok.is(tok::code_completion)) {
1233 setCodeCompletionReached();
1234 Lex(CurTok);
1235 continue;
1236 }
1237
1238 // Append the spelling of this token to the buffer. If there was a space
1239 // before it, add it now.
1240 if (CurTok.hasLeadingSpace())
1241 FilenameBuffer.push_back(' ');
1242
1243 // Get the spelling of the token, directly into FilenameBuffer if possible.
1244 unsigned PreAppendSize = FilenameBuffer.size();
1245 FilenameBuffer.resize(PreAppendSize+CurTok.getLength());
1246
1247 const char *BufPtr = &FilenameBuffer[PreAppendSize];
1248 unsigned ActualLen = getSpelling(CurTok, BufPtr);
1249
1250 // If the token was spelled somewhere else, copy it into FilenameBuffer.
1251 if (BufPtr != &FilenameBuffer[PreAppendSize])
1252 memcpy(&FilenameBuffer[PreAppendSize], BufPtr, ActualLen);
1253
1254 // Resize FilenameBuffer to the correct size.
1255 if (CurTok.getLength() != ActualLen)
1256 FilenameBuffer.resize(PreAppendSize+ActualLen);
1257
1258 // If we found the '>' marker, return success.
1259 if (CurTok.is(tok::greater))
1260 return false;
1261
1262 Lex(CurTok);
1263 }
1264
1265 // If we hit the eod marker, emit an error and return true so that the caller
1266 // knows the EOD has been read.
1267 Diag(CurTok.getLocation(), diag::err_pp_expects_filename);
1268 return true;
1269 }
1270
1271 /// HandleIncludeDirective - The "\#include" tokens have just been read, read
1272 /// the file to be included from the lexer, then include it! This is a common
1273 /// routine with functionality shared between \#include, \#include_next and
1274 /// \#import. LookupFrom is set when this is a \#include_next directive, it
1275 /// specifies the file to start searching from.
HandleIncludeDirective(SourceLocation HashLoc,Token & IncludeTok,const DirectoryLookup * LookupFrom,bool isImport)1276 void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
1277 Token &IncludeTok,
1278 const DirectoryLookup *LookupFrom,
1279 bool isImport) {
1280
1281 Token FilenameTok;
1282 CurPPLexer->LexIncludeFilename(FilenameTok);
1283
1284 // Reserve a buffer to get the spelling.
1285 SmallString<128> FilenameBuffer;
1286 StringRef Filename;
1287 SourceLocation End;
1288 SourceLocation CharEnd; // the end of this directive, in characters
1289
1290 switch (FilenameTok.getKind()) {
1291 case tok::eod:
1292 // If the token kind is EOD, the error has already been diagnosed.
1293 return;
1294
1295 case tok::angle_string_literal:
1296 case tok::string_literal:
1297 Filename = getSpelling(FilenameTok, FilenameBuffer);
1298 End = FilenameTok.getLocation();
1299 CharEnd = End.getLocWithOffset(Filename.size());
1300 break;
1301
1302 case tok::less:
1303 // This could be a <foo/bar.h> file coming from a macro expansion. In this
1304 // case, glue the tokens together into FilenameBuffer and interpret those.
1305 FilenameBuffer.push_back('<');
1306 if (ConcatenateIncludeName(FilenameBuffer, End))
1307 return; // Found <eod> but no ">"? Diagnostic already emitted.
1308 Filename = FilenameBuffer.str();
1309 CharEnd = getLocForEndOfToken(End);
1310 break;
1311 default:
1312 Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename);
1313 DiscardUntilEndOfDirective();
1314 return;
1315 }
1316
1317 StringRef OriginalFilename = Filename;
1318 bool isAngled =
1319 GetIncludeFilenameSpelling(FilenameTok.getLocation(), Filename);
1320 // If GetIncludeFilenameSpelling set the start ptr to null, there was an
1321 // error.
1322 if (Filename.empty()) {
1323 DiscardUntilEndOfDirective();
1324 return;
1325 }
1326
1327 // Verify that there is nothing after the filename, other than EOD. Note that
1328 // we allow macros that expand to nothing after the filename, because this
1329 // falls into the category of "#include pp-tokens new-line" specified in
1330 // C99 6.10.2p4.
1331 CheckEndOfDirective(IncludeTok.getIdentifierInfo()->getNameStart(), true);
1332
1333 // Check that we don't have infinite #include recursion.
1334 if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1) {
1335 Diag(FilenameTok, diag::err_pp_include_too_deep);
1336 return;
1337 }
1338
1339 // Complain about attempts to #include files in an audit pragma.
1340 if (PragmaARCCFCodeAuditedLoc.isValid()) {
1341 Diag(HashLoc, diag::err_pp_include_in_arc_cf_code_audited);
1342 Diag(PragmaARCCFCodeAuditedLoc, diag::note_pragma_entered_here);
1343
1344 // Immediately leave the pragma.
