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 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 50 MacroInfo *Preprocessor::AllocateMacroInfo(SourceLocation L) { 51 MacroInfo *MI = AllocateMacroInfo(); 52 new (MI) MacroInfo(L); 53 return MI; 54 } 55 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. 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. 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). 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. 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. 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 } 391 392 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 ""). 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. 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. 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" 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. 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 /// 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 /// 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 /// 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. 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. 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. 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 /// 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 /// 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). 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. 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. 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 /// 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 /// 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 /// 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 /// 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 /// 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 /// 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