PPDirectives.cpp revision be5c64d7a765acaf9454e7a511233771472bf811
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/Basic/SourceManager.h" 20#include "llvm/ADT/APInt.h" 21using namespace clang; 22 23//===----------------------------------------------------------------------===// 24// Utility Methods for Preprocessor Directive Handling. 25//===----------------------------------------------------------------------===// 26 27MacroInfo* Preprocessor::AllocateMacroInfo(SourceLocation L) { 28 MacroInfo *MI; 29 30 if (!MICache.empty()) { 31 MI = MICache.back(); 32 MICache.pop_back(); 33 } 34 else MI = (MacroInfo*) BP.Allocate<MacroInfo>(); 35 new (MI) MacroInfo(L); 36 return MI; 37} 38 39/// DiscardUntilEndOfDirective - Read and discard all tokens remaining on the 40/// current line until the tok::eom token is found. 41void Preprocessor::DiscardUntilEndOfDirective() { 42 Token Tmp; 43 do { 44 LexUnexpandedToken(Tmp); 45 } while (Tmp.isNot(tok::eom)); 46} 47 48/// ReadMacroName - Lex and validate a macro name, which occurs after a 49/// #define or #undef. This sets the token kind to eom and discards the rest 50/// of the macro line if the macro name is invalid. isDefineUndef is 1 if 51/// this is due to a a #define, 2 if #undef directive, 0 if it is something 52/// else (e.g. #ifdef). 53void Preprocessor::ReadMacroName(Token &MacroNameTok, char isDefineUndef) { 54 // Read the token, don't allow macro expansion on it. 55 LexUnexpandedToken(MacroNameTok); 56 57 // Missing macro name? 58 if (MacroNameTok.is(tok::eom)) { 59 Diag(MacroNameTok, diag::err_pp_missing_macro_name); 60 return; 61 } 62 63 IdentifierInfo *II = MacroNameTok.getIdentifierInfo(); 64 if (II == 0) { 65 std::string Spelling = getSpelling(MacroNameTok); 66 const IdentifierInfo &Info = Identifiers.get(Spelling); 67 if (Info.isCPlusPlusOperatorKeyword()) 68 // C++ 2.5p2: Alternative tokens behave the same as its primary token 69 // except for their spellings. 70 Diag(MacroNameTok, diag::err_pp_operator_used_as_macro_name) << Spelling; 71 else 72 Diag(MacroNameTok, diag::err_pp_macro_not_identifier); 73 // Fall through on error. 74 } else if (isDefineUndef && II->getPPKeywordID() == tok::pp_defined) { 75 // Error if defining "defined": C99 6.10.8.4. 76 Diag(MacroNameTok, diag::err_defined_macro_name); 77 } else if (isDefineUndef && II->hasMacroDefinition() && 78 getMacroInfo(II)->isBuiltinMacro()) { 79 // Error if defining "__LINE__" and other builtins: C99 6.10.8.4. 80 if (isDefineUndef == 1) 81 Diag(MacroNameTok, diag::pp_redef_builtin_macro); 82 else 83 Diag(MacroNameTok, diag::pp_undef_builtin_macro); 84 } else { 85 // Okay, we got a good identifier node. Return it. 86 return; 87 } 88 89 // Invalid macro name, read and discard the rest of the line. Then set the 90 // token kind to tok::eom. 91 MacroNameTok.setKind(tok::eom); 92 return DiscardUntilEndOfDirective(); 93} 94 95/// CheckEndOfDirective - Ensure that the next token is a tok::eom token. If 96/// not, emit a diagnostic and consume up until the eom. 97void Preprocessor::CheckEndOfDirective(const char *DirType) { 98 Token Tmp; 99 // Lex unexpanded tokens: macros might expand to zero tokens, causing us to 100 // miss diagnosing invalid lines. 101 LexUnexpandedToken(Tmp); 102 103 // There should be no tokens after the directive, but we allow them as an 104 // extension. 105 while (Tmp.is(tok::comment)) // Skip comments in -C mode. 106 LexUnexpandedToken(Tmp); 107 108 if (Tmp.isNot(tok::eom)) { 109 Diag(Tmp, diag::ext_pp_extra_tokens_at_eol) << DirType; 110 DiscardUntilEndOfDirective(); 111 } 112} 113 114 115 116/// SkipExcludedConditionalBlock - We just read a #if or related directive and 117/// decided that the subsequent tokens are in the #if'd out portion of the 118/// file. Lex the rest of the file, until we see an #endif. If 119/// FoundNonSkipPortion is true, then we have already emitted code for part of 120/// this #if directive, so #else/#elif blocks should never be entered. If ElseOk 121/// is true, then #else directives are ok, if not, then we have already seen one 122/// so a #else directive is a duplicate. When this returns, the caller can lex 123/// the first valid token. 124void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc, 125 bool FoundNonSkipPortion, 126 bool FoundElse) { 127 ++NumSkipped; 128 assert(CurTokenLexer == 0 && CurPPLexer && "Lexing a macro, not a file?"); 129 130 CurPPLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false, 131 FoundNonSkipPortion, FoundElse); 132 133 if (CurPTHLexer) { 134 PTHSkipExcludedConditionalBlock(); 135 return; 136 } 137 138 // Enter raw mode to disable identifier lookup (and thus macro expansion), 139 // disabling warnings, etc. 140 CurPPLexer->LexingRawMode = true; 141 Token Tok; 142 while (1) { 143 if (CurLexer) 144 CurLexer->Lex(Tok); 145 else 146 CurPTHLexer->Lex(Tok); 147 148 // If this is the end of the buffer, we have an error. 149 if (Tok.is(tok::eof)) { 150 // Emit errors for each unterminated conditional on the stack, including 151 // the current one. 152 while (!CurPPLexer->ConditionalStack.empty()) { 153 Diag(CurPPLexer->ConditionalStack.back().IfLoc, 154 diag::err_pp_unterminated_conditional); 155 CurPPLexer->ConditionalStack.pop_back(); 156 } 157 158 // Just return and let the caller lex after this #include. 159 break; 160 } 161 162 // If this token is not a preprocessor directive, just skip it. 163 if (Tok.isNot(tok::hash) || !Tok.isAtStartOfLine()) 164 continue; 165 166 // We just parsed a # character at the start of a line, so we're in 167 // directive mode. Tell the lexer this so any newlines we see will be 168 // converted into an EOM token (this terminates the macro). 169 CurPPLexer->ParsingPreprocessorDirective = true; 170 if (CurLexer) CurLexer->SetCommentRetentionState(false); 171 172 173 // Read the next token, the directive flavor. 174 LexUnexpandedToken(Tok); 175 176 // If this isn't an identifier directive (e.g. is "# 1\n" or "#\n", or 177 // something bogus), skip it. 178 if (Tok.isNot(tok::identifier)) { 179 CurPPLexer->ParsingPreprocessorDirective = false; 180 // Restore comment saving mode. 181 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments); 182 continue; 183 } 184 185 // If the first letter isn't i or e, it isn't intesting to us. We know that 186 // this is safe in the face of spelling differences, because there is no way 187 // to spell an i/e in a strange way that is another letter. Skipping this 188 // allows us to avoid looking up the identifier info for #define/#undef and 189 // other common directives. 