Pragma.cpp revision f45b646244705410866d62f1d8bf017a047ed662
1//===--- Pragma.cpp - Pragma registration and handling --------------------===// 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 the PragmaHandler/PragmaTable interfaces and implements 11// pragma related methods of the Preprocessor class. 12// 13//===----------------------------------------------------------------------===// 14 15#include "clang/Lex/Pragma.h" 16#include "clang/Lex/HeaderSearch.h" 17#include "clang/Lex/LiteralSupport.h" 18#include "clang/Lex/Preprocessor.h" 19#include "clang/Lex/LexDiagnostic.h" 20#include "clang/Basic/FileManager.h" 21#include "clang/Basic/SourceManager.h" 22#include <algorithm> 23using namespace clang; 24 25// Out-of-line destructor to provide a home for the class. 26PragmaHandler::~PragmaHandler() { 27} 28 29//===----------------------------------------------------------------------===// 30// PragmaNamespace Implementation. 31//===----------------------------------------------------------------------===// 32 33 34PragmaNamespace::~PragmaNamespace() { 35 for (unsigned i = 0, e = Handlers.size(); i != e; ++i) 36 delete Handlers[i]; 37} 38 39/// FindHandler - Check to see if there is already a handler for the 40/// specified name. If not, return the handler for the null identifier if it 41/// exists, otherwise return null. If IgnoreNull is true (the default) then 42/// the null handler isn't returned on failure to match. 43PragmaHandler *PragmaNamespace::FindHandler(const IdentifierInfo *Name, 44 bool IgnoreNull) const { 45 PragmaHandler *NullHandler = 0; 46 for (unsigned i = 0, e = Handlers.size(); i != e; ++i) { 47 if (Handlers[i]->getName() == Name) 48 return Handlers[i]; 49 50 if (Handlers[i]->getName() == 0) 51 NullHandler = Handlers[i]; 52 } 53 return IgnoreNull ? 0 : NullHandler; 54} 55 56void PragmaNamespace::RemovePragmaHandler(PragmaHandler *Handler) { 57 for (unsigned i = 0, e = Handlers.size(); i != e; ++i) { 58 if (Handlers[i] == Handler) { 59 Handlers[i] = Handlers.back(); 60 Handlers.pop_back(); 61 return; 62 } 63 } 64 assert(0 && "Handler not registered in this namespace"); 65} 66 67void PragmaNamespace::HandlePragma(Preprocessor &PP, Token &Tok) { 68 // Read the 'namespace' that the directive is in, e.g. STDC. Do not macro 69 // expand it, the user can have a STDC #define, that should not affect this. 70 PP.LexUnexpandedToken(Tok); 71 72 // Get the handler for this token. If there is no handler, ignore the pragma. 73 PragmaHandler *Handler = FindHandler(Tok.getIdentifierInfo(), false); 74 if (Handler == 0) { 75 PP.Diag(Tok, diag::warn_pragma_ignored); 76 return; 77 } 78 79 // Otherwise, pass it down. 80 Handler->HandlePragma(PP, Tok); 81} 82 83//===----------------------------------------------------------------------===// 84// Preprocessor Pragma Directive Handling. 85//===----------------------------------------------------------------------===// 86 87/// HandlePragmaDirective - The "#pragma" directive has been parsed. Lex the 88/// rest of the pragma, passing it to the registered pragma handlers. 