1345 PragmaARCCFCodeAuditedLoc = SourceLocation();
1346 }
1347
1348 if (HeaderInfo.HasIncludeAliasMap()) {
1349 // Map the filename with the brackets still attached. If the name doesn't
1350 // map to anything, fall back on the filename we've already gotten the
1351 // spelling for.
1352 StringRef NewName = HeaderInfo.MapHeaderToIncludeAlias(OriginalFilename);
1353 if (!NewName.empty())
1354 Filename = NewName;
1355 }
1356
1357 // Search include directories.
1358 const DirectoryLookup *CurDir;
1359 SmallString<1024> SearchPath;
1360 SmallString<1024> RelativePath;
1361 // We get the raw path only if we have 'Callbacks' to which we later pass
1362 // the path.
1363 Module *SuggestedModule = 0;
1364 const FileEntry *File = LookupFile(
1365 Filename, isAngled, LookupFrom, CurDir,
1366 Callbacks ? &SearchPath : NULL, Callbacks ? &RelativePath : NULL,
1367 getLangOpts().Modules? &SuggestedModule : 0);
1368
1369 if (Callbacks) {
1370 if (!File) {
1371 // Give the clients a chance to recover.
1372 SmallString<128> RecoveryPath;
1373 if (Callbacks->FileNotFound(Filename, RecoveryPath)) {
1374 if (const DirectoryEntry *DE = FileMgr.getDirectory(RecoveryPath)) {
1375 // Add the recovery path to the list of search paths.
1376 DirectoryLookup DL(DE, SrcMgr::C_User, true, false);
1377 HeaderInfo.AddSearchPath(DL, isAngled);
1378
1379 // Try the lookup again, skipping the cache.
1380 File = LookupFile(Filename, isAngled, LookupFrom, CurDir, 0, 0,
1381 getLangOpts().Modules? &SuggestedModule : 0,
1382 /*SkipCache*/true);
1383 }
1384 }
1385 }
1386
1387 // Notify the callback object that we've seen an inclusion directive.
1388 Callbacks->InclusionDirective(HashLoc, IncludeTok, Filename, isAngled, File,
1389 End, SearchPath, RelativePath);
1390 }
1391
1392 if (File == 0) {
1393 if (!SuppressIncludeNotFoundError) {
1394 // If the file could not be located and it was included via angle
1395 // brackets, we can attempt a lookup as though it were a quoted path to
1396 // provide the user with a possible fixit.
1397 if (isAngled) {
1398 File = LookupFile(Filename, false, LookupFrom, CurDir,
1399 Callbacks ? &SearchPath : 0,
1400 Callbacks ? &RelativePath : 0,
1401 getLangOpts().Modules ? &SuggestedModule : 0);
1402 if (File) {
1403 SourceRange Range(FilenameTok.getLocation(), CharEnd);
1404 Diag(FilenameTok, diag::err_pp_file_not_found_not_fatal) <<
1405 Filename <<
1406 FixItHint::CreateReplacement(Range, "\"" + Filename.str() + "\"");
1407 }
1408 }
1409 // If the file is still not found, just go with the vanilla diagnostic
1410 if (!File)
1411 Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
1412 }
1413 if (!File)
1414 return;
1415 }
1416
1417 // If we are supposed to import a module rather than including the header,
1418 // do so now.
1419 if (SuggestedModule) {
1420 // Compute the module access path corresponding to this module.
1421 // FIXME: Should we have a second loadModule() overload to avoid this
1422 // extra lookup step?
1423 llvm::SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1424 for (Module *Mod = SuggestedModule; Mod; Mod = Mod->Parent)
1425 Path.push_back(std::make_pair(getIdentifierInfo(Mod->Name),
1426 FilenameTok.getLocation()));
1427 std::reverse(Path.begin(), Path.end());
1428
1429 // Warn that we're replacing the include/import with a module import.
1430 SmallString<128> PathString;
1431 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
1432 if (I)
1433 PathString += '.';
1434 PathString += Path[I].first->getName();
1435 }
1436 int IncludeKind = 0;
1437
1438 switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
1439 case tok::pp_include:
1440 IncludeKind = 0;
1441 break;
1442
1443 case tok::pp_import:
1444 IncludeKind = 1;
1445 break;
1446
1447 case tok::pp_include_next:
1448 IncludeKind = 2;
1449 break;
1450
1451 case tok::pp___include_macros:
1452 IncludeKind = 3;
1453 break;
1454
1455 default:
1456 llvm_unreachable("unknown include directive kind");
1457 }
1458
1459 // Determine whether we are actually building the module that this
1460 // include directive maps to.
1461 bool BuildingImportedModule
1462 = Path[0].first->getName() == getLangOpts().CurrentModule;
1463
1464 if (!BuildingImportedModule && getLangOpts().ObjC2) {
1465 // If we're not building the imported module, warn that we're going
1466 // to automatically turn this inclusion directive into a module import.
