PPDirectives.cpp revision 137b6a6149c53dbbcb8fba98e524d9ad0f3c8736
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 } 403 404 // Do a standard file entry lookup. 405 CurDir = CurDirLookup; 406 const FileEntry *FE = 407 HeaderInfo.LookupFile(FilenameStart, FilenameEnd, 408 isAngled, FromDir, CurDir, CurFileEnt); 409 if (FE) return FE; 410 411 // Otherwise, see if this is a subframework header. If so, this is relative 412 // to one of the headers on the #include stack. Walk the list of the current 413 // headers on the #include stack and pass them to HeaderInfo. 414 if (IsFileLexer()) { 415 if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID()))) 416 if ((FE = HeaderInfo.LookupSubframeworkHeader(FilenameStart, FilenameEnd, 417 CurFileEnt))) 418 return FE; 419 } 420 421 for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) { 422 IncludeStackInfo &ISEntry = IncludeMacroStack[e-i-1]; 423 if (IsFileLexer(ISEntry)) { 424 if ((CurFileEnt = 425 SourceMgr.getFileEntryForID(ISEntry.ThePPLexer->getFileID()))) 426 if ((FE = HeaderInfo.LookupSubframeworkHeader(FilenameStart, 427 FilenameEnd, CurFileEnt))) 428 return FE; 429 } 430 } 431 432 // Otherwise, we really couldn't find the file. 433 return 0; 434} 435 436 437//===----------------------------------------------------------------------===// 438// Preprocessor Directive Handling. 439//===----------------------------------------------------------------------===// 440 441/// HandleDirective - This callback is invoked when the lexer sees a # token 442/// at the start of a line. This consumes the directive, modifies the 443/// lexer/preprocessor state, and advances the lexer(s) so that the next token 444/// read is the correct one. 445void Preprocessor::HandleDirective(Token &Result) { 446 // FIXME: Traditional: # with whitespace before it not recognized by K&R? 447 448 // We just parsed a # character at the start of a line, so we're in directive 449 // mode. Tell the lexer this so any newlines we see will be converted into an 450 // EOM token (which terminates the directive). 451 CurPPLexer->ParsingPreprocessorDirective = true; 452 453 ++NumDirectives; 454 455 // We are about to read a token. For the multiple-include optimization FA to 456 // work, we have to remember if we had read any tokens *before* this 457 // pp-directive. 458 bool ReadAnyTokensBeforeDirective = CurPPLexer->MIOpt.getHasReadAnyTokensVal(); 459 460 // Read the next token, the directive flavor. This isn't expanded due to 461 // C99 6.10.3p8. 462 LexUnexpandedToken(Result); 463 464 // C99 6.10.3p11: Is this preprocessor directive in macro invocation? e.g.: 465 // #define A(x) #x 466 // A(abc 467 // #warning blah 468 // def) 469 // If so, the user is relying on non-portable behavior, emit a diagnostic. 470 if (InMacroArgs) 471 Diag(Result, diag::ext_embedded_directive); 472 473TryAgain: 474 switch (Result.getKind()) { 475 case tok::eom: 476 return; // null directive. 477 case tok::comment: 478 // Handle stuff like "# /*foo*/ define X" in -E -C mode. 479 LexUnexpandedToken(Result); 480 goto TryAgain; 481 482 case tok::numeric_constant: // # 7 GNU line marker directive. 483 return HandleDigitDirective(Result); 484 default: 485 IdentifierInfo *II = Result.getIdentifierInfo(); 486 if (II == 0) break; // Not an identifier. 487 488 // Ask what the preprocessor keyword ID is. 489 switch (II->getPPKeywordID()) { 490 default: break; 491 // C99 6.10.1 - Conditional Inclusion. 492 case tok::pp_if: 493 return HandleIfDirective(Result, ReadAnyTokensBeforeDirective); 494 case tok::pp_ifdef: 495 return HandleIfdefDirective(Result, false, true/*not valid for miopt*/); 496 case tok::pp_ifndef: 497 return HandleIfdefDirective(Result, true, ReadAnyTokensBeforeDirective); 498 case tok::pp_elif: 499 return HandleElifDirective(Result); 500 case tok::pp_else: 501 return HandleElseDirective(Result); 502 case tok::pp_endif: 503 return HandleEndifDirective(Result); 504 505 // C99 6.10.2 - Source File Inclusion. 506 case tok::pp_include: 507 return HandleIncludeDirective(Result); // Handle #include. 508 509 // C99 6.10.3 - Macro Replacement. 510 case tok::pp_define: 511 return HandleDefineDirective(Result); 512 case tok::pp_undef: 513 return HandleUndefDirective(Result); 514 515 // C99 6.10.4 - Line Control. 516 case tok::pp_line: 517 return HandleLineDirective(Result); 518 519 // C99 6.10.5 - Error Directive. 520 case tok::pp_error: 521 return HandleUserDiagnosticDirective(Result, false); 522 523 // C99 6.10.6 - Pragma Directive. 524 case tok::pp_pragma: 525 return HandlePragmaDirective(); 526 527 // GNU Extensions. 