89void Preprocessor::HandlePragmaDirective() { 90 ++NumPragma; 91 92 // Invoke the first level of pragma handlers which reads the namespace id. 93 Token Tok; 94 PragmaHandlers->HandlePragma(*this, Tok); 95 96 // If the pragma handler didn't read the rest of the line, consume it now. 97 if (CurPPLexer && CurPPLexer->ParsingPreprocessorDirective) 98 DiscardUntilEndOfDirective(); 99} 100 101/// Handle_Pragma - Read a _Pragma directive, slice it up, process it, then 102/// return the first token after the directive. The _Pragma token has just 103/// been read into 'Tok'. 104void Preprocessor::Handle_Pragma(Token &Tok) { 105 // Remember the pragma token location. 106 SourceLocation PragmaLoc = Tok.getLocation(); 107 108 // Read the '('. 109 Lex(Tok); 110 if (Tok.isNot(tok::l_paren)) { 111 Diag(PragmaLoc, diag::err__Pragma_malformed); 112 return; 113 } 114 115 // Read the '"..."'. 116 Lex(Tok); 117 if (Tok.isNot(tok::string_literal) && Tok.isNot(tok::wide_string_literal)) { 118 Diag(PragmaLoc, diag::err__Pragma_malformed); 119 return; 120 } 121 122 // Remember the string. 123 std::string StrVal = getSpelling(Tok); 124 125 // Read the ')'. 126 Lex(Tok); 127 if (Tok.isNot(tok::r_paren)) { 128 Diag(PragmaLoc, diag::err__Pragma_malformed); 129 return; 130 } 131 132 SourceLocation RParenLoc = Tok.getLocation(); 133 134 // The _Pragma is lexically sound. Destringize according to C99 6.10.9.1: 135 // "The string literal is destringized by deleting the L prefix, if present, 136 // deleting the leading and trailing double-quotes, replacing each escape 137 // sequence \" by a double-quote, and replacing each escape sequence \\ by a 138 // single backslash." 139 if (StrVal[0] == 'L') // Remove L prefix. 140 StrVal.erase(StrVal.begin()); 141 assert(StrVal[0] == '"' && StrVal[StrVal.size()-1] == '"' && 142 "Invalid string token!"); 143 144 // Remove the front quote, replacing it with a space, so that the pragma 145 // contents appear to have a space before them. 146 StrVal[0] = ' '; 147 148 // Replace the terminating quote with a \n. 149 StrVal[StrVal.size()-1] = '\n'; 150 151 // Remove escaped quotes and escapes. 152 for (unsigned i = 0, e = StrVal.size(); i != e-1; ++i) { 153 if (StrVal[i] == '\\' && 154 (StrVal[i+1] == '\\' || StrVal[i+1] == '"')) { 155 // \\ -> '\' and \" -> '"'. 156 StrVal.erase(StrVal.begin()+i); 157 --e; 158 } 159 } 160 161 // Plop the string (including the newline and trailing null) into a buffer 162 // where we can lex it. 163 Token TmpTok; 164 TmpTok.startToken(); 165 CreateString(&StrVal[0], StrVal.size(), TmpTok); 166 SourceLocation TokLoc = TmpTok.getLocation(); 167 168 // Make and enter a lexer object so that we lex and expand the tokens just 169 // like any others. 170 Lexer *TL = Lexer::Create_PragmaLexer(TokLoc, PragmaLoc, RParenLoc, 171 StrVal.size(), *this); 172 173 EnterSourceFileWithLexer(TL, 0); 174 175 // With everything set up, lex this as a #pragma directive. 176 HandlePragmaDirective(); 177 178 // Finally, return whatever came after the pragma directive. 179 return Lex(Tok); 180} 181 182 183 184/// HandlePragmaOnce - Handle #pragma once. OnceTok is the 'once'. 