1467 // We only do this in Objective-C, where we have a module-import syntax.
1468 CharSourceRange ReplaceRange(SourceRange(HashLoc, CharEnd),
1469 /*IsTokenRange=*/false);
1470 Diag(HashLoc, diag::warn_auto_module_import)
1471 << IncludeKind << PathString
1472 << FixItHint::CreateReplacement(ReplaceRange,
1473 "@__experimental_modules_import " + PathString.str().str() + ";");
1474 }
1475
1476 // Load the module.
1477 // If this was an #__include_macros directive, only make macros visible.
1478 Module::NameVisibilityKind Visibility
1479 = (IncludeKind == 3)? Module::MacrosVisible : Module::AllVisible;
1480 Module *Imported
1481 = TheModuleLoader.loadModule(IncludeTok.getLocation(), Path, Visibility,
1482 /*IsIncludeDirective=*/true);
1483
1484 // If this header isn't part of the module we're building, we're done.
1485 if (!BuildingImportedModule && Imported)
1486 return;
1487 }
1488
1489 // The #included file will be considered to be a system header if either it is
1490 // in a system include directory, or if the #includer is a system include
1491 // header.
1492 SrcMgr::CharacteristicKind FileCharacter =
1493 std::max(HeaderInfo.getFileDirFlavor(File),
1494 SourceMgr.getFileCharacteristic(FilenameTok.getLocation()));
1495
1496 // Ask HeaderInfo if we should enter this #include file. If not, #including
1497 // this file will have no effect.
1498 if (!HeaderInfo.ShouldEnterIncludeFile(File, isImport)) {
1499 if (Callbacks)
1500 Callbacks->FileSkipped(*File, FilenameTok, FileCharacter);
1501 return;
1502 }
1503
1504 // Look up the file, create a File ID for it.
1505 SourceLocation IncludePos = End;
1506 // If the filename string was the result of macro expansions, set the include
1507 // position on the file where it will be included and after the expansions.
1508 if (IncludePos.isMacroID())
1509 IncludePos = SourceMgr.getExpansionRange(IncludePos).second;
1510 FileID FID = SourceMgr.createFileID(File, IncludePos, FileCharacter);
1511 assert(!FID.isInvalid() && "Expected valid file ID");
1512
1513 // Finally, if all is good, enter the new file!
1514 EnterSourceFile(FID, CurDir, FilenameTok.getLocation());
1515 }
1516
1517 /// HandleIncludeNextDirective - Implements \#include_next.
1518 ///
HandleIncludeNextDirective(SourceLocation HashLoc,Token & IncludeNextTok)1519 void Preprocessor::HandleIncludeNextDirective(SourceLocation HashLoc,
1520 Token &IncludeNextTok) {
1521 Diag(IncludeNextTok, diag::ext_pp_include_next_directive);
1522
1523 // #include_next is like #include, except that we start searching after
1524 // the current found directory. If we can't do this, issue a
1525 // diagnostic.
1526 const DirectoryLookup *Lookup = CurDirLookup;
1527 if (isInPrimaryFile()) {
1528 Lookup = 0;
1529 Diag(IncludeNextTok, diag::pp_include_next_in_primary);
1530 } else if (Lookup == 0) {
1531 Diag(IncludeNextTok, diag::pp_include_next_absolute_path);
1532 } else {
1533 // Start looking up in the next directory.
1534 ++Lookup;
1535 }
1536
1537 return HandleIncludeDirective(HashLoc, IncludeNextTok, Lookup);
1538 }
1539
1540 /// HandleMicrosoftImportDirective - Implements \#import for Microsoft Mode
HandleMicrosoftImportDirective(Token & Tok)1541 void Preprocessor::HandleMicrosoftImportDirective(Token &Tok) {
1542 // The Microsoft #import directive takes a type library and generates header
1543 // files from it, and includes those. This is beyond the scope of what clang
1544 // does, so we ignore it and error out. However, #import can optionally have
1545 // trailing attributes that span multiple lines. We're going to eat those
1546 // so we can continue processing from there.
1547 Diag(Tok, diag::err_pp_import_directive_ms );
1548
1549 // Read tokens until we get to the end of the directive. Note that the
1550 // directive can be split over multiple lines using the backslash character.
1551 DiscardUntilEndOfDirective();
1552 }
1553
1554 /// HandleImportDirective - Implements \#import.
1555 ///
HandleImportDirective(SourceLocation HashLoc,Token & ImportTok)1556 void Preprocessor::HandleImportDirective(SourceLocation HashLoc,
1557 Token &ImportTok) {
1558 if (!LangOpts.ObjC1) { // #import is standard for ObjC.