190 const char *RawCharData = SourceMgr.getCharacterData(Tok.getLocation()); 191 char FirstChar = RawCharData[0]; 192 if (FirstChar >= 'a' && FirstChar <= 'z' && 193 FirstChar != 'i' && FirstChar != 'e') { 194 CurPPLexer->ParsingPreprocessorDirective = false; 195 // Restore comment saving mode. 196 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments); 197 continue; 198 } 199 200 // Get the identifier name without trigraphs or embedded newlines. Note 201 // that we can't use Tok.getIdentifierInfo() because its lookup is disabled 202 // when skipping. 203 // TODO: could do this with zero copies in the no-clean case by using 204 // strncmp below. 205 char Directive[20]; 206 unsigned IdLen; 207 if (!Tok.needsCleaning() && Tok.getLength() < 20) { 208 IdLen = Tok.getLength(); 209 memcpy(Directive, RawCharData, IdLen); 210 Directive[IdLen] = 0; 211 } else { 212 std::string DirectiveStr = getSpelling(Tok); 213 IdLen = DirectiveStr.size(); 214 if (IdLen >= 20) { 215 CurPPLexer->ParsingPreprocessorDirective = false; 216 // Restore comment saving mode. 217 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments); 218 continue; 219 } 220 memcpy(Directive, &DirectiveStr[0], IdLen); 221 Directive[IdLen] = 0; 222 FirstChar = Directive[0]; 223 } 224 225 if (FirstChar == 'i' && Directive[1] == 'f') { 226 if ((IdLen == 2) || // "if" 227 (IdLen == 5 && !strcmp(Directive+2, "def")) || // "ifdef" 228 (IdLen == 6 && !strcmp(Directive+2, "ndef"))) { // "ifndef" 229 // We know the entire #if/#ifdef/#ifndef block will be skipped, don't 230 // bother parsing the condition. 231 DiscardUntilEndOfDirective(); 232 CurPPLexer->pushConditionalLevel(Tok.getLocation(), /*wasskipping*/true, 233 /*foundnonskip*/false, 234 /*fnddelse*/false); 235 } 236 } else if (FirstChar == 'e') { 237 if (IdLen == 5 && !strcmp(Directive+1, "ndif")) { // "endif" 238 CheckEndOfDirective("#endif"); 239 PPConditionalInfo CondInfo; 240 CondInfo.WasSkipping = true; // Silence bogus warning. 241 bool InCond = CurPPLexer->popConditionalLevel(CondInfo); 242 InCond = InCond; // Silence warning in no-asserts mode. 243 assert(!InCond && "Can't be skipping if not in a conditional!"); 244 245 // If we popped the outermost skipping block, we're done skipping! 246 if (!CondInfo.WasSkipping) 247 break; 248 } else if (IdLen == 4 && !strcmp(Directive+1, "lse")) { // "else". 249 // #else directive in a skipping conditional. If not in some other 250 // skipping conditional, and if #else hasn't already been seen, enter it 251 // as a non-skipping conditional. 252 CheckEndOfDirective("#else"); 253 PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel(); 254 255 // If this is a #else with a #else before it, report the error. 256 if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_else_after_else); 257 258 // Note that we've seen a #else in this conditional. 259 CondInfo.FoundElse = true; 260 261 // If the conditional is at the top level, and the #if block wasn't 262 // entered, enter the #else block now. 263 if (!CondInfo.WasSkipping && !CondInfo.FoundNonSkip) { 264 CondInfo.FoundNonSkip = true; 265 break; 266 } 267 } else if (IdLen == 4 && !strcmp(Directive+1, "lif")) { // "elif". 268 PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel(); 269 270 bool ShouldEnter; 271 // If this is in a skipping block or if we're already handled this #if 272 // block, don't bother parsing the condition. 273 if (CondInfo.WasSkipping || CondInfo.FoundNonSkip) { 274 DiscardUntilEndOfDirective(); 275 ShouldEnter = false; 276 } else { 277 // Restore the value of LexingRawMode so that identifiers are 278 // looked up, etc, inside the #elif expression. 279 assert(CurPPLexer->LexingRawMode && "We have to be skipping here!"); 280 CurPPLexer->LexingRawMode = false; 281 IdentifierInfo *IfNDefMacro = 0; 282 ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro); 283 CurPPLexer->LexingRawMode = true; 284 } 285 286 // If this is a #elif with a #else before it, report the error. 287 if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_elif_after_else); 288 289 // If this condition is true, enter it! 290 if (ShouldEnter) { 291 CondInfo.FoundNonSkip = true; 292 break; 293 } 294 } 295 } 296 297 CurPPLexer->ParsingPreprocessorDirective = false; 298 // Restore comment saving mode. 299 if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments); 300 } 301 302 // Finally, if we are out of the conditional (saw an #endif or ran off the end 303 // of the file, just stop skipping and return to lexing whatever came after 304 // the #if block. 305 CurPPLexer->LexingRawMode = false; 306} 307 308void Preprocessor::PTHSkipExcludedConditionalBlock() { 309 310 while(1) { 311 assert(CurPTHLexer); 312 assert(CurPTHLexer->LexingRawMode == false); 313 314 // Skip to the next '#else', '#elif', or #endif. 315 if (CurPTHLexer->SkipBlock()) { 316 // We have reached an #endif. Both the '#' and 'endif' tokens 317 // have been consumed by the PTHLexer. Just pop off the condition level. 318 PPConditionalInfo CondInfo; 319 bool InCond = CurPTHLexer->popConditionalLevel(CondInfo); 320 InCond = InCond; // Silence warning in no-asserts mode. 321 assert(!InCond && "Can't be skipping if not in a conditional!"); 322 break; 323 } 324 325 // We have reached a '#else' or '#elif'. Lex the next token to get 326 // the directive flavor. 327 Token Tok; 328 LexUnexpandedToken(Tok); 329 330 // We can actually look up the IdentifierInfo here since we aren't in 331 // raw mode. 332 tok::PPKeywordKind K = Tok.getIdentifierInfo()->getPPKeywordID(); 333 334 if (K == tok::pp_else) { 335 // #else: Enter the else condition. We aren't in a nested condition 336 // since we skip those. We're always in the one matching the last 337 // blocked we skipped. 338 PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel(); 339 // Note that we've seen a #else in this conditional. 340 CondInfo.FoundElse = true; 341 342 // If the #if block wasn't entered then enter the #else block now. 343 if (!CondInfo.FoundNonSkip) { 344 CondInfo.FoundNonSkip = true; 345 346 // Consume the eom token. 347 CurPTHLexer->ParsingPreprocessorDirective = true; 348 LexUnexpandedToken(Tok); 349 assert(Tok.is(tok::eom)); 350 CurPTHLexer->ParsingPreprocessorDirective = false; 351 352 break; 353 } 354 355 // Otherwise skip this block. 356 continue; 357 } 358 359 assert(K == tok::pp_elif); 360 PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel(); 361 362 // If this is a #elif with a #else before it, report the error. 363 if (CondInfo.FoundElse) 364 Diag(Tok, diag::pp_err_elif_after_else); 365 366 // If this is in a skipping block or if we're already handled this #if 367 // block, don't bother parsing the condition. We just skip this block. 