185/// 186void Preprocessor::HandlePragmaOnce(Token &OnceTok) { 187 if (isInPrimaryFile()) { 188 Diag(OnceTok, diag::pp_pragma_once_in_main_file); 189 return; 190 } 191 192 // Get the current file lexer we're looking at. Ignore _Pragma 'files' etc. 193 // Mark the file as a once-only file now. 194 HeaderInfo.MarkFileIncludeOnce(getCurrentFileLexer()->getFileEntry()); 195} 196 197void Preprocessor::HandlePragmaMark() { 198 assert(CurPPLexer && "No current lexer?"); 199 if (CurLexer) 200 CurLexer->ReadToEndOfLine(); 201 else 202 CurPTHLexer->DiscardToEndOfLine(); 203} 204 205 206/// HandlePragmaPoison - Handle #pragma GCC poison. PoisonTok is the 'poison'. 207/// 208void Preprocessor::HandlePragmaPoison(Token &PoisonTok) { 209 Token Tok; 210 211 while (1) { 212 // Read the next token to poison. While doing this, pretend that we are 213 // skipping while reading the identifier to poison. 214 // This avoids errors on code like: 215 // #pragma GCC poison X 216 // #pragma GCC poison X 217 if (CurPPLexer) CurPPLexer->LexingRawMode = true; 218 LexUnexpandedToken(Tok); 219 if (CurPPLexer) CurPPLexer->LexingRawMode = false; 220 221 // If we reached the end of line, we're done. 222 if (Tok.is(tok::eom)) return; 223 224 // Can only poison identifiers. 225 if (Tok.isNot(tok::identifier)) { 226 Diag(Tok, diag::err_pp_invalid_poison); 227 return; 228 } 229 230 // Look up the identifier info for the token. We disabled identifier lookup 231 // by saying we're skipping contents, so we need to do this manually. 232 IdentifierInfo *II = LookUpIdentifierInfo(Tok); 233 234 // Already poisoned. 235 if (II->isPoisoned()) continue; 236 237 // If this is a macro identifier, emit a warning. 238 if (II->hasMacroDefinition()) 239 Diag(Tok, diag::pp_poisoning_existing_macro); 240 241 // Finally, poison it! 242 II->setIsPoisoned(); 243 } 244} 245 246/// HandlePragmaSystemHeader - Implement #pragma GCC system_header. We know 247/// that the whole directive has been parsed. 248void Preprocessor::HandlePragmaSystemHeader(Token &SysHeaderTok) { 249 if (isInPrimaryFile()) { 250 Diag(SysHeaderTok, diag::pp_pragma_sysheader_in_main_file); 251 return; 252 } 253 254 // Get the current file lexer we're looking at. Ignore _Pragma 'files' etc. 255 PreprocessorLexer *TheLexer = getCurrentFileLexer(); 256 257 // Mark the file as a system header. 258 HeaderInfo.MarkFileSystemHeader(TheLexer->getFileEntry()); 259 260 261 PresumedLoc PLoc = SourceMgr.getPresumedLoc(SysHeaderTok.getLocation()); 262 unsigned FilenameLen = strlen(PLoc.getFilename()); 263 unsigned FilenameID = SourceMgr.getLineTableFilenameID(PLoc.getFilename(), 264 FilenameLen); 265 266 // Emit a line marker. This will change any source locations from this point 267 // forward to realize they are in a system header. 268 // Create a line note with this information. 269 SourceMgr.AddLineNote(SysHeaderTok.getLocation(), PLoc.getLine(), FilenameID, 270 false, false, true, false); 271 272 // Notify the client, if desired, that we are in a new source file. 273 if (Callbacks) 274 Callbacks->FileChanged(SysHeaderTok.getLocation(), 275 PPCallbacks::SystemHeaderPragma, SrcMgr::C_System); 276} 277 278/// HandlePragmaDependency - Handle #pragma GCC dependency "foo" blah. 279/// 280void Preprocessor::HandlePragmaDependency(Token &DependencyTok) { 281 Token FilenameTok; 282 CurPPLexer->LexIncludeFilename(FilenameTok); 283 284 // If the token kind is EOM, the error has already been diagnosed. 285 if (FilenameTok.is(tok::eom)) 286 return; 287 288 // Reserve a buffer to get the spelling. 