1559 if (LangOpts.MicrosoftMode)
1560 return HandleMicrosoftImportDirective(ImportTok);
1561 Diag(ImportTok, diag::ext_pp_import_directive);
1562 }
1563 return HandleIncludeDirective(HashLoc, ImportTok, 0, true);
1564 }
1565
1566 /// HandleIncludeMacrosDirective - The -imacros command line option turns into a
1567 /// pseudo directive in the predefines buffer. This handles it by sucking all
1568 /// tokens through the preprocessor and discarding them (only keeping the side
1569 /// effects on the preprocessor).
HandleIncludeMacrosDirective(SourceLocation HashLoc,Token & IncludeMacrosTok)1570 void Preprocessor::HandleIncludeMacrosDirective(SourceLocation HashLoc,
1571 Token &IncludeMacrosTok) {
1572 // This directive should only occur in the predefines buffer. If not, emit an
1573 // error and reject it.
1574 SourceLocation Loc = IncludeMacrosTok.getLocation();
1575 if (strcmp(SourceMgr.getBufferName(Loc), "<built-in>") != 0) {
1576 Diag(IncludeMacrosTok.getLocation(),
1577 diag::pp_include_macros_out_of_predefines);
1578 DiscardUntilEndOfDirective();
1579 return;
1580 }
1581
1582 // Treat this as a normal #include for checking purposes. If this is
1583 // successful, it will push a new lexer onto the include stack.
1584 HandleIncludeDirective(HashLoc, IncludeMacrosTok, 0, false);
1585
1586 Token TmpTok;
1587 do {
1588 Lex(TmpTok);
1589 assert(TmpTok.isNot(tok::eof) && "Didn't find end of -imacros!");
1590 } while (TmpTok.isNot(tok::hashhash));
1591 }
1592
1593 //===----------------------------------------------------------------------===//
1594 // Preprocessor Macro Directive Handling.
1595 //===----------------------------------------------------------------------===//
1596
1597 /// ReadMacroDefinitionArgList - The ( starting an argument list of a macro
1598 /// definition has just been read. Lex the rest of the arguments and the
1599 /// closing ), updating MI with what we learn. Return true if an error occurs
1600 /// parsing the arg list.
ReadMacroDefinitionArgList(MacroInfo * MI,Token & Tok)1601 bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI, Token &Tok) {
1602 SmallVector<IdentifierInfo*, 32> Arguments;
1603
1604 while (1) {
1605 LexUnexpandedToken(Tok);
1606 switch (Tok.getKind()) {
1607 case tok::r_paren:
1608 // Found the end of the argument list.
1609 if (Arguments.empty()) // #define FOO()
1610 return false;
1611 // Otherwise we have #define FOO(A,)
1612 Diag(Tok, diag::err_pp_expected_ident_in_arg_list);
1613 return true;
1614 case tok::ellipsis: // #define X(... -> C99 varargs
1615 if (!LangOpts.C99)
1616 Diag(Tok, LangOpts.CPlusPlus0x ?
1617 diag::warn_cxx98_compat_variadic_macro :
1618 diag::ext_variadic_macro);
1619
1620 // Lex the token after the identifier.
1621 LexUnexpandedToken(Tok);
1622 if (Tok.isNot(tok::r_paren)) {
1623 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
1624 return true;
1625 }
1626 // Add the __VA_ARGS__ identifier as an argument.
1627 Arguments.push_back(Ident__VA_ARGS__);
1628 MI->setIsC99Varargs();
1629 MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
1630 return false;
1631 case tok::eod: // #define X(
1632 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
1633 return true;
1634 default:
1635 // Handle keywords and identifiers here to accept things like
1636 // #define Foo(for) for.
1637 IdentifierInfo *II = Tok.getIdentifierInfo();
1638 if (II == 0) {
1639 // #define X(1
1640 Diag(Tok, diag::err_pp_invalid_tok_in_arg_list);
1641 return true;
1642 }
1643
1644 // If this is already used as an argument, it is used multiple times (e.g.
1645 // #define X(A,A.
1646 if (std::find(Arguments.begin(), Arguments.end(), II) !=
1647 Arguments.end()) { // C99 6.10.3p6
1648 Diag(Tok, diag::err_pp_duplicate_name_in_arg_list) << II;
1649 return true;
1650 }
1651
1652 // Add the argument to the macro info.
1653 Arguments.push_back(II);
1654
1655 // Lex the token after the identifier.
1656 LexUnexpandedToken(Tok);
1657
1658 switch (Tok.getKind()) {
1659 default: // #define X(A B
1660 Diag(Tok, diag::err_pp_expected_comma_in_arg_list);
1661 return true;
1662 case tok::r_paren: // #define X(A)
1663 MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
1664 return false;
1665 case tok::comma: // #define X(A,
1666 break;
1667 case tok::ellipsis: // #define X(A... -> GCC extension
1668 // Diagnose extension.
1669 Diag(Tok, diag::ext_named_variadic_macro);
1670
1671 // Lex the token after the identifier.
