//===--- PPDirectives.cpp - Directive Handling for Preprocessor -----------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// /// /// \file /// \brief Implements # directive processing for the Preprocessor. /// //===----------------------------------------------------------------------===// #include "clang/Lex/Preprocessor.h" #include "clang/Basic/FileManager.h" #include "clang/Basic/SourceManager.h" #include "clang/Lex/CodeCompletionHandler.h" #include "clang/Lex/HeaderSearch.h" #include "clang/Lex/HeaderSearchOptions.h" #include "clang/Lex/LexDiagnostic.h" #include "clang/Lex/LiteralSupport.h" #include "clang/Lex/MacroInfo.h" #include "clang/Lex/ModuleLoader.h" #include "clang/Lex/Pragma.h" #include "llvm/ADT/APInt.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/SaveAndRestore.h" using namespace clang; //===----------------------------------------------------------------------===// // Utility Methods for Preprocessor Directive Handling. //===----------------------------------------------------------------------===// MacroInfo *Preprocessor::AllocateMacroInfo() { MacroInfoChain *MIChain; if (MICache) { MIChain = MICache; MICache = MICache->Next; } else { MIChain = BP.Allocate(); } MIChain->Next = MIChainHead; MIChain->Prev = nullptr; if (MIChainHead) MIChainHead->Prev = MIChain; MIChainHead = MIChain; return &(MIChain->MI); } MacroInfo *Preprocessor::AllocateMacroInfo(SourceLocation L) { MacroInfo *MI = AllocateMacroInfo(); new (MI) MacroInfo(L); return MI; } MacroInfo *Preprocessor::AllocateDeserializedMacroInfo(SourceLocation L, unsigned SubModuleID) { static_assert(llvm::AlignOf::Alignment >= sizeof(SubModuleID), "alignment for MacroInfo is less than the ID"); DeserializedMacroInfoChain *MIChain = BP.Allocate(); MIChain->Next = DeserialMIChainHead; DeserialMIChainHead = MIChain; MacroInfo *MI = &MIChain->MI; new (MI) MacroInfo(L); MI->FromASTFile = true; MI->setOwningModuleID(SubModuleID); return MI; } DefMacroDirective * Preprocessor::AllocateDefMacroDirective(MacroInfo *MI, SourceLocation Loc, bool isImported) { DefMacroDirective *MD = BP.Allocate(); new (MD) DefMacroDirective(MI, Loc, isImported); return MD; } UndefMacroDirective * Preprocessor::AllocateUndefMacroDirective(SourceLocation UndefLoc) { UndefMacroDirective *MD = BP.Allocate(); new (MD) UndefMacroDirective(UndefLoc); return MD; } VisibilityMacroDirective * Preprocessor::AllocateVisibilityMacroDirective(SourceLocation Loc, bool isPublic) { VisibilityMacroDirective *MD = BP.Allocate(); new (MD) VisibilityMacroDirective(Loc, isPublic); return MD; } /// \brief Release the specified MacroInfo to be reused for allocating /// new MacroInfo objects. void Preprocessor::ReleaseMacroInfo(MacroInfo *MI) { MacroInfoChain *MIChain = (MacroInfoChain *)MI; if (MacroInfoChain *Prev = MIChain->Prev) { MacroInfoChain *Next = MIChain->Next; Prev->Next = Next; if (Next) Next->Prev = Prev; } else { assert(MIChainHead == MIChain); MIChainHead = MIChain->Next; MIChainHead->Prev = nullptr; } MIChain->Next = MICache; MICache = MIChain; MI->Destroy(); } /// \brief Read and discard all tokens remaining on the current line until /// the tok::eod token is found. void Preprocessor::DiscardUntilEndOfDirective() { Token Tmp; do { LexUnexpandedToken(Tmp); assert(Tmp.isNot(tok::eof) && "EOF seen while discarding directive tokens"); } while (Tmp.isNot(tok::eod)); } bool Preprocessor::CheckMacroName(Token &MacroNameTok, char isDefineUndef) { // Missing macro name? if (MacroNameTok.is(tok::eod)) return Diag(MacroNameTok, diag::err_pp_missing_macro_name); IdentifierInfo *II = MacroNameTok.getIdentifierInfo(); if (!II) { bool Invalid = false; std::string Spelling = getSpelling(MacroNameTok, &Invalid); if (Invalid) return Diag(MacroNameTok, diag::err_pp_macro_not_identifier); II = getIdentifierInfo(Spelling); if (!II->isCPlusPlusOperatorKeyword()) return Diag(MacroNameTok, diag::err_pp_macro_not_identifier); // C++ 2.5p2: Alternative tokens behave the same as its primary token // except for their spellings. Diag(MacroNameTok, getLangOpts().MicrosoftExt ? diag::ext_pp_operator_used_as_macro_name : diag::err_pp_operator_used_as_macro_name) << II << MacroNameTok.getKind(); // Allow #defining |and| and friends for Microsoft compatibility or // recovery when legacy C headers are included in C++. MacroNameTok.setIdentifierInfo(II); } if (isDefineUndef && II->getPPKeywordID() == tok::pp_defined) { // Error if defining "defined": C99 6.10.8/4, C++ [cpp.predefined]p4. return Diag(MacroNameTok, diag::err_defined_macro_name); } if (isDefineUndef == 2 && II->hasMacroDefinition() && getMacroInfo(II)->isBuiltinMacro()) { // Warn if undefining "__LINE__" and other builtins, per C99 6.10.8/4 // and C++ [cpp.predefined]p4], but allow it as an extension. Diag(MacroNameTok, diag::ext_pp_undef_builtin_macro); } // Okay, we got a good identifier. return false; } /// \brief Lex and validate a macro name, which occurs after a /// \#define or \#undef. /// /// This sets the token kind to eod and discards the rest /// of the macro line if the macro name is invalid. \p isDefineUndef is 1 if /// this is due to a a \#define, 2 if \#undef directive, 0 if it is something /// else (e.g. \#ifdef). void Preprocessor::ReadMacroName(Token &MacroNameTok, char isDefineUndef) { // Read the token, don't allow macro expansion on it. LexUnexpandedToken(MacroNameTok); if (MacroNameTok.is(tok::code_completion)) { if (CodeComplete) CodeComplete->CodeCompleteMacroName(isDefineUndef == 1); setCodeCompletionReached(); LexUnexpandedToken(MacroNameTok); } if (!CheckMacroName(MacroNameTok, isDefineUndef)) return; // Invalid macro name, read and discard the rest of the line and set the // token kind to tok::eod if necessary. if (MacroNameTok.isNot(tok::eod)) { MacroNameTok.setKind(tok::eod); DiscardUntilEndOfDirective(); } } /// \brief Ensure that the next token is a tok::eod token. /// /// If not, emit a diagnostic and consume up until the eod. If EnableMacros is /// true, then we consider macros that expand to zero tokens as being ok. void Preprocessor::CheckEndOfDirective(const char *DirType, bool EnableMacros) { Token Tmp; // Lex unexpanded tokens for most directives: macros might expand to zero // tokens, causing us to miss diagnosing invalid lines. Some directives (like // #line) allow empty macros. if (EnableMacros) Lex(Tmp); else LexUnexpandedToken(Tmp); // There should be no tokens after the directive, but we allow them as an // extension. while (Tmp.is(tok::comment)) // Skip comments in -C mode. LexUnexpandedToken(Tmp); if (Tmp.isNot(tok::eod)) { // Add a fixit in GNU/C99/C++ mode. Don't offer a fixit for strict-C89, // or if this is a macro-style preprocessing directive, because it is more // trouble than it is worth to insert /**/ and check that there is no /**/ // in the range also. FixItHint Hint; if ((LangOpts.GNUMode || LangOpts.C99 || LangOpts.CPlusPlus) && !CurTokenLexer) Hint = FixItHint::CreateInsertion(Tmp.getLocation(),"//"); Diag(Tmp, diag::ext_pp_extra_tokens_at_eol) << DirType << Hint; DiscardUntilEndOfDirective(); } } /// SkipExcludedConditionalBlock - We just read a \#if or related directive and /// decided that the subsequent tokens are in the \#if'd out portion of the /// file. Lex the rest of the file, until we see an \#endif. If /// FoundNonSkipPortion is true, then we have already emitted code for part of /// this \#if directive, so \#else/\#elif blocks should never be entered. /// If ElseOk is true, then \#else directives are ok, if not, then we have /// already seen one so a \#else directive is a duplicate. When this returns, /// the caller can lex the first valid token. void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc, bool FoundNonSkipPortion, bool FoundElse, SourceLocation ElseLoc) { ++NumSkipped; assert(!CurTokenLexer && CurPPLexer && "Lexing a macro, not a file?"); CurPPLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false, FoundNonSkipPortion, FoundElse); if (CurPTHLexer) { PTHSkipExcludedConditionalBlock(); return; } // Enter raw mode to disable identifier lookup (and thus macro