528 case tok::pp_import: 529 return HandleImportDirective(Result); 530 case tok::pp_include_next: 531 return HandleIncludeNextDirective(Result); 532 533 case tok::pp_warning: 534 Diag(Result, diag::ext_pp_warning_directive); 535 return HandleUserDiagnosticDirective(Result, true); 536 case tok::pp_ident: 537 return HandleIdentSCCSDirective(Result); 538 case tok::pp_sccs: 539 return HandleIdentSCCSDirective(Result); 540 case tok::pp_assert: 541 //isExtension = true; // FIXME: implement #assert 542 break; 543 case tok::pp_unassert: 544 //isExtension = true; // FIXME: implement #unassert 545 break; 546 } 547 break; 548 } 549 550 // If we reached here, the preprocessing token is not valid! 551 Diag(Result, diag::err_pp_invalid_directive); 552 553 // Read the rest of the PP line. 554 DiscardUntilEndOfDirective(); 555 556 // Okay, we're done parsing the directive. 557} 558 559/// GetLineValue - Convert a numeric token into an unsigned value, emitting 560/// Diagnostic DiagID if it is invalid, and returning the value in Val. 561static bool GetLineValue(Token &DigitTok, unsigned &Val, 562 unsigned DiagID, Preprocessor &PP) { 563 if (DigitTok.isNot(tok::numeric_constant)) { 564 PP.Diag(DigitTok, DiagID); 565 566 if (DigitTok.isNot(tok::eom)) 567 PP.DiscardUntilEndOfDirective(); 568 return true; 569 } 570 571 llvm::SmallString<64> IntegerBuffer; 572 IntegerBuffer.resize(DigitTok.getLength()); 573 const char *DigitTokBegin = &IntegerBuffer[0]; 574 unsigned ActualLength = PP.getSpelling(DigitTok, DigitTokBegin); 575 NumericLiteralParser Literal(DigitTokBegin, DigitTokBegin+ActualLength, 576 DigitTok.getLocation(), PP); 577 if (Literal.hadError) 578 return true; // Error already emitted. 579 580 if (Literal.isFloatingLiteral() || Literal.isImaginary) { 581 PP.Diag(DigitTok, DiagID); 582 return true; 583 } 584 585 // Parse the integer literal into Result. 586 llvm::APInt APVal(32, 0); 587 if (Literal.GetIntegerValue(APVal)) { 588 // Overflow parsing integer literal. 589 PP.Diag(DigitTok, DiagID); 590 return true; 591 } 592 Val = APVal.getZExtValue(); 593 594 // Reject 0, this is needed both by #line numbers and flags. 595 if (Val == 0) { 596 PP.Diag(DigitTok, DiagID); 597 PP.DiscardUntilEndOfDirective(); 598 return true; 599 } 600 601 return false; 602} 603 604/// HandleLineDirective - Handle #line directive: C99 6.10.4. The two 605/// acceptable forms are: 606/// # line digit-sequence 607/// # line digit-sequence "s-char-sequence" 608void Preprocessor::HandleLineDirective(Token &Tok) { 609 // Read the line # and string argument. Per C99 6.10.4p5, these tokens are 610 // expanded. 611 Token DigitTok; 612 Lex(DigitTok); 613 614 // Validate the number and convert it to an unsigned. 615 unsigned LineNo; 616 if (GetLineValue(DigitTok, LineNo, diag::err_pp_line_requires_integer, *this)) 617 return; 618 619 // Enforce C99 6.10.4p3: "The digit sequence shall not specify ... a 620 // number greater than 2147483647". C90 requires that the line # be <= 32767. 621 unsigned LineLimit = Features.C99 ? 2147483648U : 32768U; 622 if (LineNo >= LineLimit) 623 Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit; 624 625 int FilenameID = -1; 626 Token StrTok; 627 Lex(StrTok); 628 629 // If the StrTok is "eom", then it wasn't present. Otherwise, it must be a 630 // string followed by eom. 631 if (StrTok.is(tok::eom)) 632 ; // ok 633 else if (StrTok.isNot(tok::string_literal)) { 634 Diag(StrTok, diag::err_pp_line_invalid_filename); 635 DiscardUntilEndOfDirective(); 636 return; 637 } else { 638 // Parse and validate the string, converting it into a unique ID. 639 StringLiteralParser Literal(&StrTok, 1, *this); 640 assert(!Literal.AnyWide && "Didn't allow wide strings in"); 641 if (Literal.hadError) 642 return DiscardUntilEndOfDirective(); 643 if (Literal.Pascal) { 644 Diag(StrTok, diag::err_pp_linemarker_invalid_filename); 645 return DiscardUntilEndOfDirective(); 646 } 647 FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString(), 648 Literal.GetStringLength()); 649 650 // Verify that there is nothing after the string, other than EOM. 651 CheckEndOfDirective("#line"); 652 } 653 654 SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID); 655} 656 657/// ReadLineMarkerFlags - Parse and validate any flags at the end of a GNU line 658/// marker directive. 659static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit, 660 bool &IsSystemHeader, bool &IsExternCHeader, 661 Preprocessor &PP) { 662 unsigned FlagVal; 663 Token FlagTok; 664 PP.Lex(FlagTok); 665 if (FlagTok.is(tok::eom)) return false; 666 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP)) 667 return true; 668 669 if (FlagVal == 1) { 670 IsFileEntry = true; 671 672 PP.Lex(FlagTok); 673 if (FlagTok.is(tok::eom)) return false; 674 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP)) 675 return true; 676 } else if (FlagVal == 2) { 677 IsFileExit = true; 678 679 SourceManager &SM = PP.getSourceManager(); 680 // If we are leaving the current presumed file, check to make sure the 681 // presumed include stack isn't empty! 682 FileID CurFileID = 683 SM.getDecomposedInstantiationLoc(FlagTok.getLocation()).first; 684 PresumedLoc PLoc = SM.getPresumedLoc(FlagTok.getLocation()); 685 686 // If there is no include loc (main file) or if the include loc is in a 687 // different physical file, then we aren't in a "1" line marker flag region. 