1672 LexUnexpandedToken(Tok);
1673 if (Tok.isNot(tok::r_paren)) {
1674 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
1675 return true;
1676 }
1677
1678 MI->setIsGNUVarargs();
1679 MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
1680 return false;
1681 }
1682 }
1683 }
1684 }
1685
1686 /// HandleDefineDirective - Implements \#define. This consumes the entire macro
1687 /// line then lets the caller lex the next real token.
HandleDefineDirective(Token & DefineTok)1688 void Preprocessor::HandleDefineDirective(Token &DefineTok) {
1689 ++NumDefined;
1690
1691 Token MacroNameTok;
1692 ReadMacroName(MacroNameTok, 1);
1693
1694 // Error reading macro name? If so, diagnostic already issued.
1695 if (MacroNameTok.is(tok::eod))
1696 return;
1697
1698 Token LastTok = MacroNameTok;
1699
1700 // If we are supposed to keep comments in #defines, reenable comment saving
1701 // mode.
1702 if (CurLexer) CurLexer->SetCommentRetentionState(KeepMacroComments);
1703
1704 // Create the new macro.
1705 MacroInfo *MI = AllocateMacroInfo(MacroNameTok.getLocation());
1706
1707 Token Tok;
1708 LexUnexpandedToken(Tok);
1709
1710 // If this is a function-like macro definition, parse the argument list,
1711 // marking each of the identifiers as being used as macro arguments. Also,
1712 // check other constraints on the first token of the macro body.
1713 if (Tok.is(tok::eod)) {
1714 // If there is no body to this macro, we have no special handling here.
1715 } else if (Tok.hasLeadingSpace()) {
1716 // This is a normal token with leading space. Clear the leading space
1717 // marker on the first token to get proper expansion.
1718 Tok.clearFlag(Token::LeadingSpace);
1719 } else if (Tok.is(tok::l_paren)) {
1720 // This is a function-like macro definition. Read the argument list.
1721 MI->setIsFunctionLike();
1722 if (ReadMacroDefinitionArgList(MI, LastTok)) {
1723 // Forget about MI.
1724 ReleaseMacroInfo(MI);
1725 // Throw away the rest of the line.
1726 if (CurPPLexer->ParsingPreprocessorDirective)
1727 DiscardUntilEndOfDirective();
1728 return;
1729 }
1730
1731 // If this is a definition of a variadic C99 function-like macro, not using
1732 // the GNU named varargs extension, enabled __VA_ARGS__.
1733
1734 // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
1735 // This gets unpoisoned where it is allowed.
1736 assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned!");
1737 if (MI->isC99Varargs())
1738 Ident__VA_ARGS__->setIsPoisoned(false);
1739
1740 // Read the first token after the arg list for down below.
1741 LexUnexpandedToken(Tok);
1742 } else if (LangOpts.C99 || LangOpts.CPlusPlus0x) {
1743 // C99 requires whitespace between the macro definition and the body. Emit
1744 // a diagnostic for something like "#define X+".
1745 Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name);
1746 } else {
1747 // C90 6.8 TC1 says: "In the definition of an object-like macro, if the
1748 // first character of a replacement list is not a character required by
1749 // subclause 5.2.1, then there shall be white-space separation between the
1750 // identifier and the replacement list.". 5.2.1 lists this set:
1751 // "A-Za-z0-9!"#%&'()*+,_./:;<=>?[\]^_{|}~" as well as whitespace, which
1752 // is irrelevant here.
1753 bool isInvalid = false;
1754 if (Tok.is(tok::at)) // @ is not in the list above.
1755 isInvalid = true;
1756 else if (Tok.is(tok::unknown)) {
1757 // If we have an unknown token, it is something strange like "`". Since
1758 // all of valid characters would have lexed into a single character
1759 // token of some sort, we know this is not a valid case.
1760 isInvalid = true;
1761 }
1762 if (isInvalid)
1763 Diag(Tok, diag::ext_missing_whitespace_after_macro_name);
1764 else
1765 Diag(Tok, diag::warn_missing_whitespace_after_macro_name);
1766 }
1767
1768 if (!Tok.is(tok::eod))
1769 LastTok = Tok;
1770
1771 // Read the rest of the macro body.
1772 if (MI->isObjectLike()) {
1773 // Object-like macros are very simple, just read their body.
1774 while (Tok.isNot(tok::eod)) {
1775 LastTok = Tok;
1776 MI->AddTokenToBody(Tok);
1777 // Get the next token of the macro.
1778 LexUnexpandedToken(Tok);
1779 }
1780
1781 } else {
1782 // Otherwise, read the body of a function-like macro. While we are at it,
1783 // check C99 6.10.3.2p1: ensure that # operators are followed by macro
1784 // parameters in function-like macro expansions.
1785 while (Tok.isNot(tok::eod)) {
1786 LastTok = Tok;
1787
1788 if (Tok.isNot(tok::hash)) {
1789 MI->AddTokenToBody(Tok);
1790
1791 // Get the next token of the macro.