368 if (CondInfo.FoundNonSkip) 369 continue; 370 371 // Evaluate the condition of the #elif. 372 IdentifierInfo *IfNDefMacro = 0; 373 CurPTHLexer->ParsingPreprocessorDirective = true; 374 bool ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro); 375 CurPTHLexer->ParsingPreprocessorDirective = false; 376 377 // If this condition is true, enter it! 378 if (ShouldEnter) { 379 CondInfo.FoundNonSkip = true; 380 break; 381 } 382 383 // Otherwise, skip this block and go to the next one. 384 continue; 385 } 386} 387 388/// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 389/// return null on failure. isAngled indicates whether the file reference is 390/// for system #include's or not (i.e. using <> instead of ""). 391const FileEntry *Preprocessor::LookupFile(const char *FilenameStart, 392 const char *FilenameEnd, 393 bool isAngled, 394 const DirectoryLookup *FromDir, 395 const DirectoryLookup *&CurDir) { 396 // If the header lookup mechanism may be relative to the current file, pass in 397 // info about where the current file is. 398 const FileEntry *CurFileEnt = 0; 399 if (!FromDir) { 400 FileID FID = getCurrentFileLexer()->getFileID(); 401 CurFileEnt = SourceMgr.getFileEntryForID(FID); 402 403 // If there is no file entry associated with this file, it must be the 404 // predefines buffer. Any other file is not lexed with a normal lexer, so 405 // it won't be scanned for preprocessor directives. If we have the 406 // predefines buffer, resolve #include references (which come from the 407 // -include command line argument) as if they came from the main file, this 408 // affects file lookup etc. 409 if (CurFileEnt == 0) { 410 FID = SourceMgr.getMainFileID(); 411 CurFileEnt = SourceMgr.getFileEntryForID(FID); 412 } 413 } 414 415 // Do a standard file entry lookup. 416 CurDir = CurDirLookup; 417 const FileEntry *FE = 418 HeaderInfo.LookupFile(FilenameStart, FilenameEnd, 419 isAngled, FromDir, CurDir, CurFileEnt); 420 if (FE) return FE; 421 422 // Otherwise, see if this is a subframework header. If so, this is relative 423 // to one of the headers on the #include stack. Walk the list of the current 424 // headers on the #include stack and pass them to HeaderInfo. 425 if (IsFileLexer()) { 426 if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID()))) 427 if ((FE = HeaderInfo.LookupSubframeworkHeader(FilenameStart, FilenameEnd, 428 CurFileEnt))) 429 return FE; 430 } 431 432 for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) { 433 IncludeStackInfo &ISEntry = IncludeMacroStack[e-i-1]; 434 if (IsFileLexer(ISEntry)) { 435 if ((CurFileEnt = 436 SourceMgr.getFileEntryForID(ISEntry.ThePPLexer->getFileID()))) 437 if ((FE = HeaderInfo.LookupSubframeworkHeader(FilenameStart, 438 FilenameEnd, CurFileEnt))) 439 return FE; 440 } 441 } 442 443 // Otherwise, we really couldn't find the file. 444 return 0; 445} 446 447 448//===----------------------------------------------------------------------===// 449// Preprocessor Directive Handling. 450//===----------------------------------------------------------------------===// 451 452/// HandleDirective - This callback is invoked when the lexer sees a # token 453/// at the start of a line. This consumes the directive, modifies the 454/// lexer/preprocessor state, and advances the lexer(s) so that the next token 455/// read is the correct one. 456void Preprocessor::HandleDirective(Token &Result) { 457 // FIXME: Traditional: # with whitespace before it not recognized by K&R? 458 459 // We just parsed a # character at the start of a line, so we're in directive 460 // mode. Tell the lexer this so any newlines we see will be converted into an 461 // EOM token (which terminates the directive). 462 CurPPLexer->ParsingPreprocessorDirective = true; 463 464 ++NumDirectives; 465 466 // We are about to read a token. For the multiple-include optimization FA to 467 // work, we have to remember if we had read any tokens *before* this 468 // pp-directive. 469 bool ReadAnyTokensBeforeDirective = CurPPLexer->MIOpt.getHasReadAnyTokensVal(); 470 471 // Read the next token, the directive flavor. This isn't expanded due to 472 // C99 6.10.3p8. 473 LexUnexpandedToken(Result); 474 475 // C99 6.10.3p11: Is this preprocessor directive in macro invocation? e.g.: 476 // #define A(x) #x 477 // A(abc 478 // #warning blah 479 // def) 480 // If so, the user is relying on non-portable behavior, emit a diagnostic. 481 if (InMacroArgs) 482 Diag(Result, diag::ext_embedded_directive); 483 484TryAgain: 485 switch (Result.getKind()) { 486 case tok::eom: 487 return; // null directive. 488 case tok::comment: 489 // Handle stuff like "# /*foo*/ define X" in -E -C mode. 490 LexUnexpandedToken(Result); 491 goto TryAgain; 492 493 case tok::numeric_constant: // # 7 GNU line marker directive. 494 return HandleDigitDirective(Result); 495 default: 496 IdentifierInfo *II = Result.getIdentifierInfo(); 497 if (II == 0) break; // Not an identifier. 498 499 // Ask what the preprocessor keyword ID is. 500 switch (II->getPPKeywordID()) { 501 default: break; 502 // C99 6.10.1 - Conditional Inclusion. 503 case tok::pp_if: 504 return HandleIfDirective(Result, ReadAnyTokensBeforeDirective); 505 case tok::pp_ifdef: 506 return HandleIfdefDirective(Result, false, true/*not valid for miopt*/); 507 case tok::pp_ifndef: 508 return HandleIfdefDirective(Result, true, ReadAnyTokensBeforeDirective); 509 case tok::pp_elif: 510 return HandleElifDirective(Result); 511 case tok::pp_else: 512 return HandleElseDirective(Result); 513 case tok::pp_endif: 514 return HandleEndifDirective(Result); 515 516 // C99 6.10.2 - Source File Inclusion. 517 case tok::pp_include: 518 return HandleIncludeDirective(Result); // Handle #include. 519 520 // C99 6.10.3 - Macro Replacement. 521 case tok::pp_define: 522 return HandleDefineDirective(Result); 523 case tok::pp_undef: 524 return HandleUndefDirective(Result); 525 526 // C99 6.10.4 - Line Control. 527 case tok::pp_line: 528 return HandleLineDirective(Result); 529 530 // C99 6.10.5 - Error Directive. 531 case tok::pp_error: 532 return HandleUserDiagnosticDirective(Result, false); 533 534 // C99 6.10.6 - Pragma Directive. 535 case tok::pp_pragma: 536 return HandlePragmaDirective(); 537 538 // GNU Extensions. 539 case tok::pp_import: 540 return HandleImportDirective(Result); 541 case tok::pp_include_next: 542 return HandleIncludeNextDirective(Result); 543 544 case tok::pp_warning: 545 Diag(Result, diag::ext_pp_warning_directive); 546 return HandleUserDiagnosticDirective(Result, true); 547 case tok::pp_ident: 548 return HandleIdentSCCSDirective(Result); 549 case tok::pp_sccs: 550 return HandleIdentSCCSDirective(Result); 551 case tok::pp_assert: 552 //isExtension = true; // FIXME: implement #assert 553 break; 554 case tok::pp_unassert: 555 //isExtension = true; // FIXME: implement #unassert 556 break; 557 } 558 break; 559 } 560 561 // If we reached here, the preprocessing token is not valid! 562 Diag(Result, diag::err_pp_invalid_directive); 563 564 // Read the rest of the PP line. 565 DiscardUntilEndOfDirective(); 566 567 // Okay, we're done parsing the directive. 