expansion), // disabling warnings, etc. CurPPLexer->LexingRawMode = true; Token Tok; while (1) { CurLexer->Lex(Tok); if (Tok.is(tok::code_completion)) { if (CodeComplete) CodeComplete->CodeCompleteInConditionalExclusion(); setCodeCompletionReached(); continue; } // If this is the end of the buffer, we have an error. if (Tok.is(tok::eof)) { // Emit errors for each unterminated conditional on the stack, including // the current one. while (!CurPPLexer->ConditionalStack.empty()) { if (CurLexer->getFileLoc() != CodeCompletionFileLoc) Diag(CurPPLexer->ConditionalStack.back().IfLoc, diag::err_pp_unterminated_conditional); CurPPLexer->ConditionalStack.pop_back(); } // Just return and let the caller lex after this #include. break; } // If this token is not a preprocessor directive, just skip it. if (Tok.isNot(tok::hash) || !Tok.isAtStartOfLine()) continue; // We just parsed a # character at the start of a line, so we're in // directive mode. Tell the lexer this so any newlines we see will be // converted into an EOD token (this terminates the macro). CurPPLexer->ParsingPreprocessorDirective = true; if (CurLexer) CurLexer->SetKeepWhitespaceMode(false); // Read the next token, the directive flavor. LexUnexpandedToken(Tok); // If this isn't an identifier directive (e.g. is "# 1\n" or "#\n", or // something bogus), skip it. if (Tok.isNot(tok::raw_identifier)) { CurPPLexer->ParsingPreprocessorDirective = false; // Restore comment saving mode. if (CurLexer) CurLexer->resetExtendedTokenMode(); continue; } // If the first letter isn't i or e, it isn't intesting to us. We know that // this is safe in the face of spelling differences, because there is no way // to spell an i/e in a strange way that is another letter. Skipping this // allows us to avoid looking up the identifier info for #define/#undef and // other common directives. StringRef RI = Tok.getRawIdentifier(); char FirstChar = RI[0]; if (FirstChar >= 'a' && FirstChar <= 'z' && FirstChar != 'i' && FirstChar != 'e') { CurPPLexer->ParsingPreprocessorDirective = false; // Restore comment saving mode. if (CurLexer) CurLexer->resetExtendedTokenMode(); continue; } // Get the identifier name without trigraphs or embedded newlines. Note // that we can't use Tok.getIdentifierInfo() because its lookup is disabled // when skipping. char DirectiveBuf[20]; StringRef Directive; if (!Tok.needsCleaning() && RI.size() < 20) { Directive = RI; } else { std::string DirectiveStr = getSpelling(Tok); unsigned IdLen = DirectiveStr.size(); if (IdLen >= 20) { CurPPLexer->ParsingPreprocessorDirective = false; // Restore comment saving mode. if (CurLexer) CurLexer->resetExtendedTokenMode(); continue; } memcpy(DirectiveBuf, &DirectiveStr[0], IdLen); Directive = StringRef(DirectiveBuf, IdLen); } if (Directive.startswith("if")) { StringRef Sub = Directive.substr(2); if (Sub.empty() || // "if" Sub == "def" || // "ifdef" Sub == "ndef") { // "ifndef" // We know the entire #if/#ifdef/#ifndef block will be skipped, don't // bother parsing the condition. DiscardUntilEndOfDirective(); CurPPLexer->pushConditionalLevel(Tok.getLocation(), /*wasskipping*/true, /*foundnonskip*/false, /*foundelse*/false); } } else if (Directive[0] == 'e') { StringRef Sub = Directive.substr(1); if (Sub == "ndif") { // "endif" PPConditionalInfo CondInfo; CondInfo.WasSkipping = true; // Silence bogus warning. bool InCond = CurPPLexer->popConditionalLevel(CondInfo); (void)InCond; // Silence warning in no-asserts mode. assert(!InCond && "Can't be skipping if not in a conditional!"); // If we popped the outermost skipping block, we're done skipping! if (!CondInfo.WasSkipping) { // Restore the value of LexingRawMode so that trailing comments // are handled correctly, if we've reached the outermost block. CurPPLexer->LexingRawMode = false; CheckEndOfDirective("endif"); CurPPLexer->LexingRawMode = true; if (Callbacks) Callbacks->Endif(Tok.getLocation(), CondInfo.IfLoc); break; } else { DiscardUntilEndOfDirective(); } } else if (Sub == "lse") { // "else". // #else directive in a skipping conditional. If