1792 LexUnexpandedToken(Tok);
1793 continue;
1794 }
1795
1796 // Get the next token of the macro.
1797 LexUnexpandedToken(Tok);
1798
1799 // Check for a valid macro arg identifier.
1800 if (Tok.getIdentifierInfo() == 0 ||
1801 MI->getArgumentNum(Tok.getIdentifierInfo()) == -1) {
1802
1803 // If this is assembler-with-cpp mode, we accept random gibberish after
1804 // the '#' because '#' is often a comment character. However, change
1805 // the kind of the token to tok::unknown so that the preprocessor isn't
1806 // confused.
1807 if (getLangOpts().AsmPreprocessor && Tok.isNot(tok::eod)) {
1808 LastTok.setKind(tok::unknown);
1809 } else {
1810 Diag(Tok, diag::err_pp_stringize_not_parameter);
1811 ReleaseMacroInfo(MI);
1812
1813 // Disable __VA_ARGS__ again.
1814 Ident__VA_ARGS__->setIsPoisoned(true);
1815 return;
1816 }
1817 }
1818
1819 // Things look ok, add the '#' and param name tokens to the macro.
1820 MI->AddTokenToBody(LastTok);
1821 MI->AddTokenToBody(Tok);
1822 LastTok = Tok;
1823
1824 // Get the next token of the macro.
1825 LexUnexpandedToken(Tok);
1826 }
1827 }
1828
1829
1830 // Disable __VA_ARGS__ again.
1831 Ident__VA_ARGS__->setIsPoisoned(true);
1832
1833 // Check that there is no paste (##) operator at the beginning or end of the
1834 // replacement list.
1835 unsigned NumTokens = MI->getNumTokens();
1836 if (NumTokens != 0) {
1837 if (MI->getReplacementToken(0).is(tok::hashhash)) {
1838 Diag(MI->getReplacementToken(0), diag::err_paste_at_start);
1839 ReleaseMacroInfo(MI);
1840 return;
1841 }
1842 if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) {
1843 Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end);
1844 ReleaseMacroInfo(MI);
1845 return;
1846 }
1847 }
1848
1849 MI->setDefinitionEndLoc(LastTok.getLocation());
1850
1851 // Finally, if this identifier already had a macro defined for it, verify that
1852 // the macro bodies are identical, and issue diagnostics if they are not.
1853 if (MacroInfo *OtherMI = getMacroInfo(MacroNameTok.getIdentifierInfo())) {
1854 // It is very common for system headers to have tons of macro redefinitions
1855 // and for warnings to be disabled in system headers. If this is the case,
1856 // then don't bother calling MacroInfo::isIdenticalTo.
1857 if (!getDiagnostics().getSuppressSystemWarnings() ||
1858 !SourceMgr.isInSystemHeader(DefineTok.getLocation())) {
1859 if (!OtherMI->isUsed() && OtherMI->isWarnIfUnused())
1860 Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used);
1861
1862 // Macros must be identical. This means all tokens and whitespace
1863 // separation must be the same. C99 6.10.3.2.
1864 if (!OtherMI->isAllowRedefinitionsWithoutWarning() &&
1865 !MI->isIdenticalTo(*OtherMI, *this)) {
1866 Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef)
1867 << MacroNameTok.getIdentifierInfo();
1868 Diag(OtherMI->getDefinitionLoc(), diag::note_previous_definition);
1869 }
1870 }
1871 if (OtherMI->isWarnIfUnused())
1872 WarnUnusedMacroLocs.erase(OtherMI->getDefinitionLoc());
1873 }
1874
1875 setMacroInfo(MacroNameTok.getIdentifierInfo(), MI);
1876
1877 assert(!MI->isUsed());
1878 // If we need warning for not using the macro, add its location in the
1879 // warn-because-unused-macro set. If it gets used it will be removed from set.
1880 if (isInPrimaryFile() && // don't warn for include'd macros.
1881 Diags->getDiagnosticLevel(diag::pp_macro_not_used,
1882 MI->getDefinitionLoc()) != DiagnosticsEngine::Ignored) {
1883 MI->setIsWarnIfUnused(true);
1884 WarnUnusedMacroLocs.insert(MI->getDefinitionLoc());
1885 }
1886
1887 // If the callbacks want to know, tell them about the macro definition.
1888 if (Callbacks)
1889 Callbacks->MacroDefined(MacroNameTok, MI);
1890 }
1891
1892 /// HandleUndefDirective - Implements \#undef.
1893 ///
HandleUndefDirective(Token & UndefTok)1894 void Preprocessor::HandleUndefDirective(Token &UndefTok) {
1895 ++NumUndefined;
1896
1897 Token MacroNameTok;
1898 ReadMacroName(MacroNameTok, 2);
1899
1900 // Error reading macro name? If so, diagnostic already issued.