688 SourceLocation IncLoc = PLoc.getIncludeLoc(); 689 if (IncLoc.isInvalid() || 690 SM.getDecomposedInstantiationLoc(IncLoc).first != CurFileID) { 691 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_pop); 692 PP.DiscardUntilEndOfDirective(); 693 return true; 694 } 695 696 PP.Lex(FlagTok); 697 if (FlagTok.is(tok::eom)) return false; 698 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP)) 699 return true; 700 } 701 702 // We must have 3 if there are still flags. 703 if (FlagVal != 3) { 704 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); 705 PP.DiscardUntilEndOfDirective(); 706 return true; 707 } 708 709 IsSystemHeader = true; 710 711 PP.Lex(FlagTok); 712 if (FlagTok.is(tok::eom)) return false; 713 if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP)) 714 return true; 715 716 // We must have 4 if there is yet another flag. 717 if (FlagVal != 4) { 718 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); 719 PP.DiscardUntilEndOfDirective(); 720 return true; 721 } 722 723 IsExternCHeader = true; 724 725 PP.Lex(FlagTok); 726 if (FlagTok.is(tok::eom)) return false; 727 728 // There are no more valid flags here. 729 PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); 730 PP.DiscardUntilEndOfDirective(); 731 return true; 732} 733 734/// HandleDigitDirective - Handle a GNU line marker directive, whose syntax is 735/// one of the following forms: 736/// 737/// # 42 738/// # 42 "file" ('1' | '2')? 739/// # 42 "file" ('1' | '2')? '3' '4'? 740/// 741void Preprocessor::HandleDigitDirective(Token &DigitTok) { 742 // Validate the number and convert it to an unsigned. GNU does not have a 743 // line # limit other than it fit in 32-bits. 744 unsigned LineNo; 745 if (GetLineValue(DigitTok, LineNo, diag::err_pp_linemarker_requires_integer, 746 *this)) 747 return; 748 749 Token StrTok; 750 Lex(StrTok); 751 752 bool IsFileEntry = false, IsFileExit = false; 753 bool IsSystemHeader = false, IsExternCHeader = false; 754 int FilenameID = -1; 755 756 // If the StrTok is "eom", then it wasn't present. Otherwise, it must be a 757 // string followed by eom. 758 if (StrTok.is(tok::eom)) 759 ; // ok 760 else if (StrTok.isNot(tok::string_literal)) { 761 Diag(StrTok, diag::err_pp_linemarker_invalid_filename); 762 return DiscardUntilEndOfDirective(); 763 } else { 764 // Parse and validate the string, converting it into a unique ID. 765 StringLiteralParser Literal(&StrTok, 1, *this); 766 assert(!Literal.AnyWide && "Didn't allow wide strings in"); 767 if (Literal.hadError) 768 return DiscardUntilEndOfDirective(); 769 if (Literal.Pascal) { 770 Diag(StrTok, diag::err_pp_linemarker_invalid_filename); 771 return DiscardUntilEndOfDirective(); 772 } 773 FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString(), 774 Literal.GetStringLength()); 775 776 // If a filename was present, read any flags that are present. 777 if (ReadLineMarkerFlags(IsFileEntry, IsFileExit, 778 IsSystemHeader, IsExternCHeader, *this)) 779 return; 780 } 781 782 // Create a line note with this information. 783 SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID, 784 IsFileEntry, IsFileExit, 785 IsSystemHeader, IsExternCHeader); 786} 787 788 789/// HandleUserDiagnosticDirective - Handle a #warning or #error directive. 790/// 791void Preprocessor::HandleUserDiagnosticDirective(Token &Tok, 792 bool isWarning) { 793 // PTH doesn't emit #warning or #error directives. 794 if (CurPTHLexer) 795 return CurPTHLexer->DiscardToEndOfLine(); 796 797 // Read the rest of the line raw. We do this because we don't want macros 798 // to be expanded and we don't require that the tokens be valid preprocessing 799 // tokens. For example, this is allowed: "#warning ` 'foo". GCC does 800 // collapse multiple consequtive white space between tokens, but this isn't 801 // specified by the standard. 802 std::string Message = CurLexer->ReadToEndOfLine(); 803 if (isWarning) 804 Diag(Tok, diag::pp_hash_warning) << Message; 805 else 806 Diag(Tok, diag::err_pp_hash_error) << Message; 807} 808 809/// HandleIdentSCCSDirective - Handle a #ident/#sccs directive. 810/// 811void Preprocessor::HandleIdentSCCSDirective(Token &Tok) { 812 // Yes, this directive is an extension. 813 Diag(Tok, diag::ext_pp_ident_directive); 814 815 // Read the string argument. 816 Token StrTok; 817 Lex(StrTok); 818 819 // If the token kind isn't a string, it's a malformed directive. 820 if (StrTok.isNot(tok::string_literal) && 821 StrTok.isNot(tok::wide_string_literal)) { 822 Diag(StrTok, diag::err_pp_malformed_ident); 823 if (StrTok.isNot(tok::eom)) 824 DiscardUntilEndOfDirective(); 825 return; 826 } 827 828 // Verify that there is nothing after the string, other than EOM. 829 CheckEndOfDirective("#ident"); 830 831 if (Callbacks) 832 Callbacks->Ident(Tok.getLocation(), getSpelling(StrTok)); 833} 834 835//===----------------------------------------------------------------------===// 836// Preprocessor Include Directive Handling. 