289 llvm::SmallString<128> FilenameBuffer; 290 FilenameBuffer.resize(FilenameTok.getLength()); 291 292 const char *FilenameStart = &FilenameBuffer[0]; 293 unsigned Len = getSpelling(FilenameTok, FilenameStart); 294 llvm::StringRef Filename(FilenameStart, Len); 295 bool isAngled = 296 GetIncludeFilenameSpelling(FilenameTok.getLocation(), Filename); 297 // If GetIncludeFilenameSpelling set the start ptr to null, there was an 298 // error. 299 if (Filename.empty()) 300 return; 301 302 // Search include directories for this file. 303 const DirectoryLookup *CurDir; 304 const FileEntry *File = LookupFile(Filename, isAngled, 0, CurDir); 305 if (File == 0) { 306 Diag(FilenameTok, diag::err_pp_file_not_found) << Filename; 307 return; 308 } 309 310 const FileEntry *CurFile = getCurrentFileLexer()->getFileEntry(); 311 312 // If this file is older than the file it depends on, emit a diagnostic. 313 if (CurFile && CurFile->getModificationTime() < File->getModificationTime()) { 314 // Lex tokens at the end of the message and include them in the message. 315 std::string Message; 316 Lex(DependencyTok); 317 while (DependencyTok.isNot(tok::eom)) { 318 Message += getSpelling(DependencyTok) + " "; 319 Lex(DependencyTok); 320 } 321 322 Message.erase(Message.end()-1); 323 Diag(FilenameTok, diag::pp_out_of_date_dependency) << Message; 324 } 325} 326 327/// HandlePragmaComment - Handle the microsoft #pragma comment extension. The 328/// syntax is: 329/// #pragma comment(linker, "foo") 330/// 'linker' is one of five identifiers: compiler, exestr, lib, linker, user. 331/// "foo" is a string, which is fully macro expanded, and permits string 332/// concatenation, embedded escape characters etc. See MSDN for more details. 333void Preprocessor::HandlePragmaComment(Token &Tok) { 334 SourceLocation CommentLoc = Tok.getLocation(); 335 Lex(Tok); 336 if (Tok.isNot(tok::l_paren)) { 337 Diag(CommentLoc, diag::err_pragma_comment_malformed); 338 return; 339 } 340 341 // Read the identifier. 342 Lex(Tok); 343 if (Tok.isNot(tok::identifier)) { 344 Diag(CommentLoc, diag::err_pragma_comment_malformed); 345 return; 346 } 347 348 // Verify that this is one of the 5 whitelisted options. 349 // FIXME: warn that 'exestr' is deprecated. 350 const IdentifierInfo *II = Tok.getIdentifierInfo(); 351 if (!II->isStr("compiler") && !II->isStr("exestr") && !II->isStr("lib") && 352 !II->isStr("linker") && !II->isStr("user")) { 353 Diag(Tok.getLocation(), diag::err_pragma_comment_unknown_kind); 354 return; 355 } 356 357 // Read the optional string if present. 358 Lex(Tok); 359 std::string ArgumentString; 360 if (Tok.is(tok::comma)) { 361 Lex(Tok); // eat the comma. 362 363 // We need at least one string. 364 if (Tok.isNot(tok::string_literal)) { 365 Diag(Tok.getLocation(), diag::err_pragma_comment_malformed); 366 return; 367 } 368 369 // String concatenation allows multiple strings, which can even come from 370 // macro expansion. 371 // "foo " "bar" "Baz" 372 llvm::SmallVector<Token, 4> StrToks; 373 while (Tok.is(tok::string_literal)) { 374 StrToks.push_back(Tok); 375 Lex(Tok); 376 } 377 378 // Concatenate and parse the strings. 