not in some other // skipping conditional, and if #else hasn't already been seen, enter it // as a non-skipping conditional. PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel(); // If this is a #else with a #else before it, report the error. if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_else_after_else); // Note that we've seen a #else in this conditional. CondInfo.FoundElse = true; // If the conditional is at the top level, and the #if block wasn't // entered, enter the #else block now. if (!CondInfo.WasSkipping && !CondInfo.FoundNonSkip) { CondInfo.FoundNonSkip = true; // Restore the value of LexingRawMode so that trailing comments // are handled correctly. CurPPLexer->LexingRawMode = false; CheckEndOfDirective("else"); CurPPLexer->LexingRawMode = true; if (Callbacks) Callbacks->Else(Tok.getLocation(), CondInfo.IfLoc); break; } else { DiscardUntilEndOfDirective(); // C99 6.10p4. } } else if (Sub == "lif") { // "elif". PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel(); // If this is a #elif with a #else before it, report the error. if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_elif_after_else); // If this is in a skipping block or if we're already handled this #if // block, don't bother parsing the condition. if (CondInfo.WasSkipping || CondInfo.FoundNonSkip) { DiscardUntilEndOfDirective(); } else { const SourceLocation CondBegin = CurPPLexer->getSourceLocation(); // Restore the value of LexingRawMode so that identifiers are // looked up, etc, inside the #elif expression. assert(CurPPLexer->LexingRawMode && "We have to be skipping here!"); CurPPLexer->LexingRawMode = false; IdentifierInfo *IfNDefMacro = nullptr; const bool CondValue = EvaluateDirectiveExpression(IfNDefMacro); CurPPLexer->LexingRawMode = true; if (Callbacks) { const SourceLocation CondEnd = CurPPLexer->getSourceLocation(); Callbacks->Elif(Tok.getLocation(), SourceRange(CondBegin, CondEnd), (CondValue ? PPCallbacks::CVK_True : PPCallbacks::CVK_False), CondInfo.IfLoc); } // If this condition is true, enter it! if (CondValue) { CondInfo.FoundNonSkip = true; break; } } } } CurPPLexer->ParsingPreprocessorDirective = false; // Restore comment saving mode. if (CurLexer) CurLexer->resetExtendedTokenMode(); } // Finally, if we are out of the conditional (saw an #endif or ran off the end // of the file, just stop skipping and return to lexing whatever came after // the #if block. CurPPLexer->LexingRawMode = false; if (Callbacks) { SourceLocation BeginLoc = ElseLoc.isValid() ? ElseLoc : IfTokenLoc; Callbacks->SourceRangeSkipped(SourceRange(BeginLoc, Tok.getLocation())); } } void Preprocessor::PTHSkipExcludedConditionalBlock() { while (1) { assert(CurPTHLexer); assert(CurPTHLexer->LexingRawMode == false); // Skip to the next '#else', '#elif', or #endif. if (CurPTHLexer->SkipBlock()) { // We have reached an #endif. Both the '#' and 'endif' tokens // have been consumed by the PTHLexer. Just pop off the condition level. PPConditionalInfo CondInfo; bool InCond = CurPTHLexer->popConditionalLevel(CondInfo); (void)InCond; // Silence warning in no-asserts mode. assert(!InCond && "Can't be skipping if not in a conditional!"); break; } // We have reached a '#else' or '#elif'. Lex the next token to get // the directive flavor. Token Tok; LexUnexpandedToken(Tok); // We can actually look up the IdentifierInfo here since we aren't in // raw mode. tok::PPKeywordKind K = Tok.getIdentifierInfo()->getPPKeywordID(); if (K == tok::pp_else) { // #else: Enter the else condition. We aren't in a nested condition // since we skip those. We're always in the one matching the last // blocked we skipped. PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel(); // Note that we've seen a #else in this conditional. CondInfo.FoundElse = true; // If the #if block wasn't entered then enter the #else block now. if (!CondInfo.FoundNonSkip) { CondInfo.FoundNonSkip = true; // Scan until the eod token. CurPTHLexer->ParsingPreprocessorDirective = true; DiscardUntilEndOfDirective(); CurPTHLexer->ParsingPreprocessorDirective = false; break; } // Otherwise skip this block. continue; } assert(K == tok::pp_elif); PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel(); // If this is a #elif with a #else before it, report the error. if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_elif_after_else); // If this is in a skipping block or if we're already handled this #if // block, don't bother parsing the condition. We just skip this block. if (CondInfo.FoundNonSkip) continue; // Evaluate the condition of the #elif. IdentifierInfo *IfNDefMacro = nullptr; CurPTHLexer->ParsingPreprocessorDirective = true; bool ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro); CurPTHLexer->ParsingPreprocessorDirective = false; // If this condition is true, enter it! if (ShouldEnter) { CondInfo.FoundNonSkip = true; break; } // Otherwise, skip this block and go to the next one. continue; } } Module *Preprocessor::getModuleForLocation(SourceLocation FilenameLoc) { ModuleMap &ModMap = HeaderInfo.getModuleMap(); if (SourceMgr.isInMainFile(FilenameLoc)) { if (Module *CurMod = getCurrentModule()) return CurMod; // Compiling a module. return HeaderInfo.getModuleMap().SourceModule; // Compiling a source. } // Try to determine the module of the include directive. // FIXME: Look into directly passing the FileEntry from LookupFile instead. FileID IDOfIncl = SourceMgr.getFileID(SourceMgr.getExpansionLoc(FilenameLoc)); if (const FileEntry *EntryOfIncl = SourceMgr.getFileEntryForID(IDOfIncl)) { // The include comes from a file. return ModMap.findModuleForHeader(EntryOfIncl).getModule(); } else { // The include does not come from a file, // so it is probably a module compilation. return getCurrentModule(); } } const FileEntry *Preprocessor::LookupFile( SourceLocation FilenameLoc, StringRef Filename, bool isAngled, const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir, SmallVectorImpl *SearchPath, SmallVectorImpl *RelativePath, ModuleMap::KnownHeader *SuggestedModule, bool SkipCache) { // If the header lookup mechanism may be relative to the current inclusion // stack, record the parent #includes. SmallVector Includers; if (!FromDir) { FileID FID = getCurrentFileLexer()->getFileID(); const FileEntry *FileEnt = SourceMgr.getFileEntryForID(FID); // If there is no file entry associated with this file, it must be the // predefines buffer. Any other file is not lexed with a normal lexer, so // it won't be scanned for preprocessor directives. If we have the // predefines buffer, resolve #include references (which come from the // -include command line argument) as if they came from the main file, this // affects file lookup etc. if (!FileEnt) FileEnt = SourceMgr.getFileEntryForID(SourceMgr.getMainFileID()); if (FileEnt) Includers.push_back(FileEnt); // MSVC searches the current include stack from top to bottom for // headers included by quoted include directives. // See: http://msdn.microsoft.com/en-us/library/36k2cdd4.aspx if (LangOpts.MSVCCompat && !isAngled) { for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) { IncludeStackInfo &ISEntry = IncludeMacroStack[e - i - 1]; if (IsFileLexer(ISEntry)) if ((FileEnt = SourceMgr.getFileEntryForID( ISEntry.ThePPLexer->getFileID()))) Includers.push_back(FileEnt); } } } // Do a standard file entry lookup. CurDir = CurDirLookup; const FileEntry *FE = HeaderInfo.LookupFile( Filename, FilenameLoc, isAngled, FromDir, CurDir, Includers, SearchPath, RelativePath, SuggestedModule, SkipCache); if (FE) { if (SuggestedModule && !LangOpts.AsmPreprocessor) HeaderInfo.getModuleMap().diagnoseHeaderInclusion( getModuleForLocation(FilenameLoc), FilenameLoc, Filename, FE); return FE; } const FileEntry *CurFileEnt; // Otherwise, see if this is a subframework header. If so, this is relative // to one of the headers on the #include stack. Walk the list of the current // headers on the #include stack and pass them to HeaderInfo. if (IsFileLexer()) { if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID()))) { if ((FE = HeaderInfo.LookupSubframeworkHeader(Filename, CurFileEnt, SearchPath, RelativePath, SuggestedModule))) { if (SuggestedModule && !LangOpts.AsmPreprocessor) HeaderInfo.getModuleMap().diagnoseHeaderInclusion( getModuleForLocation(FilenameLoc), FilenameLoc, Filename, FE); return FE; } } } for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) { IncludeStackInfo &ISEntry = IncludeMacroStack[e-i-1]; if (IsFileLexer(ISEntry)) { if ((CurFileEnt = SourceMgr.getFileEntryForID(ISEntry.ThePPLexer->getFileID()))) { if ((FE = HeaderInfo.LookupSubframeworkHeader( Filename, CurFileEnt, SearchPath, RelativePath, SuggestedModule))) { if (SuggestedModule && !LangOpts.AsmPreprocessor) HeaderInfo.getModuleMap().diagnoseHeaderInclusion( getModuleForLocation(FilenameLoc), FilenameLoc, Filename, FE); return FE; } } } } // Otherwise, we really couldn't find the file. return nullptr; } //===----------------------------------------------------------------------===// // Preprocessor Directive Handling. //===----------------------------------------------------------------------===// class Preprocessor::ResetMacroExpansionHelper { public: ResetMacroExpansionHelper(Preprocessor *pp) : PP(pp), save(pp->DisableMacroExpansion) { if (pp->MacroExpansionInDirectivesOverride) pp->DisableMacroExpansion = false; } ~ResetMacroExpansionHelper() { PP->DisableMacroExpansion = save; } private: Preprocessor *PP; bool save; }; /// HandleDirective - This callback is invoked when the lexer sees a # token /// at the start of a line. This consumes the directive, modifies the /// lexer/preprocessor state, and advances the lexer(s) so that the next token /// read is the correct one. void Preprocessor::HandleDirective(Token &Result) { // FIXME: Traditional: # with whitespace before it not recognized by K&R? // We just parsed a # character at the start of a line, so we're in directive // mode. Tell the lexer this so any newlines we see will be converted into an // EOD token (which terminates the directive). CurPPLexer->ParsingPreprocessorDirective = true; if (CurLexer) CurLexer->SetKeepWhitespaceMode(false); bool ImmediatelyAfterTopLevelIfndef = CurPPLexer->MIOpt.getImmediatelyAfterTopLevelIfndef(); CurPPLexer->MIOpt.resetImmediatelyAfterTopLevelIfndef(); ++NumDirectives; // We are about to read a token. For the multiple-include optimization FA to // work, we have to remember if we had read any tokens *before* this // pp-directive. bool ReadAnyTokensBeforeDirective =CurPPLexer->MIOpt.getHasReadAnyTokensVal(); // Save the '#' token in case we need to return it later. Token SavedHash = Result; // Read the next token, the directive flavor. This isn't expanded due to // C99 6.10.3p8. LexUnexpandedToken(Result); // C99 6.10.3p11: Is this preprocessor directive in macro invocation? e.g.: // #define A(x) #x // A(abc // #warning blah // def) // If so, the user is relying on undefined behavior, emit a diagnostic. Do // not support this for #include-like directives, since that can result in // terrible diagnostics, and does not work in GCC. if (InMacroArgs) { if (IdentifierInfo *II = Result.getIdentifierInfo()) { switch (II->getPPKeywordID()) { case tok::pp_include: case tok::pp_import: case tok::pp_include_next: case tok::pp___include_macros: Diag(Result, diag::err_embedded_include) << II->getName(); DiscardUntilEndOfDirective(); return; default: break; } } Diag(Result, diag::ext_embedded_directive); } // Temporarily enable macro expansion if set so // and reset to previous state when returning from this function. ResetMacroExpansionHelper helper(this); switch (Result.getKind()) { case tok::eod: return; // null directive. case tok::code_completion: if (CodeComplete) CodeComplete->CodeCompleteDirective( CurPPLexer->getConditionalStackDepth() > 0); setCodeCompletionReached(); return; case tok::numeric_constant: // # 7 GNU line marker directive. if (getLangOpts().AsmPreprocessor) break; // # 4 is not a preprocessor directive in .S files. return HandleDigitDirective(Result); default: IdentifierInfo *II = Result.getIdentifierInfo(); if (!II) break; // Not an identifier. // Ask what