837//===----------------------------------------------------------------------===// 838 839/// GetIncludeFilenameSpelling - Turn the specified lexer token into a fully 840/// checked and spelled filename, e.g. as an operand of #include. This returns 841/// true if the input filename was in <>'s or false if it were in ""'s. The 842/// caller is expected to provide a buffer that is large enough to hold the 843/// spelling of the filename, but is also expected to handle the case when 844/// this method decides to use a different buffer. 845bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc, 846 const char *&BufStart, 847 const char *&BufEnd) { 848 // Get the text form of the filename. 849 assert(BufStart != BufEnd && "Can't have tokens with empty spellings!"); 850 851 // Make sure the filename is <x> or "x". 852 bool isAngled; 853 if (BufStart[0] == '<') { 854 if (BufEnd[-1] != '>') { 855 Diag(Loc, diag::err_pp_expects_filename); 856 BufStart = 0; 857 return true; 858 } 859 isAngled = true; 860 } else if (BufStart[0] == '"') { 861 if (BufEnd[-1] != '"') { 862 Diag(Loc, diag::err_pp_expects_filename); 863 BufStart = 0; 864 return true; 865 } 866 isAngled = false; 867 } else { 868 Diag(Loc, diag::err_pp_expects_filename); 869 BufStart = 0; 870 return true; 871 } 872 873 // Diagnose #include "" as invalid. 874 if (BufEnd-BufStart <= 2) { 875 Diag(Loc, diag::err_pp_empty_filename); 876 BufStart = 0; 877 return ""; 878 } 879 880 // Skip the brackets. 881 ++BufStart; 882 --BufEnd; 883 return isAngled; 884} 885 886/// ConcatenateIncludeName - Handle cases where the #include name is expanded 887/// from a macro as multiple tokens, which need to be glued together. This 888/// occurs for code like: 889/// #define FOO <a/b.h> 890/// #include FOO 891/// because in this case, "<a/b.h>" is returned as 7 tokens, not one. 892/// 893/// This code concatenates and consumes tokens up to the '>' token. It returns 894/// false if the > was found, otherwise it returns true if it finds and consumes 895/// the EOM marker. 896static bool ConcatenateIncludeName(llvm::SmallVector<char, 128> &FilenameBuffer, 897 Preprocessor &PP) { 898 Token CurTok; 899 900 PP.Lex(CurTok); 901 while (CurTok.isNot(tok::eom)) { 902 // Append the spelling of this token to the buffer. If there was a space 903 // before it, add it now. 904 if (CurTok.hasLeadingSpace()) 905 FilenameBuffer.push_back(' '); 906 907 // Get the spelling of the token, directly into FilenameBuffer if possible. 908 unsigned PreAppendSize = FilenameBuffer.size(); 909 FilenameBuffer.resize(PreAppendSize+CurTok.getLength()); 910 911 const char *BufPtr = &FilenameBuffer[PreAppendSize]; 912 unsigned ActualLen = PP.getSpelling(CurTok, BufPtr); 913 914 // If the token was spelled somewhere else, copy it into FilenameBuffer. 915 if (BufPtr != &FilenameBuffer[PreAppendSize]) 916 memcpy(&FilenameBuffer[PreAppendSize], BufPtr, ActualLen); 917 918 // Resize FilenameBuffer to the correct size. 919 if (CurTok.getLength() != ActualLen) 920 FilenameBuffer.resize(PreAppendSize+ActualLen); 921 922 // If we found the '>' marker, return success. 923 if (CurTok.is(tok::greater)) 924 return false; 925 926 PP.Lex(CurTok); 927 } 928 929 // If we hit the eom marker, emit an error and return true so that the caller 930 // knows the EOM has been read. 931 PP.Diag(CurTok.getLocation(), diag::err_pp_expects_filename); 932 return true; 933} 934 935/// HandleIncludeDirective - The "#include" tokens have just been read, read the 936/// file to be included from the lexer, then include it! This is a common 937/// routine with functionality shared between #include, #include_next and 938/// #import. LookupFrom is set when this is a #include_next directive, it 939/// specifies the file to start searching from. 940void Preprocessor::HandleIncludeDirective(Token &IncludeTok, 941 const DirectoryLookup *LookupFrom, 942 bool isImport) { 943 944 Token FilenameTok; 945 CurPPLexer->LexIncludeFilename(FilenameTok); 946 947 // Reserve a buffer to get the spelling. 948 llvm::SmallVector<char, 128> FilenameBuffer; 949 const char *FilenameStart, *FilenameEnd; 950 951 switch (FilenameTok.getKind()) { 952 case tok::eom: 953 // If the token kind is EOM, the error has already been diagnosed. 954 return; 955 956 case tok::angle_string_literal: 957 case tok::string_literal: { 958 FilenameBuffer.resize(FilenameTok.getLength()); 959 FilenameStart = &FilenameBuffer[0]; 960 unsigned Len = getSpelling(FilenameTok, FilenameStart); 961 FilenameEnd = FilenameStart+Len; 962 break; 963 } 964 965 case tok::less: 966 // This could be a <foo/bar.h> file coming from a macro expansion. In this 967 // case, glue the tokens together into FilenameBuffer and interpret those. 