568} 569 570/// GetLineValue - Convert a numeric token into an unsigned value, emitting 571/// Diagnostic DiagID if it is invalid, and returning the value in Val. 572static bool GetLineValue(Token &DigitTok, unsigned &Val, 573 unsigned DiagID, Preprocessor &PP) { 574 if (DigitTok.isNot(tok::numeric_constant)) { 575 PP.Diag(DigitTok, DiagID); 576 577 if (DigitTok.isNot(tok::eom)) 578 PP.DiscardUntilEndOfDirective(); 579 return true; 580 } 581 582 llvm::SmallString<64> IntegerBuffer; 583 IntegerBuffer.resize(DigitTok.getLength()); 584 const char *DigitTokBegin = &IntegerBuffer[0]; 585 unsigned ActualLength = PP.getSpelling(DigitTok, DigitTokBegin); 586 NumericLiteralParser Literal(DigitTokBegin, DigitTokBegin+ActualLength, 587 DigitTok.getLocation(), PP); 588 if (Literal.hadError) 589 return true; // Error already emitted. 590 591 if (Literal.isFloatingLiteral() || Literal.isImaginary) { 592 PP.Diag(DigitTok, DiagID); 593 return true; 594 } 595 596 // Parse the integer literal into Result. 597 llvm::APInt APVal(32, 0); 598 if (Literal.GetIntegerValue(APVal)) { 599 // Overflow parsing integer literal. 600 PP.Diag(DigitTok, DiagID); 601 return true; 602 } 603 Val = APVal.getZExtValue(); 604 605 // Reject 0, this is needed both by #line numbers and flags. 606 if (Val == 0) { 607 PP.Diag(DigitTok, DiagID); 608 PP.DiscardUntilEndOfDirective(); 609 return true; 610 } 611 612 return false; 613} 614 615/// HandleLineDirective - Handle #line directive: C99 6.10.4. The two 616/// acceptable forms are: 617/// # line digit-sequence 618/// # line digit-sequence "s-char-sequence" 619void Preprocessor::HandleLineDirective(Token &Tok) { 620 // Read the line # and string argument. Per C99 6.10.4p5, these tokens are 621 // expanded. 622 Token DigitTok; 623 Lex(DigitTok); 624 625 // Validate the number and convert it to an unsigned. 626 unsigned LineNo; 627 if (GetLineValue(DigitTok, LineNo, diag::err_pp_line_requires_integer, *this)) 628 return; 629 630 // Enforce C99 6.10.4p3: "The digit sequence shall not specify ... a 631 // number greater than 2147483647". C90 requires that the line # be <= 32767. 632 unsigned LineLimit = Features.C99 ? 2147483648U : 32768U; 633 if (LineNo >= LineLimit) 634 Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit; 635 636 int FilenameID = -1; 637 Token StrTok; 638 Lex(StrTok); 639 640 // If the StrTok is "eom", then it wasn't present. Otherwise, it must be a 641 // string followed by eom. 642 if (StrTok.is(tok::eom)) 643 ; // ok 644 else if (StrTok.isNot(tok::string_literal)) { 645 Diag(StrTok, diag::err_pp_line_invalid_filename); 646 DiscardUntilEndOfDirective(); 647 return; 648 } else { 649 // Parse and validate the string, converting it into a unique ID. 650 StringLiteralParser Literal(&StrTok, 1, *this); 651 assert(!Literal.AnyWide && "Didn't allow wide strings in"); 652 if (Literal.hadError) 653 return DiscardUntilEndOfDirective(); 654 if (Literal.Pascal) { 655 Diag(StrTok, diag::err_pp_linemarker_invalid_filename); 656 return DiscardUntilEndOfDirective(); 657 } 658 FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString(), 659 Literal.GetStringLength()); 660 661 // Verify that there is nothing after the string, other than EOM. 662 CheckEndOfDirective("#line"); 663 } 664 665 SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID); 666} 667 668/// ReadLineMarkerFlags - Parse and validate any flags at the end of a GNU line 669/// marker directive. 670static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit, 671 bool &IsSystemHeader, bool &IsExternCHeader, 672 Preprocessor &PP) { 673 unsigned FlagVal; 674 Token FlagTok; 675 PP.Lex(FlagTok); 676 if (FlagTok.is(tok::eom)) return false; 677 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP)) 678 return true; 679 680 if (FlagVal == 1) { 681 IsFileEntry = true; 682 683 PP.Lex(FlagTok); 684 if (FlagTok.is(tok::eom)) return false; 685 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP)) 686 return true; 687 } else if (FlagVal == 2) { 688 IsFileExit = true; 689 690 SourceManager &SM = PP.getSourceManager(); 691 // If we are leaving the current presumed file, check to make sure the 692 // presumed include stack isn't empty! 693 FileID CurFileID = 694 SM.getDecomposedInstantiationLoc(FlagTok.getLocation()).first; 695 PresumedLoc PLoc = SM.getPresumedLoc(FlagTok.getLocation()); 696 697 // If there is no include loc (main file) or if the include loc is in a 698 // different physical file, then we aren't in a "1" line marker flag region. 699 SourceLocation IncLoc = PLoc.getIncludeLoc(); 700 if (IncLoc.isInvalid() || 701 SM.getDecomposedInstantiationLoc(IncLoc).first != CurFileID) { 702 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_pop); 703 PP.DiscardUntilEndOfDirective(); 704 return true; 705 } 706 707 PP.Lex(FlagTok); 708 if (FlagTok.is(tok::eom)) return false; 709 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP)) 710 return true; 711 } 712 713 // We must have 3 if there are still flags. 714 if (FlagVal != 3) { 715 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); 716 PP.DiscardUntilEndOfDirective(); 717 return true; 718 } 719 720 IsSystemHeader = true; 721 722 PP.Lex(FlagTok); 723 if (FlagTok.is(tok::eom)) return false; 724 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP)) 725 return true; 726 727 // We must have 4 if there is yet another flag. 728 if (FlagVal != 4) { 729 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); 730 PP.DiscardUntilEndOfDirective(); 731 return true; 732 } 733 734 IsExternCHeader = true; 735 736 PP.Lex(FlagTok); 737 if (FlagTok.is(tok::eom)) return false; 738 739 // There are no more valid flags here. 740 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); 741 PP.DiscardUntilEndOfDirective(); 742 return true; 743} 744 745/// HandleDigitDirective - Handle a GNU line marker directive, whose syntax is 746/// one of the following forms: 747/// 748/// # 42 749/// # 42 "file" ('1' | '2')? 750/// # 42 "file" ('1' | '2')? '3' '4'? 751/// 752void Preprocessor::HandleDigitDirective(Token &DigitTok) { 753 // Validate the number and convert it to an unsigned. GNU does not have a 754 // line # limit other than it fit in 32-bits. 755 unsigned LineNo; 756 if (GetLineValue(DigitTok, LineNo, diag::err_pp_linemarker_requires_integer, 757 *this)) 758 return; 759 760 Token StrTok; 761 Lex(StrTok); 762 763 bool IsFileEntry = false, IsFileExit = false; 764 bool IsSystemHeader = false, IsExternCHeader = false; 765 int FilenameID = -1; 766 767 // If the StrTok is "eom", then it wasn't present. Otherwise, it must be a 768 // string followed by eom. 769 if (StrTok.is(tok::eom)) 770 ; // ok 771 else if (StrTok.isNot(tok::string_literal)) { 772 Diag(StrTok, diag::err_pp_linemarker_invalid_filename); 773 return DiscardUntilEndOfDirective(); 774 } else { 775 // Parse and validate the string, converting it into a unique ID. 776 StringLiteralParser Literal(&StrTok, 1, *this); 777 assert(!Literal.AnyWide && "Didn't allow wide strings in"); 778 if (Literal.hadError) 779 return DiscardUntilEndOfDirective(); 780 if (Literal.Pascal) { 781 Diag(StrTok, diag::err_pp_linemarker_invalid_filename); 782 return DiscardUntilEndOfDirective(); 783 } 784 FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString(), 785 Literal.GetStringLength()); 786 787 // If a filename was present, read any flags that are present. 