379 StringLiteralParser Literal(&StrToks[0], StrToks.size(), *this); 380 assert(!Literal.AnyWide && "Didn't allow wide strings in"); 381 if (Literal.hadError) 382 return; 383 if (Literal.Pascal) { 384 Diag(StrToks[0].getLocation(), diag::err_pragma_comment_malformed); 385 return; 386 } 387 388 ArgumentString = std::string(Literal.GetString(), 389 Literal.GetString()+Literal.GetStringLength()); 390 } 391 392 // FIXME: If the kind is "compiler" warn if the string is present (it is 393 // ignored). 394 // FIXME: 'lib' requires a comment string. 395 // FIXME: 'linker' requires a comment string, and has a specific list of 396 // things that are allowable. 397 398 if (Tok.isNot(tok::r_paren)) { 399 Diag(Tok.getLocation(), diag::err_pragma_comment_malformed); 400 return; 401 } 402 Lex(Tok); // eat the r_paren. 403 404 if (Tok.isNot(tok::eom)) { 405 Diag(Tok.getLocation(), diag::err_pragma_comment_malformed); 406 return; 407 } 408 409 // If the pragma is lexically sound, notify any interested PPCallbacks. 410 if (Callbacks) 411 Callbacks->PragmaComment(CommentLoc, II, ArgumentString); 412} 413 414 415 416 417/// AddPragmaHandler - Add the specified pragma handler to the preprocessor. 418/// If 'Namespace' is non-null, then it is a token required to exist on the 419/// pragma line before the pragma string starts, e.g. "STDC" or "GCC". 420void Preprocessor::AddPragmaHandler(const char *Namespace, 421 PragmaHandler *Handler) { 422 PragmaNamespace *InsertNS = PragmaHandlers; 423 424 // If this is specified to be in a namespace, step down into it. 425 if (Namespace) { 426 IdentifierInfo *NSID = getIdentifierInfo(Namespace); 427 428 // If there is already a pragma handler with the name of this namespace, 429 // we either have an error (directive with the same name as a namespace) or 430 // we already have the namespace to insert into. 431 if (PragmaHandler *Existing = PragmaHandlers->FindHandler(NSID)) { 432 InsertNS = Existing->getIfNamespace(); 433 assert(InsertNS != 0 && "Cannot have a pragma namespace and pragma" 434 " handler with the same name!"); 435 } else { 436 // Otherwise, this namespace doesn't exist yet, create and insert the 437 // handler for it. 438 InsertNS = new PragmaNamespace(NSID); 439 PragmaHandlers->AddPragma(InsertNS); 440 } 441 } 442 443 // Check to make sure we don't already have a pragma for this identifier. 444 assert(!InsertNS->FindHandler(Handler->getName()) && 445 "Pragma handler already exists for this identifier!"); 446 InsertNS->AddPragma(Handler); 447} 448 449/// RemovePragmaHandler - Remove the specific pragma handler from the 450/// preprocessor. If \arg Namespace is non-null, then it should be the 451/// namespace that \arg Handler was added to. It is an error to remove 452/// a handler that has not been registered. 453void Preprocessor::RemovePragmaHandler(const char *Namespace, 454 PragmaHandler *Handler) { 455 PragmaNamespace *NS = PragmaHandlers; 456 457 // If this is specified to be in a namespace, step down into it. 458 if (Namespace) { 459 IdentifierInfo *NSID = getIdentifierInfo(Namespace); 460 PragmaHandler *Existing = PragmaHandlers->FindHandler(NSID); 461 assert(Existing && "Namespace containing handler does not exist!"); 462 463 NS = Existing->getIfNamespace(); 464 assert(NS && "Invalid namespace, registered as a regular pragma handler!"); 465 } 466 467 NS->RemovePragmaHandler(Handler); 468 469 // If this is a non-default namespace and it is now empty, remove 470 // it. 471 if (NS != PragmaHandlers && NS->IsEmpty()) 472 PragmaHandlers->RemovePragmaHandler(NS); 473} 474 475namespace { 476/// PragmaOnceHandler - "#pragma once" marks the file as atomically included. 