1901 if (MacroNameTok.is(tok::eod))
1902 return;
1903
1904 // Check to see if this is the last token on the #undef line.
1905 CheckEndOfDirective("undef");
1906
1907 // Okay, we finally have a valid identifier to undef.
1908 MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo());
1909
1910 // If the macro is not defined, this is a noop undef, just return.
1911 if (MI == 0) return;
1912
1913 if (!MI->isUsed() && MI->isWarnIfUnused())
1914 Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used);
1915
1916 // If the callbacks want to know, tell them about the macro #undef.
1917 if (Callbacks)
1918 Callbacks->MacroUndefined(MacroNameTok, MI);
1919
1920 if (MI->isWarnIfUnused())
1921 WarnUnusedMacroLocs.erase(MI->getDefinitionLoc());
1922
1923 MI->setUndefLoc(MacroNameTok.getLocation());
1924 clearMacroInfo(MacroNameTok.getIdentifierInfo());
1925 }
1926
1927
1928 //===----------------------------------------------------------------------===//
1929 // Preprocessor Conditional Directive Handling.
1930 //===----------------------------------------------------------------------===//
1931
1932 /// HandleIfdefDirective - Implements the \#ifdef/\#ifndef directive. isIfndef
1933 /// is true when this is a \#ifndef directive. ReadAnyTokensBeforeDirective is
1934 /// true if any tokens have been returned or pp-directives activated before this
1935 /// \#ifndef has been lexed.
1936 ///
HandleIfdefDirective(Token & Result,bool isIfndef,bool ReadAnyTokensBeforeDirective)1937 void Preprocessor::HandleIfdefDirective(Token &Result, bool isIfndef,
1938 bool ReadAnyTokensBeforeDirective) {
1939 ++NumIf;
1940 Token DirectiveTok = Result;
1941
1942 Token MacroNameTok;
1943 ReadMacroName(MacroNameTok);
1944
1945 // Error reading macro name? If so, diagnostic already issued.
1946 if (MacroNameTok.is(tok::eod)) {
1947 // Skip code until we get to #endif. This helps with recovery by not
1948 // emitting an error when the #endif is reached.
1949 SkipExcludedConditionalBlock(DirectiveTok.getLocation(),
1950 /*Foundnonskip*/false, /*FoundElse*/false);
1951 return;
1952 }
1953
1954 // Check to see if this is the last token on the #if[n]def line.
1955 CheckEndOfDirective(isIfndef ? "ifndef" : "ifdef");
1956
1957 IdentifierInfo *MII = MacroNameTok.getIdentifierInfo();
1958 MacroInfo *MI = getMacroInfo(MII);
1959
1960 if (CurPPLexer->getConditionalStackDepth() == 0) {
1961 // If the start of a top-level #ifdef and if the macro is not defined,
1962 // inform MIOpt that this might be the start of a proper include guard.
1963 // Otherwise it is some other form of unknown conditional which we can't
1964 // handle.
1965 if (!ReadAnyTokensBeforeDirective && MI == 0) {
1966 assert(isIfndef && "#ifdef shouldn't reach here");
1967 CurPPLexer->MIOpt.EnterTopLevelIFNDEF(MII);
1968 } else
1969 CurPPLexer->MIOpt.EnterTopLevelConditional();
1970 }
1971
1972 // If there is a macro, process it.
1973 if (MI) // Mark it used.
1974 markMacroAsUsed(MI);
1975
1976 if (Callbacks) {
1977 if (isIfndef)
1978 Callbacks->Ifndef(DirectiveTok.getLocation(), MacroNameTok);
1979 else
1980 Callbacks->Ifdef(DirectiveTok.getLocation(), MacroNameTok);
1981 }
1982
1983 // Should we include the stuff contained by this directive?
1984 if (!MI == isIfndef) {
1985 // Yes, remember that we are inside a conditional, then lex the next token.
1986 CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(),
1987 /*wasskip*/false, /*foundnonskip*/true,
1988 /*foundelse*/false);
1989 } else {
1990 // No, skip the contents of this block.
1991 SkipExcludedConditionalBlock(DirectiveTok.getLocation(),
1992 /*Foundnonskip*/false,
1993 /*FoundElse*/false);
1994 }
1995 }
1996
1997 /// HandleIfDirective - Implements the \#if directive.
1998 ///
HandleIfDirective(Token & IfToken,bool ReadAnyTokensBeforeDirective)1999 void Preprocessor::HandleIfDirective(Token &IfToken,
2000 bool ReadAnyTokensBeforeDirective) {
2001 ++NumIf;
2002
2003 // Parse and evaluate the conditional expression.
2004 IdentifierInfo *IfNDefMacro = 0;
2005 const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation();
2006 const bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro);
2007 const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation();
2008
2009 // If this condition is equivalent to #ifndef X, and if this is the first
2010 // directive seen, handle it for the multiple-include optimization.