788 if (ReadLineMarkerFlags(IsFileEntry, IsFileExit, 789 IsSystemHeader, IsExternCHeader, *this)) 790 return; 791 } 792 793 // Create a line note with this information. 794 SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID, 795 IsFileEntry, IsFileExit, 796 IsSystemHeader, IsExternCHeader); 797} 798 799 800/// HandleUserDiagnosticDirective - Handle a #warning or #error directive. 801/// 802void Preprocessor::HandleUserDiagnosticDirective(Token &Tok, 803 bool isWarning) { 804 // PTH doesn't emit #warning or #error directives. 805 if (CurPTHLexer) 806 return CurPTHLexer->DiscardToEndOfLine(); 807 808 // Read the rest of the line raw. We do this because we don't want macros 809 // to be expanded and we don't require that the tokens be valid preprocessing 810 // tokens. For example, this is allowed: "#warning ` 'foo". GCC does 811 // collapse multiple consequtive white space between tokens, but this isn't 812 // specified by the standard. 813 std::string Message = CurLexer->ReadToEndOfLine(); 814 if (isWarning) 815 Diag(Tok, diag::pp_hash_warning) << Message; 816 else 817 Diag(Tok, diag::err_pp_hash_error) << Message; 818} 819 820/// HandleIdentSCCSDirective - Handle a #ident/#sccs directive. 821/// 822void Preprocessor::HandleIdentSCCSDirective(Token &Tok) { 823 // Yes, this directive is an extension. 824 Diag(Tok, diag::ext_pp_ident_directive); 825 826 // Read the string argument. 827 Token StrTok; 828 Lex(StrTok); 829 830 // If the token kind isn't a string, it's a malformed directive. 831 if (StrTok.isNot(tok::string_literal) && 832 StrTok.isNot(tok::wide_string_literal)) { 833 Diag(StrTok, diag::err_pp_malformed_ident); 834 if (StrTok.isNot(tok::eom)) 835 DiscardUntilEndOfDirective(); 836 return; 837 } 838 839 // Verify that there is nothing after the string, other than EOM. 840 CheckEndOfDirective("#ident"); 841 842 if (Callbacks) 843 Callbacks->Ident(Tok.getLocation(), getSpelling(StrTok)); 844} 845 846//===----------------------------------------------------------------------===// 847// Preprocessor Include Directive Handling. 848//===----------------------------------------------------------------------===// 849 850/// GetIncludeFilenameSpelling - Turn the specified lexer token into a fully 851/// checked and spelled filename, e.g. as an operand of #include. This returns 852/// true if the input filename was in <>'s or false if it were in ""'s. The 853/// caller is expected to provide a buffer that is large enough to hold the 854/// spelling of the filename, but is also expected to handle the case when 855/// this method decides to use a different buffer. 856bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc, 857 const char *&BufStart, 858 const char *&BufEnd) { 859 // Get the text form of the filename. 860 assert(BufStart != BufEnd && "Can't have tokens with empty spellings!"); 861 862 // Make sure the filename is <x> or "x". 863 bool isAngled; 864 if (BufStart[0] == '<') { 865 if (BufEnd[-1] != '>') { 866 Diag(Loc, diag::err_pp_expects_filename); 867 BufStart = 0; 868 return true; 869 } 870 isAngled = true; 871 } else if (BufStart[0] == '"') { 872 if (BufEnd[-1] != '"') { 873 Diag(Loc, diag::err_pp_expects_filename); 874 BufStart = 0; 875 return true; 876 } 877 isAngled = false; 878 } else { 879 Diag(Loc, diag::err_pp_expects_filename); 880 BufStart = 0; 881 return true; 882 } 883 884 // Diagnose #include "" as invalid. 885 if (BufEnd-BufStart <= 2) { 886 Diag(Loc, diag::err_pp_empty_filename); 887 BufStart = 0; 888 return ""; 889 } 890 891 // Skip the brackets. 892 ++BufStart; 893 --BufEnd; 894 return isAngled; 895} 896 897/// ConcatenateIncludeName - Handle cases where the #include name is expanded 898/// from a macro as multiple tokens, which need to be glued together. This 899/// occurs for code like: 900/// #define FOO <a/b.h> 901/// #include FOO 902/// because in this case, "<a/b.h>" is returned as 7 tokens, not one. 903/// 904/// This code concatenates and consumes tokens up to the '>' token. It returns 905/// false if the > was found, otherwise it returns true if it finds and consumes 906/// the EOM marker. 907static bool ConcatenateIncludeName(llvm::SmallVector<char, 128> &FilenameBuffer, 908 Preprocessor &PP) { 909 Token CurTok; 910 911 PP.Lex(CurTok); 912 while (CurTok.isNot(tok::eom)) { 913 // Append the spelling of this token to the buffer. If there was a space 914 // before it, add it now. 915 if (CurTok.hasLeadingSpace()) 916 FilenameBuffer.push_back(' '); 917 918 // Get the spelling of the token, directly into FilenameBuffer if possible. 919 unsigned PreAppendSize = FilenameBuffer.size(); 920 FilenameBuffer.resize(PreAppendSize+CurTok.getLength()); 921 922 const char *BufPtr = &FilenameBuffer[PreAppendSize]; 923 unsigned ActualLen = PP.getSpelling(CurTok, BufPtr); 924 925 // If the token was spelled somewhere else, copy it into FilenameBuffer. 926 if (BufPtr != &FilenameBuffer[PreAppendSize]) 927 memcpy(&FilenameBuffer[PreAppendSize], BufPtr, ActualLen); 928 929 // Resize FilenameBuffer to the correct size. 930 if (CurTok.getLength() != ActualLen) 931 FilenameBuffer.resize(PreAppendSize+ActualLen); 932 933 // If we found the '>' marker, return success. 934 if (CurTok.is(tok::greater)) 935 return false; 936 937 PP.Lex(CurTok); 938 } 939 940 // If we hit the eom marker, emit an error and return true so that the caller 941 // knows the EOM has been read. 942 PP.Diag(CurTok.getLocation(), diag::err_pp_expects_filename); 943 return true; 944} 945 946/// HandleIncludeDirective - The "#include" tokens have just been read, read the 947/// file to be included from the lexer, then include it! This is a common 948/// routine with functionality shared between #include, #include_next and 949/// #import. LookupFrom is set when this is a #include_next directive, it 950/// specifies the file to start searching from. 951void Preprocessor::HandleIncludeDirective(Token &IncludeTok, 952 const DirectoryLookup *LookupFrom, 953 bool isImport) { 954 955 Token FilenameTok; 956 CurPPLexer->LexIncludeFilename(FilenameTok); 957 958 // Reserve a buffer to get the spelling. 