477struct PragmaOnceHandler : public PragmaHandler { 478 PragmaOnceHandler(const IdentifierInfo *OnceID) : PragmaHandler(OnceID) {} 479 virtual void HandlePragma(Preprocessor &PP, Token &OnceTok) { 480 PP.CheckEndOfDirective("pragma once"); 481 PP.HandlePragmaOnce(OnceTok); 482 } 483}; 484 485/// PragmaMarkHandler - "#pragma mark ..." is ignored by the compiler, and the 486/// rest of the line is not lexed. 487struct PragmaMarkHandler : public PragmaHandler { 488 PragmaMarkHandler(const IdentifierInfo *MarkID) : PragmaHandler(MarkID) {} 489 virtual void HandlePragma(Preprocessor &PP, Token &MarkTok) { 490 PP.HandlePragmaMark(); 491 } 492}; 493 494/// PragmaPoisonHandler - "#pragma poison x" marks x as not usable. 495struct PragmaPoisonHandler : public PragmaHandler { 496 PragmaPoisonHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} 497 virtual void HandlePragma(Preprocessor &PP, Token &PoisonTok) { 498 PP.HandlePragmaPoison(PoisonTok); 499 } 500}; 501 502/// PragmaSystemHeaderHandler - "#pragma system_header" marks the current file 503/// as a system header, which silences warnings in it. 504struct PragmaSystemHeaderHandler : public PragmaHandler { 505 PragmaSystemHeaderHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} 506 virtual void HandlePragma(Preprocessor &PP, Token &SHToken) { 507 PP.HandlePragmaSystemHeader(SHToken); 508 PP.CheckEndOfDirective("pragma"); 509 } 510}; 511struct PragmaDependencyHandler : public PragmaHandler { 512 PragmaDependencyHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} 513 virtual void HandlePragma(Preprocessor &PP, Token &DepToken) { 514 PP.HandlePragmaDependency(DepToken); 515 } 516}; 517 518/// PragmaDiagnosticHandler - e.g. '#pragma GCC diagnostic ignored "-Wformat"' 519/// Since clang's diagnostic supports extended functionality beyond GCC's 520/// the constructor takes a clangMode flag to tell it whether or not to allow 521/// clang's extended functionality, or whether to reject it. 522struct PragmaDiagnosticHandler : public PragmaHandler { 523private: 524 const bool ClangMode; 525public: 526 PragmaDiagnosticHandler(const IdentifierInfo *ID, 527 const bool clangMode) : PragmaHandler(ID), 528 ClangMode(clangMode) {} 529 virtual void HandlePragma(Preprocessor &PP, Token &DiagToken) { 530 Token Tok; 531 PP.LexUnexpandedToken(Tok); 532 if (Tok.isNot(tok::identifier)) { 533 unsigned Diag = ClangMode ? diag::warn_pragma_diagnostic_clang_invalid 534 : diag::warn_pragma_diagnostic_gcc_invalid; 535 PP.Diag(Tok, Diag); 536 return; 537 } 538 IdentifierInfo *II = Tok.getIdentifierInfo(); 539 540 diag::Mapping Map; 541 if (II->isStr("warning")) 542 Map = diag::MAP_WARNING; 543 else if (II->isStr("error")) 544 Map = diag::MAP_ERROR; 545 else if (II->isStr("ignored")) 546 Map = diag::MAP_IGNORE; 547 else if (II->isStr("fatal")) 548 Map = diag::MAP_FATAL; 549 else if (ClangMode) { 550 if (II->isStr("pop")) { 551 if (!PP.getDiagnostics().popMappings()) 552 PP.Diag(Tok, diag::warn_pragma_diagnostic_clang_cannot_ppp); 553 return; 554 } 555 556 if (II->isStr("push")) { 557 PP.getDiagnostics().pushMappings(); 558 return; 559 } 560 561 PP.Diag(Tok, diag::warn_pragma_diagnostic_clang_invalid); 562 return; 563 } else { 564 PP.Diag(Tok, diag::warn_pragma_diagnostic_gcc_invalid); 565 return; 566 } 567 568 PP.LexUnexpandedToken(Tok); 569 570 // We need at least one string. 