968 FilenameBuffer.push_back('<'); 969 if (ConcatenateIncludeName(FilenameBuffer, *this)) 970 return; // Found <eom> but no ">"? Diagnostic already emitted. 971 FilenameStart = &FilenameBuffer[0]; 972 FilenameEnd = &FilenameBuffer[FilenameBuffer.size()]; 973 break; 974 default: 975 Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename); 976 DiscardUntilEndOfDirective(); 977 return; 978 } 979 980 bool isAngled = GetIncludeFilenameSpelling(FilenameTok.getLocation(), 981 FilenameStart, FilenameEnd); 982 // If GetIncludeFilenameSpelling set the start ptr to null, there was an 983 // error. 984 if (FilenameStart == 0) { 985 DiscardUntilEndOfDirective(); 986 return; 987 } 988 989 // Verify that there is nothing after the filename, other than EOM. Use the 990 // preprocessor to lex this in case lexing the filename entered a macro. 991 CheckEndOfDirective("#include"); 992 993 // Check that we don't have infinite #include recursion. 994 if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1) { 995 Diag(FilenameTok, diag::err_pp_include_too_deep); 996 return; 997 } 998 999 // Search include directories. 1000 const DirectoryLookup *CurDir; 1001 const FileEntry *File = LookupFile(FilenameStart, FilenameEnd, 1002 isAngled, LookupFrom, CurDir); 1003 if (File == 0) { 1004 Diag(FilenameTok, diag::err_pp_file_not_found) 1005 << std::string(FilenameStart, FilenameEnd); 1006 return; 1007 } 1008 1009 // Ask HeaderInfo if we should enter this #include file. If not, #including 1010 // this file will have no effect. 1011 if (!HeaderInfo.ShouldEnterIncludeFile(File, isImport)) 1012 return; 1013 1014 // The #included file will be considered to be a system header if either it is 1015 // in a system include directory, or if the #includer is a system include 1016 // header. 1017 SrcMgr::CharacteristicKind FileCharacter = 1018 std::max(HeaderInfo.getFileDirFlavor(File), 1019 SourceMgr.getFileCharacteristic(FilenameTok.getLocation())); 1020 1021 // Look up the file, create a File ID for it. 1022 FileID FID = SourceMgr.createFileID(File, FilenameTok.getLocation(), 1023 FileCharacter); 1024 if (FID.isInvalid()) { 1025 Diag(FilenameTok, diag::err_pp_file_not_found) 1026 << std::string(FilenameStart, FilenameEnd); 1027 return; 1028 } 1029 1030 // Finally, if all is good, enter the new file! 1031 EnterSourceFile(FID, CurDir); 1032} 1033 1034/// HandleIncludeNextDirective - Implements #include_next. 1035/// 1036void Preprocessor::HandleIncludeNextDirective(Token &IncludeNextTok) { 1037 Diag(IncludeNextTok, diag::ext_pp_include_next_directive); 1038 1039 // #include_next is like #include, except that we start searching after 1040 // the current found directory. If we can't do this, issue a 1041 // diagnostic. 1042 const DirectoryLookup *Lookup = CurDirLookup; 1043 if (isInPrimaryFile()) { 1044 Lookup = 0; 1045 Diag(IncludeNextTok, diag::pp_include_next_in_primary); 1046 } else if (Lookup == 0) { 1047 Diag(IncludeNextTok, diag::pp_include_next_absolute_path); 1048 } else { 1049 // Start looking up in the next directory. 1050 ++Lookup; 1051 } 1052 1053 return HandleIncludeDirective(IncludeNextTok, Lookup); 1054} 1055 1056/// HandleImportDirective - Implements #import. 1057/// 1058void Preprocessor::HandleImportDirective(Token &ImportTok) { 1059 Diag(ImportTok, diag::ext_pp_import_directive); 1060 1061 return HandleIncludeDirective(ImportTok, 0, true); 1062} 1063 1064//===----------------------------------------------------------------------===// 1065// Preprocessor Macro Directive Handling. 1066//===----------------------------------------------------------------------===// 1067 1068/// ReadMacroDefinitionArgList - The ( starting an argument list of a macro 1069/// definition has just been read. Lex the rest of the arguments and the 1070/// closing ), updating MI with what we learn. Return true if an error occurs 1071/// parsing the arg list. 1072bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) { 1073 llvm::SmallVector<IdentifierInfo*, 32> Arguments; 1074 1075 Token Tok; 1076 while (1) { 1077 LexUnexpandedToken(Tok); 1078 switch (Tok.getKind()) { 1079 case tok::r_paren: 1080 // Found the end of the argument list. 1081 if (Arguments.empty()) { // #define FOO() 1082 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1083 return false; 1084 } 1085 // Otherwise we have #define FOO(A,) 1086 Diag(Tok, diag::err_pp_expected_ident_in_arg_list); 1087 return true; 1088 case tok::ellipsis: // #define X(... -> C99 varargs 1089 // Warn if use of C99 feature in non-C99 mode. 1090 if (!Features.C99) Diag(Tok, diag::ext_variadic_macro); 1091 1092 // Lex the token after the identifier. 1093 LexUnexpandedToken(Tok); 1094 if (Tok.isNot(tok::r_paren)) { 1095 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); 1096 return true; 1097 } 1098 // Add the __VA_ARGS__ identifier as an argument. 