959 llvm::SmallVector<char, 128> FilenameBuffer; 960 const char *FilenameStart, *FilenameEnd; 961 962 switch (FilenameTok.getKind()) { 963 case tok::eom: 964 // If the token kind is EOM, the error has already been diagnosed. 965 return; 966 967 case tok::angle_string_literal: 968 case tok::string_literal: { 969 FilenameBuffer.resize(FilenameTok.getLength()); 970 FilenameStart = &FilenameBuffer[0]; 971 unsigned Len = getSpelling(FilenameTok, FilenameStart); 972 FilenameEnd = FilenameStart+Len; 973 break; 974 } 975 976 case tok::less: 977 // This could be a <foo/bar.h> file coming from a macro expansion. In this 978 // case, glue the tokens together into FilenameBuffer and interpret those. 979 FilenameBuffer.push_back('<'); 980 if (ConcatenateIncludeName(FilenameBuffer, *this)) 981 return; // Found <eom> but no ">"? Diagnostic already emitted. 982 FilenameStart = &FilenameBuffer[0]; 983 FilenameEnd = &FilenameBuffer[FilenameBuffer.size()]; 984 break; 985 default: 986 Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename); 987 DiscardUntilEndOfDirective(); 988 return; 989 } 990 991 bool isAngled = GetIncludeFilenameSpelling(FilenameTok.getLocation(), 992 FilenameStart, FilenameEnd); 993 // If GetIncludeFilenameSpelling set the start ptr to null, there was an 994 // error. 995 if (FilenameStart == 0) { 996 DiscardUntilEndOfDirective(); 997 return; 998 } 999 1000 // Verify that there is nothing after the filename, other than EOM. Use the 1001 // preprocessor to lex this in case lexing the filename entered a macro. 1002 CheckEndOfDirective("#include"); 1003 1004 // Check that we don't have infinite #include recursion. 1005 if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1) { 1006 Diag(FilenameTok, diag::err_pp_include_too_deep); 1007 return; 1008 } 1009 1010 // Search include directories. 1011 const DirectoryLookup *CurDir; 1012 const FileEntry *File = LookupFile(FilenameStart, FilenameEnd, 1013 isAngled, LookupFrom, CurDir); 1014 if (File == 0) { 1015 Diag(FilenameTok, diag::err_pp_file_not_found) 1016 << std::string(FilenameStart, FilenameEnd); 1017 return; 1018 } 1019 1020 // Ask HeaderInfo if we should enter this #include file. If not, #including 1021 // this file will have no effect. 1022 if (!HeaderInfo.ShouldEnterIncludeFile(File, isImport)) 1023 return; 1024 1025 // The #included file will be considered to be a system header if either it is 1026 // in a system include directory, or if the #includer is a system include 1027 // header. 1028 SrcMgr::CharacteristicKind FileCharacter = 1029 std::max(HeaderInfo.getFileDirFlavor(File), 1030 SourceMgr.getFileCharacteristic(FilenameTok.getLocation())); 1031 1032 // Look up the file, create a File ID for it. 1033 FileID FID = SourceMgr.createFileID(File, FilenameTok.getLocation(), 1034 FileCharacter); 1035 if (FID.isInvalid()) { 1036 Diag(FilenameTok, diag::err_pp_file_not_found) 1037 << std::string(FilenameStart, FilenameEnd); 1038 return; 1039 } 1040 1041 // Finally, if all is good, enter the new file! 1042 EnterSourceFile(FID, CurDir); 1043} 1044 1045/// HandleIncludeNextDirective - Implements #include_next. 1046/// 1047void Preprocessor::HandleIncludeNextDirective(Token &IncludeNextTok) { 1048 Diag(IncludeNextTok, diag::ext_pp_include_next_directive); 1049 1050 // #include_next is like #include, except that we start searching after 1051 // the current found directory. If we can't do this, issue a 1052 // diagnostic. 1053 const DirectoryLookup *Lookup = CurDirLookup; 1054 if (isInPrimaryFile()) { 1055 Lookup = 0; 1056 Diag(IncludeNextTok, diag::pp_include_next_in_primary); 1057 } else if (Lookup == 0) { 1058 Diag(IncludeNextTok, diag::pp_include_next_absolute_path); 1059 } else { 1060 // Start looking up in the next directory. 1061 ++Lookup; 1062 } 1063 1064 return HandleIncludeDirective(IncludeNextTok, Lookup); 1065} 1066 1067/// HandleImportDirective - Implements #import. 1068/// 1069void Preprocessor::HandleImportDirective(Token &ImportTok) { 1070 Diag(ImportTok, diag::ext_pp_import_directive); 1071 1072 return HandleIncludeDirective(ImportTok, 0, true); 1073} 1074 1075//===----------------------------------------------------------------------===// 1076// Preprocessor Macro Directive Handling. 1077//===----------------------------------------------------------------------===// 1078 1079/// ReadMacroDefinitionArgList - The ( starting an argument list of a macro 1080/// definition has just been read. Lex the rest of the arguments and the 1081/// closing ), updating MI with what we learn. Return true if an error occurs 1082/// parsing the arg list. 1083bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) { 1084 llvm::SmallVector<IdentifierInfo*, 32> Arguments; 1085 1086 Token Tok; 1087 while (1) { 1088 LexUnexpandedToken(Tok); 1089 switch (Tok.getKind()) { 1090 case tok::r_paren: 1091 // Found the end of the argument list. 1092 if (Arguments.empty()) { // #define FOO() 1093 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1094 return false; 1095 } 1096 // Otherwise we have #define FOO(A,) 1097 Diag(Tok, diag::err_pp_expected_ident_in_arg_list); 1098 return true; 1099 case tok::ellipsis: // #define X(... -> C99 varargs 1100 // Warn if use of C99 feature in non-C99 mode. 1101 if (!Features.C99) Diag(Tok, diag::ext_variadic_macro); 1102 1103 // Lex the token after the identifier. 1104 LexUnexpandedToken(Tok); 1105 if (Tok.isNot(tok::r_paren)) { 1106 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); 1107 return true; 1108 } 1109 // Add the __VA_ARGS__ identifier as an argument. 1110 Arguments.push_back(Ident__VA_ARGS__); 1111 MI->setIsC99Varargs(); 1112 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1113 return false; 1114 case tok::eom: // #define X( 1115 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); 1116 return true; 1117 default: 1118 // Handle keywords and identifiers here to accept things like 1119 // #define Foo(for) for. 1120 IdentifierInfo *II = Tok.getIdentifierInfo(); 1121 if (II == 0) { 1122 // #define X(1 1123 Diag(Tok, diag::err_pp_invalid_tok_in_arg_list); 1124 return true; 1125 } 1126 1127 // If this is already used as an argument, it is used multiple times (e.g. 1128 // #define X(A,A. 1129 if (std::find(Arguments.begin(), Arguments.end(), II) != 1130 Arguments.end()) { // C99 6.10.3p6 1131 Diag(Tok, diag::err_pp_duplicate_name_in_arg_list) << II; 1132 return true; 1133 } 1134 1135 // Add the argument to the macro info. 1136 Arguments.push_back(II); 1137 1138 // Lex the token after the identifier. 1139 LexUnexpandedToken(Tok); 1140 1141 switch (Tok.getKind()) { 1142 default: // #define X(A B 1143 Diag(Tok, diag::err_pp_expected_comma_in_arg_list); 1144 return true; 1145 case tok::r_paren: // #define X(A) 1146 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1147 return false; 1148 case tok::comma: // #define X(A, 1149 break; 1150 case tok::ellipsis: // #define X(A... -> GCC extension 1151 // Diagnose extension. 