571 if (Tok.isNot(tok::string_literal)) { 572 PP.Diag(Tok.getLocation(), diag::warn_pragma_diagnostic_invalid_token); 573 return; 574 } 575 576 // String concatenation allows multiple strings, which can even come from 577 // macro expansion. 578 // "foo " "bar" "Baz" 579 llvm::SmallVector<Token, 4> StrToks; 580 while (Tok.is(tok::string_literal)) { 581 StrToks.push_back(Tok); 582 PP.LexUnexpandedToken(Tok); 583 } 584 585 if (Tok.isNot(tok::eom)) { 586 PP.Diag(Tok.getLocation(), diag::warn_pragma_diagnostic_invalid_token); 587 return; 588 } 589 590 // Concatenate and parse the strings. 591 StringLiteralParser Literal(&StrToks[0], StrToks.size(), PP); 592 assert(!Literal.AnyWide && "Didn't allow wide strings in"); 593 if (Literal.hadError) 594 return; 595 if (Literal.Pascal) { 596 unsigned Diag = ClangMode ? diag::warn_pragma_diagnostic_clang_invalid 597 : diag::warn_pragma_diagnostic_gcc_invalid; 598 PP.Diag(Tok, Diag); 599 return; 600 } 601 602 std::string WarningName(Literal.GetString(), 603 Literal.GetString()+Literal.GetStringLength()); 604 605 if (WarningName.size() < 3 || WarningName[0] != '-' || 606 WarningName[1] != 'W') { 607 PP.Diag(StrToks[0].getLocation(), 608 diag::warn_pragma_diagnostic_invalid_option); 609 return; 610 } 611 612 if (PP.getDiagnostics().setDiagnosticGroupMapping(WarningName.c_str()+2, 613 Map)) 614 PP.Diag(StrToks[0].getLocation(), 615 diag::warn_pragma_diagnostic_unknown_warning) << WarningName; 616 } 617}; 618 619/// PragmaCommentHandler - "#pragma comment ...". 620struct PragmaCommentHandler : public PragmaHandler { 621 PragmaCommentHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} 622 virtual void HandlePragma(Preprocessor &PP, Token &CommentTok) { 623 PP.HandlePragmaComment(CommentTok); 624 } 625}; 626 627// Pragma STDC implementations. 628 629enum STDCSetting { 630 STDC_ON, STDC_OFF, STDC_DEFAULT, STDC_INVALID 631}; 632 633static STDCSetting LexOnOffSwitch(Preprocessor &PP) { 634 Token Tok; 635 PP.LexUnexpandedToken(Tok); 636 637 if (Tok.isNot(tok::identifier)) { 638 PP.Diag(Tok, diag::ext_stdc_pragma_syntax); 639 return STDC_INVALID; 640 } 641 IdentifierInfo *II = Tok.getIdentifierInfo(); 642 STDCSetting Result; 643 if (II->isStr("ON")) 644 Result = STDC_ON; 645 else if (II->isStr("OFF")) 646 Result = STDC_OFF; 647 else if (II->isStr("DEFAULT")) 648 Result = STDC_DEFAULT; 649 else { 650 PP.Diag(Tok, diag::ext_stdc_pragma_syntax); 651 return STDC_INVALID; 652 } 653 654 // Verify that this is followed by EOM. 655 PP.LexUnexpandedToken(Tok); 656 if (Tok.isNot(tok::eom)) 657 PP.Diag(Tok, diag::ext_stdc_pragma_syntax_eom); 658 return Result; 659} 660 661/// PragmaSTDC_FP_CONTRACTHandler - "#pragma STDC FP_CONTRACT ...". 