1099 Arguments.push_back(Ident__VA_ARGS__); 1100 MI->setIsC99Varargs(); 1101 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1102 return false; 1103 case tok::eom: // #define X( 1104 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); 1105 return true; 1106 default: 1107 // Handle keywords and identifiers here to accept things like 1108 // #define Foo(for) for. 1109 IdentifierInfo *II = Tok.getIdentifierInfo(); 1110 if (II == 0) { 1111 // #define X(1 1112 Diag(Tok, diag::err_pp_invalid_tok_in_arg_list); 1113 return true; 1114 } 1115 1116 // If this is already used as an argument, it is used multiple times (e.g. 1117 // #define X(A,A. 1118 if (std::find(Arguments.begin(), Arguments.end(), II) != 1119 Arguments.end()) { // C99 6.10.3p6 1120 Diag(Tok, diag::err_pp_duplicate_name_in_arg_list) << II; 1121 return true; 1122 } 1123 1124 // Add the argument to the macro info. 1125 Arguments.push_back(II); 1126 1127 // Lex the token after the identifier. 1128 LexUnexpandedToken(Tok); 1129 1130 switch (Tok.getKind()) { 1131 default: // #define X(A B 1132 Diag(Tok, diag::err_pp_expected_comma_in_arg_list); 1133 return true; 1134 case tok::r_paren: // #define X(A) 1135 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1136 return false; 1137 case tok::comma: // #define X(A, 1138 break; 1139 case tok::ellipsis: // #define X(A... -> GCC extension 1140 // Diagnose extension. 1141 Diag(Tok, diag::ext_named_variadic_macro); 1142 1143 // Lex the token after the identifier. 1144 LexUnexpandedToken(Tok); 1145 if (Tok.isNot(tok::r_paren)) { 1146 Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); 1147 return true; 1148 } 1149 1150 MI->setIsGNUVarargs(); 1151 MI->setArgumentList(Arguments.begin(), Arguments.end()); 1152 return false; 1153 } 1154 } 1155 } 1156} 1157 1158/// HandleDefineDirective - Implements #define. This consumes the entire macro 1159/// line then lets the caller lex the next real token. 1160void Preprocessor::HandleDefineDirective(Token &DefineTok) { 1161 ++NumDefined; 1162 1163 Token MacroNameTok; 1164 ReadMacroName(MacroNameTok, 1); 1165 1166 // Error reading macro name? If so, diagnostic already issued. 1167 if (MacroNameTok.is(tok::eom)) 1168 return; 1169 1170 // If we are supposed to keep comments in #defines, reenable comment saving 1171 // mode. 1172 if (CurLexer) CurLexer->SetCommentRetentionState(KeepMacroComments); 1173 1174 // Create the new macro. 1175 MacroInfo *MI = AllocateMacroInfo(MacroNameTok.getLocation()); 1176 1177 Token Tok; 1178 LexUnexpandedToken(Tok); 1179 1180 // If this is a function-like macro definition, parse the argument list, 1181 // marking each of the identifiers as being used as macro arguments. Also, 1182 // check other constraints on the first token of the macro body. 1183 if (Tok.is(tok::eom)) { 1184 // If there is no body to this macro, we have no special handling here. 1185 } else if (Tok.is(tok::l_paren) && !Tok.hasLeadingSpace()) { 1186 // This is a function-like macro definition. Read the argument list. 1187 MI->setIsFunctionLike(); 1188 if (ReadMacroDefinitionArgList(MI)) { 1189 // Forget about MI. 1190 ReleaseMacroInfo(MI); 1191 // Throw away the rest of the line. 1192 if (CurPPLexer->ParsingPreprocessorDirective) 1193 DiscardUntilEndOfDirective(); 1194 return; 1195 } 1196 1197 // Read the first token after the arg list for down below. 1198 LexUnexpandedToken(Tok); 1199 } else if (!Tok.hasLeadingSpace()) { 1200 // C99 requires whitespace between the macro definition and the body. Emit 1201 // a diagnostic for something like "#define X+". 1202 if (Features.C99) { 1203 Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name); 1204 } else { 1205 // FIXME: C90/C++ do not get this diagnostic, but it does get a similar 1206 // one in some cases! 1207 } 1208 } else { 1209 // This is a normal token with leading space. Clear the leading space 1210 // marker on the first token to get proper expansion. 1211 Tok.clearFlag(Token::LeadingSpace); 1212 } 1213 1214 // If this is a definition of a variadic C99 function-like macro, not using 1215 // the GNU named varargs extension, enabled __VA_ARGS__. 1216 1217 // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro. 1218 // This gets unpoisoned where it is allowed. 1219 assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned!"); 1220 if (MI->isC99Varargs()) 1221 Ident__VA_ARGS__->setIsPoisoned(false); 1222 1223 // Read the rest of the macro body. 1224 if (MI->isObjectLike()) { 1225 // Object-like macros are very simple, just read their body. 1226 while (Tok.isNot(tok::eom)) { 1227 MI->AddTokenToBody(Tok); 1228 // Get the next token of the macro. 1229 LexUnexpandedToken(Tok); 1230 } 1231 1232 } else { 1233 // Otherwise, read the body of a function-like macro. This has to validate 1234 // the # (stringize) operator. 1235 while (Tok.isNot(tok::eom)) { 1236 MI->AddTokenToBody(Tok); 1237 1238 // Check C99 6.10.3.2p1: ensure that # operators are followed by macro 1239 // parameters in function-like macro expansions. 