1152 Diag(Tok, diag::ext_named_variadic_macro); 1153 1154 // Lex the token after the identifier. 1155 LexUnexpandedToken(Tok); 1156 if (Tok.isNot(tok::r_paren)) { 1157 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); 1158 return true; 1159 } 1160 1161 MI->setIsGNUVarargs(); 1162 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1163 return false; 1164 } 1165 } 1166 } 1167} 1168 1169/// HandleDefineDirective - Implements #define. This consumes the entire macro 1170/// line then lets the caller lex the next real token. 1171void Preprocessor::HandleDefineDirective(Token &DefineTok) { 1172 ++NumDefined; 1173 1174 Token MacroNameTok; 1175 ReadMacroName(MacroNameTok, 1); 1176 1177 // Error reading macro name? If so, diagnostic already issued. 1178 if (MacroNameTok.is(tok::eom)) 1179 return; 1180 1181 // If we are supposed to keep comments in #defines, reenable comment saving 1182 // mode. 1183 if (CurLexer) CurLexer->SetCommentRetentionState(KeepMacroComments); 1184 1185 // Create the new macro. 1186 MacroInfo *MI = AllocateMacroInfo(MacroNameTok.getLocation()); 1187 1188 Token Tok; 1189 LexUnexpandedToken(Tok); 1190 1191 // If this is a function-like macro definition, parse the argument list, 1192 // marking each of the identifiers as being used as macro arguments. Also, 1193 // check other constraints on the first token of the macro body. 1194 if (Tok.is(tok::eom)) { 1195 // If there is no body to this macro, we have no special handling here. 1196 } else if (Tok.is(tok::l_paren) && !Tok.hasLeadingSpace()) { 1197 // This is a function-like macro definition. Read the argument list. 1198 MI->setIsFunctionLike(); 1199 if (ReadMacroDefinitionArgList(MI)) { 1200 // Forget about MI. 1201 ReleaseMacroInfo(MI); 1202 // Throw away the rest of the line. 1203 if (CurPPLexer->ParsingPreprocessorDirective) 1204 DiscardUntilEndOfDirective(); 1205 return; 1206 } 1207 1208 // Read the first token after the arg list for down below. 1209 LexUnexpandedToken(Tok); 1210 } else if (!Tok.hasLeadingSpace()) { 1211 // C99 requires whitespace between the macro definition and the body. Emit 1212 // a diagnostic for something like "#define X+". 1213 if (Features.C99) { 1214 Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name); 1215 } else { 1216 // FIXME: C90/C++ do not get this diagnostic, but it does get a similar 1217 // one in some cases! 1218 } 1219 } else { 1220 // This is a normal token with leading space. Clear the leading space 1221 // marker on the first token to get proper expansion. 1222 Tok.clearFlag(Token::LeadingSpace); 1223 } 1224 1225 // If this is a definition of a variadic C99 function-like macro, not using 1226 // the GNU named varargs extension, enabled __VA_ARGS__. 1227 1228 // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro. 1229 // This gets unpoisoned where it is allowed. 1230 assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned!"); 1231 if (MI->isC99Varargs()) 1232 Ident__VA_ARGS__->setIsPoisoned(false); 1233 1234 // Read the rest of the macro body. 1235 if (MI->isObjectLike()) { 1236 // Object-like macros are very simple, just read their body. 1237 while (Tok.isNot(tok::eom)) { 1238 MI->AddTokenToBody(Tok); 1239 // Get the next token of the macro. 1240 LexUnexpandedToken(Tok); 1241 } 1242 1243 } else { 1244 // Otherwise, read the body of a function-like macro. This has to validate 1245 // the # (stringize) operator. 1246 while (Tok.isNot(tok::eom)) { 1247 MI->AddTokenToBody(Tok); 1248 1249 // Check C99 6.10.3.2p1: ensure that # operators are followed by macro 1250 // parameters in function-like macro expansions. 1251 if (Tok.isNot(tok::hash)) { 1252 // Get the next token of the macro. 1253 LexUnexpandedToken(Tok); 1254 continue; 1255 } 1256 1257 // Get the next token of the macro. 1258 LexUnexpandedToken(Tok); 1259 1260 // Not a macro arg identifier? 1261 if (!Tok.getIdentifierInfo() || 1262 MI->getArgumentNum(Tok.getIdentifierInfo()) == -1) { 1263 Diag(Tok, diag::err_pp_stringize_not_parameter); 1264 ReleaseMacroInfo(MI); 1265 1266 // Disable __VA_ARGS__ again. 1267 Ident__VA_ARGS__->setIsPoisoned(true); 1268 return; 1269 } 1270 1271 // Things look ok, add the param name token to the macro. 1272 MI->AddTokenToBody(Tok); 1273 1274 // Get the next token of the macro. 1275 LexUnexpandedToken(Tok); 1276 } 1277 } 1278 1279 1280 // Disable __VA_ARGS__ again. 1281 Ident__VA_ARGS__->setIsPoisoned(true); 1282 1283 // Check that there is no paste (##) operator at the begining or end of the 1284 // replacement list. 1285 unsigned NumTokens = MI->getNumTokens(); 1286 if (NumTokens != 0) { 1287 if (MI->getReplacementToken(0).is(tok::hashhash)) { 1288 Diag(MI->getReplacementToken(0), diag::err_paste_at_start); 1289 ReleaseMacroInfo(MI); 1290 return; 1291 } 1292 if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) { 1293 Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end); 1294 ReleaseMacroInfo(MI); 1295 return; 1296 } 1297 } 1298 1299 // If this is the primary source file, remember that this macro hasn't been 1300 // used yet. 1301 if (isInPrimaryFile()) 1302 MI->setIsUsed(false); 1303 1304 // Finally, if this identifier already had a macro defined for it, verify that 1305 // the macro bodies are identical and free the old definition. 1306 if (MacroInfo *OtherMI = getMacroInfo(MacroNameTok.getIdentifierInfo())) { 1307 // It is very common for system headers to have tons of macro redefinitions 1308 // and for warnings to be disabled in system headers. If this is the case, 1309 // then don't bother calling MacroInfo::isIdenticalTo. 1310 if (!Diags.getSuppressSystemWarnings() || 1311 !SourceMgr.isInSystemHeader(DefineTok.getLocation())) { 1312 if (!OtherMI->isUsed()) 1313 Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used); 1314 1315 // Macros must be identical. This means all tokes and whitespace 1316 // separation must be the same. C99 6.10.3.2. 1317 if (!MI->isIdenticalTo(*OtherMI, *this)) { 1318 Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef) 1319 << MacroNameTok.getIdentifierInfo(); 1320 Diag(OtherMI->getDefinitionLoc(), diag::note_previous_definition); 1321 } 1322 } 1323 1324 ReleaseMacroInfo(OtherMI); 1325 } 1326 1327 setMacroInfo(MacroNameTok.getIdentifierInfo(), MI); 1328} 1329 1330/// HandleUndefDirective - Implements #undef. 1331/// 1332void Preprocessor::HandleUndefDirective(Token &UndefTok) { 1333 ++NumUndefined; 1334 1335 Token MacroNameTok; 1336 ReadMacroName(MacroNameTok, 2); 1337 1338 // Error reading macro name? If so, diagnostic already issued. 1339 if (MacroNameTok.is(tok::eom)) 1340 return; 1341 1342 // Check to see if this is the last token on the #undef line. 1343 CheckEndOfDirective("#undef"); 1344 1345 // Okay, we finally have a valid identifier to undef. 