2011 if (CurPPLexer->getConditionalStackDepth() == 0) {
2012 if (!ReadAnyTokensBeforeDirective && IfNDefMacro && ConditionalTrue)
2013 CurPPLexer->MIOpt.EnterTopLevelIFNDEF(IfNDefMacro);
2014 else
2015 CurPPLexer->MIOpt.EnterTopLevelConditional();
2016 }
2017
2018 if (Callbacks)
2019 Callbacks->If(IfToken.getLocation(),
2020 SourceRange(ConditionalBegin, ConditionalEnd));
2021
2022 // Should we include the stuff contained by this directive?
2023 if (ConditionalTrue) {
2024 // Yes, remember that we are inside a conditional, then lex the next token.
2025 CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false,
2026 /*foundnonskip*/true, /*foundelse*/false);
2027 } else {
2028 // No, skip the contents of this block.
2029 SkipExcludedConditionalBlock(IfToken.getLocation(), /*Foundnonskip*/false,
2030 /*FoundElse*/false);
2031 }
2032 }
2033
2034 /// HandleEndifDirective - Implements the \#endif directive.
2035 ///
HandleEndifDirective(Token & EndifToken)2036 void Preprocessor::HandleEndifDirective(Token &EndifToken) {
2037 ++NumEndif;
2038
2039 // Check that this is the whole directive.
2040 CheckEndOfDirective("endif");
2041
2042 PPConditionalInfo CondInfo;
2043 if (CurPPLexer->popConditionalLevel(CondInfo)) {
2044 // No conditionals on the stack: this is an #endif without an #if.
2045 Diag(EndifToken, diag::err_pp_endif_without_if);
2046 return;
2047 }
2048
2049 // If this the end of a top-level #endif, inform MIOpt.
2050 if (CurPPLexer->getConditionalStackDepth() == 0)
2051 CurPPLexer->MIOpt.ExitTopLevelConditional();
2052
2053 assert(!CondInfo.WasSkipping && !CurPPLexer->LexingRawMode &&
2054 "This code should only be reachable in the non-skipping case!");
2055
2056 if (Callbacks)
2057 Callbacks->Endif(EndifToken.getLocation(), CondInfo.IfLoc);
2058 }
2059
2060 /// HandleElseDirective - Implements the \#else directive.
2061 ///
HandleElseDirective(Token & Result)2062 void Preprocessor::HandleElseDirective(Token &Result) {
2063 ++NumElse;
2064
2065 // #else directive in a non-skipping conditional... start skipping.
2066 CheckEndOfDirective("else");
2067
2068 PPConditionalInfo CI;
2069 if (CurPPLexer->popConditionalLevel(CI)) {
2070 Diag(Result, diag::pp_err_else_without_if);
2071 return;
2072 }
2073
2074 // If this is a top-level #else, inform the MIOpt.
2075 if (CurPPLexer->getConditionalStackDepth() == 0)
2076 CurPPLexer->MIOpt.EnterTopLevelConditional();
2077
2078 // If this is a #else with a #else before it, report the error.
2079 if (CI.FoundElse) Diag(Result, diag::pp_err_else_after_else);
2080
2081 if (Callbacks)
2082 Callbacks->Else(Result.getLocation(), CI.IfLoc);
2083
2084 // Finally, skip the rest of the contents of this block.
2085 SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
2086 /*FoundElse*/true, Result.getLocation());
2087 }
2088
2089 /// HandleElifDirective - Implements the \#elif directive.
2090 ///
HandleElifDirective(Token & ElifToken)2091 void Preprocessor::HandleElifDirective(Token &ElifToken) {
2092 ++NumElse;
2093
2094 // #elif directive in a non-skipping conditional... start skipping.
2095 // We don't care what the condition is, because we will always skip it (since
2096 // the block immediately before it was included).
2097 const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation();
2098 DiscardUntilEndOfDirective();
2099 const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation();
2100
2101 PPConditionalInfo CI;
2102 if (CurPPLexer->popConditionalLevel(CI)) {
2103 Diag(ElifToken, diag::pp_err_elif_without_if);
2104 return;
2105 }
2106
2107 // If this is a top-level #elif, inform the MIOpt.
2108 if (CurPPLexer->getConditionalStackDepth() == 0)
2109 CurPPLexer->MIOpt.EnterTopLevelConditional();
2110
2111 // If this is a #elif with a #else before it, report the error.
2112 if (CI.FoundElse) Diag(ElifToken, diag::pp_err_elif_after_else);
2113
2114 if (Callbacks)
2115 Callbacks->Elif(ElifToken.getLocation(),
2116 SourceRange(ConditionalBegin, ConditionalEnd), CI.IfLoc);
2117
2118 // Finally, skip the rest of the contents of this block.
2119 SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
2120 /*FoundElse*/CI.FoundElse,
2121 ElifToken.getLocation());
2122 }
2123