1240 if (Tok.isNot(tok::hash)) { 1241 // Get the next token of the macro. 1242 LexUnexpandedToken(Tok); 1243 continue; 1244 } 1245 1246 // Get the next token of the macro. 1247 LexUnexpandedToken(Tok); 1248 1249 // Not a macro arg identifier? 1250 if (!Tok.getIdentifierInfo() || 1251 MI->getArgumentNum(Tok.getIdentifierInfo()) == -1) { 1252 Diag(Tok, diag::err_pp_stringize_not_parameter); 1253 ReleaseMacroInfo(MI); 1254 1255 // Disable __VA_ARGS__ again. 1256 Ident__VA_ARGS__->setIsPoisoned(true); 1257 return; 1258 } 1259 1260 // Things look ok, add the param name token to the macro. 1261 MI->AddTokenToBody(Tok); 1262 1263 // Get the next token of the macro. 1264 LexUnexpandedToken(Tok); 1265 } 1266 } 1267 1268 1269 // Disable __VA_ARGS__ again. 1270 Ident__VA_ARGS__->setIsPoisoned(true); 1271 1272 // Check that there is no paste (##) operator at the begining or end of the 1273 // replacement list. 1274 unsigned NumTokens = MI->getNumTokens(); 1275 if (NumTokens != 0) { 1276 if (MI->getReplacementToken(0).is(tok::hashhash)) { 1277 Diag(MI->getReplacementToken(0), diag::err_paste_at_start); 1278 ReleaseMacroInfo(MI); 1279 return; 1280 } 1281 if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) { 1282 Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end); 1283 ReleaseMacroInfo(MI); 1284 return; 1285 } 1286 } 1287 1288 // If this is the primary source file, remember that this macro hasn't been 1289 // used yet. 1290 if (isInPrimaryFile()) 1291 MI->setIsUsed(false); 1292 1293 // Finally, if this identifier already had a macro defined for it, verify that 1294 // the macro bodies are identical and free the old definition. 1295 if (MacroInfo *OtherMI = getMacroInfo(MacroNameTok.getIdentifierInfo())) { 1296 // It is very common for system headers to have tons of macro redefinitions 1297 // and for warnings to be disabled in system headers. If this is the case, 1298 // then don't bother calling MacroInfo::isIdenticalTo. 1299 if (!Diags.getSuppressSystemWarnings() || 1300 !SourceMgr.isInSystemHeader(DefineTok.getLocation())) { 1301 if (!OtherMI->isUsed()) 1302 Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used); 1303 1304 // Macros must be identical. This means all tokes and whitespace 1305 // separation must be the same. C99 6.10.3.2. 1306 if (!MI->isIdenticalTo(*OtherMI, *this)) { 1307 Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef) 1308 << MacroNameTok.getIdentifierInfo(); 1309 Diag(OtherMI->getDefinitionLoc(), diag::note_previous_definition); 1310 } 1311 } 1312 1313 ReleaseMacroInfo(OtherMI); 1314 } 1315 1316 setMacroInfo(MacroNameTok.getIdentifierInfo(), MI); 1317} 1318 1319/// HandleUndefDirective - Implements #undef. 1320/// 1321void Preprocessor::HandleUndefDirective(Token &UndefTok) { 1322 ++NumUndefined; 1323 1324 Token MacroNameTok; 1325 ReadMacroName(MacroNameTok, 2); 1326 1327 // Error reading macro name? If so, diagnostic already issued. 1328 if (MacroNameTok.is(tok::eom)) 1329 return; 1330 1331 // Check to see if this is the last token on the #undef line. 1332 CheckEndOfDirective("#undef"); 1333 1334 // Okay, we finally have a valid identifier to undef. 1335 MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo()); 1336 1337 // If the macro is not defined, this is a noop undef, just return. 1338 if (MI == 0) return; 1339 1340 if (!MI->isUsed()) 1341 Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used); 1342 1343 // Free macro definition. 1344 ReleaseMacroInfo(MI); 1345 setMacroInfo(MacroNameTok.getIdentifierInfo(), 0); 1346} 1347 1348 1349//===----------------------------------------------------------------------===// 1350// Preprocessor Conditional Directive Handling. 1351//===----------------------------------------------------------------------===// 1352 1353/// HandleIfdefDirective - Implements the #ifdef/#ifndef directive. isIfndef is 1354/// true when this is a #ifndef directive. ReadAnyTokensBeforeDirective is true 1355/// if any tokens have been returned or pp-directives activated before this 1356/// #ifndef has been lexed. 1357/// 1358void Preprocessor::HandleIfdefDirective(Token &Result, bool isIfndef, 1359 bool ReadAnyTokensBeforeDirective) { 1360 ++NumIf; 1361 Token DirectiveTok = Result; 1362 1363 Token MacroNameTok; 1364 ReadMacroName(MacroNameTok); 1365 1366 // Error reading macro name? If so, diagnostic already issued. 1367 if (MacroNameTok.is(tok::eom)) { 1368 // Skip code until we get to #endif. This helps with recovery by not 1369 // emitting an error when the #endif is reached. 1370 SkipExcludedConditionalBlock(DirectiveTok.getLocation(), 1371 /*Foundnonskip*/false, /*FoundElse*/false); 1372 return; 1373 } 1374 1375 // Check to see if this is the last token on the #if[n]def line. 1376 CheckEndOfDirective(isIfndef ? "#ifndef" : "#ifdef"); 1377 1378 if (CurPPLexer->getConditionalStackDepth() == 0) { 1379 // If the start of a top-level #ifdef, inform MIOpt. 