1346 MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo()); 1347 1348 // If the macro is not defined, this is a noop undef, just return. 1349 if (MI == 0) return; 1350 1351 if (!MI->isUsed()) 1352 Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used); 1353 1354 // Free macro definition. 1355 ReleaseMacroInfo(MI); 1356 setMacroInfo(MacroNameTok.getIdentifierInfo(), 0); 1357} 1358 1359 1360//===----------------------------------------------------------------------===// 1361// Preprocessor Conditional Directive Handling. 1362//===----------------------------------------------------------------------===// 1363 1364/// HandleIfdefDirective - Implements the #ifdef/#ifndef directive. isIfndef is 1365/// true when this is a #ifndef directive. ReadAnyTokensBeforeDirective is true 1366/// if any tokens have been returned or pp-directives activated before this 1367/// #ifndef has been lexed. 1368/// 1369void Preprocessor::HandleIfdefDirective(Token &Result, bool isIfndef, 1370 bool ReadAnyTokensBeforeDirective) { 1371 ++NumIf; 1372 Token DirectiveTok = Result; 1373 1374 Token MacroNameTok; 1375 ReadMacroName(MacroNameTok); 1376 1377 // Error reading macro name? If so, diagnostic already issued. 1378 if (MacroNameTok.is(tok::eom)) { 1379 // Skip code until we get to #endif. This helps with recovery by not 1380 // emitting an error when the #endif is reached. 1381 SkipExcludedConditionalBlock(DirectiveTok.getLocation(), 1382 /*Foundnonskip*/false, /*FoundElse*/false); 1383 return; 1384 } 1385 1386 // Check to see if this is the last token on the #if[n]def line. 1387 CheckEndOfDirective(isIfndef ? "#ifndef" : "#ifdef"); 1388 1389 if (CurPPLexer->getConditionalStackDepth() == 0) { 1390 // If the start of a top-level #ifdef, inform MIOpt. 1391 if (!ReadAnyTokensBeforeDirective) { 1392 assert(isIfndef && "#ifdef shouldn't reach here"); 1393 CurPPLexer->MIOpt.EnterTopLevelIFNDEF(MacroNameTok.getIdentifierInfo()); 1394 } else 1395 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1396 } 1397 1398 IdentifierInfo *MII = MacroNameTok.getIdentifierInfo(); 1399 MacroInfo *MI = getMacroInfo(MII); 1400 1401 // If there is a macro, process it. 1402 if (MI) // Mark it used. 1403 MI->setIsUsed(true); 1404 1405 // Should we include the stuff contained by this directive? 1406 if (!MI == isIfndef) { 1407 // Yes, remember that we are inside a conditional, then lex the next token. 1408 CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(), /*wasskip*/false, 1409 /*foundnonskip*/true, /*foundelse*/false); 1410 } else { 1411 // No, skip the contents of this block and return the first token after it. 1412 SkipExcludedConditionalBlock(DirectiveTok.getLocation(), 1413 /*Foundnonskip*/false, 1414 /*FoundElse*/false); 1415 } 1416} 1417 1418/// HandleIfDirective - Implements the #if directive. 1419/// 1420void Preprocessor::HandleIfDirective(Token &IfToken, 1421 bool ReadAnyTokensBeforeDirective) { 1422 ++NumIf; 1423 1424 // Parse and evaluation the conditional expression. 1425 IdentifierInfo *IfNDefMacro = 0; 1426 bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro); 1427 1428 1429 // If this condition is equivalent to #ifndef X, and if this is the first 1430 // directive seen, handle it for the multiple-include optimization. 1431 if (CurPPLexer->getConditionalStackDepth() == 0) { 1432 if (!ReadAnyTokensBeforeDirective && IfNDefMacro) 1433 CurPPLexer->MIOpt.EnterTopLevelIFNDEF(IfNDefMacro); 1434 else 1435 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1436 } 1437 1438 // Should we include the stuff contained by this directive? 1439 if (ConditionalTrue) { 1440 // Yes, remember that we are inside a conditional, then lex the next token. 1441 CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false, 1442 /*foundnonskip*/true, /*foundelse*/false); 1443 } else { 1444 // No, skip the contents of this block and return the first token after it. 1445 SkipExcludedConditionalBlock(IfToken.getLocation(), /*Foundnonskip*/false, 1446 /*FoundElse*/false); 1447 } 1448} 1449 1450/// HandleEndifDirective - Implements the #endif directive. 1451/// 1452void Preprocessor::HandleEndifDirective(Token &EndifToken) { 1453 ++NumEndif; 1454 1455 // Check that this is the whole directive. 1456 CheckEndOfDirective("#endif"); 1457 1458 PPConditionalInfo CondInfo; 1459 if (CurPPLexer->popConditionalLevel(CondInfo)) { 1460 // No conditionals on the stack: this is an #endif without an #if. 1461 Diag(EndifToken, diag::err_pp_endif_without_if); 1462 return; 1463 } 1464 1465 // If this the end of a top-level #endif, inform MIOpt. 1466 if (CurPPLexer->getConditionalStackDepth() == 0) 1467 CurPPLexer->MIOpt.ExitTopLevelConditional(); 1468 1469 assert(!CondInfo.WasSkipping && !CurPPLexer->LexingRawMode && 1470 "This code should only be reachable in the non-skipping case!"); 1471} 1472 1473 1474void Preprocessor::HandleElseDirective(Token &Result) { 1475 ++NumElse; 1476 1477 // #else directive in a non-skipping conditional... start skipping. 1478 CheckEndOfDirective("#else"); 1479 1480 PPConditionalInfo CI; 1481 if (CurPPLexer->popConditionalLevel(CI)) { 1482 Diag(Result, diag::pp_err_else_without_if); 1483 return; 1484 } 1485 1486 // If this is a top-level #else, inform the MIOpt. 1487 if (CurPPLexer->getConditionalStackDepth() == 0) 1488 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1489 1490 // If this is a #else with a #else before it, report the error. 1491 if (CI.FoundElse) Diag(Result, diag::pp_err_else_after_else); 1492 1493 // Finally, skip the rest of the contents of this block and return the first 1494 // token after it. 1495 return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, 1496 /*FoundElse*/true); 1497} 1498 1499void Preprocessor::HandleElifDirective(Token &ElifToken) { 1500 ++NumElse; 1501 1502 // #elif directive in a non-skipping conditional... start skipping. 1503 // We don't care what the condition is, because we will always skip it (since 1504 // the block immediately before it was included). 1505 DiscardUntilEndOfDirective(); 1506 1507 PPConditionalInfo CI; 1508 if (CurPPLexer->popConditionalLevel(CI)) { 1509 Diag(ElifToken, diag::pp_err_elif_without_if); 1510 return; 1511 } 1512 1513 // If this is a top-level #elif, inform the MIOpt. 1514 if (CurPPLexer->getConditionalStackDepth() == 0) 1515 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1516 1517 // If this is a #elif with a #else before it, report the error. 1518 if (CI.FoundElse) Diag(ElifToken, diag::pp_err_elif_after_else); 1519 1520 // Finally, skip the rest of the contents of this block and return the first 1521 // token after it. 1522 return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, 1523 /*FoundElse*/CI.FoundElse); 1524} 1525 1526