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