662struct PragmaSTDC_FP_CONTRACTHandler : public PragmaHandler { 663 PragmaSTDC_FP_CONTRACTHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} 664 virtual void HandlePragma(Preprocessor &PP, Token &Tok) { 665 // We just ignore the setting of FP_CONTRACT. Since we don't do contractions 666 // at all, our default is OFF and setting it to ON is an optimization hint 667 // we can safely ignore. When we support -ffma or something, we would need 668 // to diagnose that we are ignoring FMA. 669 LexOnOffSwitch(PP); 670 } 671}; 672 673/// PragmaSTDC_FENV_ACCESSHandler - "#pragma STDC FENV_ACCESS ...". 674struct PragmaSTDC_FENV_ACCESSHandler : public PragmaHandler { 675 PragmaSTDC_FENV_ACCESSHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} 676 virtual void HandlePragma(Preprocessor &PP, Token &Tok) { 677 if (LexOnOffSwitch(PP) == STDC_ON) 678 PP.Diag(Tok, diag::warn_stdc_fenv_access_not_supported); 679 } 680}; 681 682/// PragmaSTDC_CX_LIMITED_RANGEHandler - "#pragma STDC CX_LIMITED_RANGE ...". 683struct PragmaSTDC_CX_LIMITED_RANGEHandler : public PragmaHandler { 684 PragmaSTDC_CX_LIMITED_RANGEHandler(const IdentifierInfo *ID) 685 : PragmaHandler(ID) {} 686 virtual void HandlePragma(Preprocessor &PP, Token &Tok) { 687 LexOnOffSwitch(PP); 688 } 689}; 690 691/// PragmaSTDC_UnknownHandler - "#pragma STDC ...". 692struct PragmaSTDC_UnknownHandler : public PragmaHandler { 693 PragmaSTDC_UnknownHandler() : PragmaHandler(0) {} 694 virtual void HandlePragma(Preprocessor &PP, Token &UnknownTok) { 695 // C99 6.10.6p2, unknown forms are not allowed. 696 PP.Diag(UnknownTok, diag::ext_stdc_pragma_ignored); 697 } 698}; 699 700} // end anonymous namespace 701 702 703/// RegisterBuiltinPragmas - Install the standard preprocessor pragmas: 704/// #pragma GCC poison/system_header/dependency and #pragma once. 705void Preprocessor::RegisterBuiltinPragmas() { 706 AddPragmaHandler(0, new PragmaOnceHandler(getIdentifierInfo("once"))); 707 AddPragmaHandler(0, new PragmaMarkHandler(getIdentifierInfo("mark"))); 708 709 // #pragma GCC ... 710 AddPragmaHandler("GCC", new PragmaPoisonHandler(getIdentifierInfo("poison"))); 711 AddPragmaHandler("GCC", new PragmaSystemHeaderHandler( 712 getIdentifierInfo("system_header"))); 713 AddPragmaHandler("GCC", new PragmaDependencyHandler( 714 getIdentifierInfo("dependency"))); 715 AddPragmaHandler("GCC", new PragmaDiagnosticHandler( 716 getIdentifierInfo("diagnostic"), 717 false)); 718 // #pragma clang ... 719 AddPragmaHandler("clang", new PragmaPoisonHandler( 720 getIdentifierInfo("poison"))); 721 AddPragmaHandler("clang", new PragmaSystemHeaderHandler( 722 getIdentifierInfo("system_header"))); 723 AddPragmaHandler("clang", new PragmaDependencyHandler( 724 getIdentifierInfo("dependency"))); 725 AddPragmaHandler("clang", new PragmaDiagnosticHandler( 726 getIdentifierInfo("diagnostic"), 727 true)); 728 729 AddPragmaHandler("STDC", new PragmaSTDC_FP_CONTRACTHandler( 730 getIdentifierInfo("FP_CONTRACT"))); 731 AddPragmaHandler("STDC", new PragmaSTDC_FENV_ACCESSHandler( 732 getIdentifierInfo("FENV_ACCESS"))); 733 AddPragmaHandler("STDC", new PragmaSTDC_CX_LIMITED_RANGEHandler( 734 getIdentifierInfo("CX_LIMITED_RANGE"))); 735 AddPragmaHandler("STDC", new PragmaSTDC_UnknownHandler()); 736 737 // MS extensions. 738 if (Features.Microsoft) 739 AddPragmaHandler(0, new PragmaCommentHandler(getIdentifierInfo("comment"))); 740} 741