1380 if (!ReadAnyTokensBeforeDirective) { 1381 assert(isIfndef && "#ifdef shouldn't reach here"); 1382 CurPPLexer->MIOpt.EnterTopLevelIFNDEF(MacroNameTok.getIdentifierInfo()); 1383 } else 1384 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1385 } 1386 1387 IdentifierInfo *MII = MacroNameTok.getIdentifierInfo(); 1388 MacroInfo *MI = getMacroInfo(MII); 1389 1390 // If there is a macro, process it. 1391 if (MI) // Mark it used. 1392 MI->setIsUsed(true); 1393 1394 // Should we include the stuff contained by this directive? 1395 if (!MI == isIfndef) { 1396 // Yes, remember that we are inside a conditional, then lex the next token. 1397 CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(), /*wasskip*/false, 1398 /*foundnonskip*/true, /*foundelse*/false); 1399 } else { 1400 // No, skip the contents of this block and return the first token after it. 1401 SkipExcludedConditionalBlock(DirectiveTok.getLocation(), 1402 /*Foundnonskip*/false, 1403 /*FoundElse*/false); 1404 } 1405} 1406 1407/// HandleIfDirective - Implements the #if directive. 1408/// 1409void Preprocessor::HandleIfDirective(Token &IfToken, 1410 bool ReadAnyTokensBeforeDirective) { 1411 ++NumIf; 1412 1413 // Parse and evaluation the conditional expression. 1414 IdentifierInfo *IfNDefMacro = 0; 1415 bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro); 1416 1417 1418 // If this condition is equivalent to #ifndef X, and if this is the first 1419 // directive seen, handle it for the multiple-include optimization. 1420 if (CurPPLexer->getConditionalStackDepth() == 0) { 1421 if (!ReadAnyTokensBeforeDirective && IfNDefMacro) 1422 CurPPLexer->MIOpt.EnterTopLevelIFNDEF(IfNDefMacro); 1423 else 1424 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1425 } 1426 1427 // Should we include the stuff contained by this directive? 1428 if (ConditionalTrue) { 1429 // Yes, remember that we are inside a conditional, then lex the next token. 1430 CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false, 1431 /*foundnonskip*/true, /*foundelse*/false); 1432 } else { 1433 // No, skip the contents of this block and return the first token after it. 1434 SkipExcludedConditionalBlock(IfToken.getLocation(), /*Foundnonskip*/false, 1435 /*FoundElse*/false); 1436 } 1437} 1438 1439/// HandleEndifDirective - Implements the #endif directive. 1440/// 1441void Preprocessor::HandleEndifDirective(Token &EndifToken) { 1442 ++NumEndif; 1443 1444 // Check that this is the whole directive. 1445 CheckEndOfDirective("#endif"); 1446 1447 PPConditionalInfo CondInfo; 1448 if (CurPPLexer->popConditionalLevel(CondInfo)) { 1449 // No conditionals on the stack: this is an #endif without an #if. 1450 Diag(EndifToken, diag::err_pp_endif_without_if); 1451 return; 1452 } 1453 1454 // If this the end of a top-level #endif, inform MIOpt. 1455 if (CurPPLexer->getConditionalStackDepth() == 0) 1456 CurPPLexer->MIOpt.ExitTopLevelConditional(); 1457 1458 assert(!CondInfo.WasSkipping && !CurPPLexer->LexingRawMode && 1459 "This code should only be reachable in the non-skipping case!"); 1460} 1461 1462 1463void Preprocessor::HandleElseDirective(Token &Result) { 1464 ++NumElse; 1465 1466 // #else directive in a non-skipping conditional... start skipping. 1467 CheckEndOfDirective("#else"); 1468 1469 PPConditionalInfo CI; 1470 if (CurPPLexer->popConditionalLevel(CI)) { 1471 Diag(Result, diag::pp_err_else_without_if); 1472 return; 1473 } 1474 1475 // If this is a top-level #else, inform the MIOpt. 1476 if (CurPPLexer->getConditionalStackDepth() == 0) 1477 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1478 1479 // If this is a #else with a #else before it, report the error. 1480 if (CI.FoundElse) Diag(Result, diag::pp_err_else_after_else); 1481 1482 // Finally, skip the rest of the contents of this block and return the first 1483 // token after it. 1484 return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, 1485 /*FoundElse*/true); 1486} 1487 1488void Preprocessor::HandleElifDirective(Token &ElifToken) { 1489 ++NumElse; 1490 1491 // #elif directive in a non-skipping conditional... start skipping. 1492 // We don't care what the condition is, because we will always skip it (since 1493 // the block immediately before it was included). 1494 DiscardUntilEndOfDirective(); 1495 1496 PPConditionalInfo CI; 1497 if (CurPPLexer->popConditionalLevel(CI)) { 1498 Diag(ElifToken, diag::pp_err_elif_without_if); 1499 return; 1500 } 1501 1502 // If this is a top-level #elif, inform the MIOpt. 1503 if (CurPPLexer->getConditionalStackDepth() == 0) 1504 CurPPLexer->MIOpt.EnterTopLevelConditional(); 1505 1506 // If this is a #elif with a #else before it, report the error. 1507 if (CI.FoundElse) Diag(ElifToken, diag::pp_err_elif_after_else); 1508 1509 // Finally, skip the rest of the contents of this block and return the first 1510 // token after it. 1511 return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, 1512 /*FoundElse*/CI.FoundElse); 1513} 1514 1515