the preprocessor keyword ID is. switch (II->getPPKeywordID()) { default: break; // C99 6.10.1 - Conditional Inclusion. case tok::pp_if: return HandleIfDirective(Result, ReadAnyTokensBeforeDirective); case tok::pp_ifdef: return HandleIfdefDirective(Result, false, true/*not valid for miopt*/); case tok::pp_ifndef: return HandleIfdefDirective(Result, true, ReadAnyTokensBeforeDirective); case tok::pp_elif: return HandleElifDirective(Result); case tok::pp_else: return HandleElseDirective(Result); case tok::pp_endif: return HandleEndifDirective(Result); // C99 6.10.2 - Source File Inclusion. case tok::pp_include: // Handle #include. return HandleIncludeDirective(SavedHash.getLocation(), Result); case tok::pp___include_macros: // Handle -imacros. return HandleIncludeMacrosDirective(SavedHash.getLocation(), Result); // C99 6.10.3 - Macro Replacement. case tok::pp_define: return HandleDefineDirective(Result, ImmediatelyAfterTopLevelIfndef); case tok::pp_undef: return HandleUndefDirective(Result); // C99 6.10.4 - Line Control. case tok::pp_line: return HandleLineDirective(Result); // C99 6.10.5 - Error Directive. case tok::pp_error: return HandleUserDiagnosticDirective(Result, false); // C99 6.10.6 - Pragma Directive. case tok::pp_pragma: return HandlePragmaDirective(SavedHash.getLocation(), PIK_HashPragma); // GNU Extensions. case tok::pp_import: return HandleImportDirective(SavedHash.getLocation(), Result); case tok::pp_include_next: return HandleIncludeNextDirective(SavedHash.getLocation(), Result); case tok::pp_warning: Diag(Result, diag::ext_pp_warning_directive); return HandleUserDiagnosticDirective(Result, true); case tok::pp_ident: return HandleIdentSCCSDirective(Result); case tok::pp_sccs: return HandleIdentSCCSDirective(Result); case tok::pp_assert: //isExtension = true; // FIXME: implement #assert break; case tok::pp_unassert: //isExtension = true; // FIXME: implement #unassert break; case tok::pp___public_macro: if (getLangOpts().Modules) return HandleMacroPublicDirective(Result); break; case tok::pp___private_macro: if (getLangOpts().Modules) return HandleMacroPrivateDirective(Result); break; } break; } // If this is a .S file, treat unknown # directives as non-preprocessor // directives. This is important because # may be a comment or introduce // various pseudo-ops. Just return the # token and push back the following // token to be lexed next time. if (getLangOpts().AsmPreprocessor) { Token *Toks = new Token[2]; // Return the # and the token after it. Toks[0] = SavedHash; Toks[1] = Result; // If the second token is a hashhash token, then we need to translate it to // unknown so the token lexer doesn't try to perform token pasting. if (Result.is(tok::hashhash)) Toks[1].setKind(tok::unknown); // Enter this token stream so that we re-lex the tokens. Make sure to // enable macro expansion, in case the token after the # is an identifier // that is expanded. EnterTokenStream(Toks, 2, false, true); return; } // If we reached here, the preprocessing token is not valid! Diag(Result, diag::err_pp_invalid_directive); // Read the rest of the PP line. DiscardUntilEndOfDirective(); // Okay, we're done parsing the directive. } /// GetLineValue - Convert a numeric token into an unsigned value, emitting /// Diagnostic DiagID if it is invalid, and returning the value in Val. static bool GetLineValue(Token &DigitTok, unsigned &Val, unsigned DiagID, Preprocessor &PP, bool IsGNULineDirective=false) { if (DigitTok.isNot(tok::numeric_constant)) { PP.Diag(DigitTok, DiagID); if (DigitTok.isNot(tok::eod)) PP.DiscardUntilEndOfDirective(); return true; } SmallString<64> IntegerBuffer; IntegerBuffer.resize(DigitTok.getLength()); const char *DigitTokBegin = &IntegerBuffer[0]; bool Invalid = false; unsigned ActualLength = PP.getSpelling(DigitTok, DigitTokBegin, &Invalid); if (Invalid) return true; // Verify that we have a simple digit-sequence, and compute the value. This // is always a simple digit string computed in decimal, so we do this manually // here. Val = 0; for (unsigned i = 0; i != ActualLength; ++i) { // C++1y [lex.fcon]p1: // Optional separating single quotes in a digit-sequence are ignored if (DigitTokBegin[i] == '\'') continue; if (!isDigit(DigitTokBegin[i])) { PP.Diag(PP.AdvanceToTokenCharacter(DigitTok.getLocation(), i), diag::err_pp_line_digit_sequence) << IsGNULineDirective; PP.DiscardUntilEndOfDirective(); return true; } unsigned NextVal = Val*10+(DigitTokBegin[i]-'0'); if (NextVal < Val) { // overflow. PP.Diag(DigitTok, DiagID); PP.DiscardUntilEndOfDirective(); return true; } Val = NextVal; } if (DigitTokBegin[0] == '0' && Val) PP.Diag(DigitTok.getLocation(), diag::warn_pp_line_decimal) << IsGNULineDirective; return false; } /// \brief Handle a \#line directive: C99 6.10.4. /// /// The two acceptable forms are: /// \verbatim /// # line digit-sequence /// # line digit-sequence "s-char-sequence" /// \endverbatim void Preprocessor::HandleLineDirective(Token &Tok) { // Read the line # and string argument. Per C99 6.10.4p5, these tokens are // expanded. Token DigitTok; Lex(DigitTok); // Validate the number and convert it to an unsigned. unsigned LineNo; if (GetLineValue(DigitTok, LineNo, diag::err_pp_line_requires_integer,*this)) return; if (LineNo == 0) Diag(DigitTok, diag::ext_pp_line_zero); // Enforce C99 6.10.4p3: "The digit sequence shall not specify ... a // number greater than 2147483647". C90 requires that the line # be <= 32767. unsigned LineLimit = 32768U; if (LangOpts.C99 || LangOpts.CPlusPlus11) LineLimit = 2147483648U; if (LineNo >= LineLimit) Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit; else if (LangOpts.CPlusPlus11 && LineNo >= 32768U) Diag(DigitTok, diag::warn_cxx98_compat_pp_line_too_big); int FilenameID = -1; Token StrTok; Lex(StrTok); // If the StrTok is "eod", then it wasn't present. Otherwise, it must be a // string followed by eod. if (StrTok.is(tok::eod)) ; // ok else if (StrTok.isNot(tok::string_literal)) { Diag(StrTok, diag::err_pp_line_invalid_filename); return DiscardUntilEndOfDirective(); } else if (StrTok.hasUDSuffix()) { Diag(StrTok, diag::err_invalid_string_udl); return DiscardUntilEndOfDirective(); } else { // Parse and validate the string, converting it into a unique ID. StringLiteralParser Literal(&StrTok, 1, *this); assert(Literal.isAscii() && "Didn't allow wide strings in"); if (Literal.hadError) return DiscardUntilEndOfDirective(); if (Literal.Pascal) { Diag(StrTok, diag::err_pp_linemarker_invalid_filename); return DiscardUntilEndOfDirective(); } FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString()); // Verify that there is nothing after the string, other than EOD. Because // of C99 6.10.4p5, macros that expand to empty tokens are ok. CheckEndOfDirective("line", true); } SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID); if (Callbacks) Callbacks->FileChanged(CurPPLexer->getSourceLocation(), PPCallbacks::RenameFile, SrcMgr::C_User); } /// ReadLineMarkerFlags - Parse and validate any flags at the end of a GNU line /// marker directive. static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit, bool &IsSystemHeader, bool &IsExternCHeader, Preprocessor &PP) { unsigned FlagVal; Token FlagTok; PP.Lex(FlagTok); if (FlagTok.is(tok::eod)) return false; if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP)) return true; if (FlagVal == 1) { IsFileEntry = true; PP.Lex(FlagTok); if (FlagTok.is(tok::eod)) return false; if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP)) return true; } else if (FlagVal == 2) { IsFileExit = true; SourceManager &SM = PP.getSourceManager(); // If we are leaving the current presumed file, check to make sure the // presumed include stack isn't empty! FileID CurFileID = SM.getDecomposedExpansionLoc(FlagTok.getLocation()).first; PresumedLoc PLoc = SM.getPresumedLoc(FlagTok.getLocation()); if (PLoc.isInvalid()) return true; // If there is no include loc (main file) or if the include loc is in a // different physical file, then we aren't in a "1" line marker flag region. SourceLocation IncLoc = PLoc.getIncludeLoc(); if (IncLoc.isInvalid() || SM.getDecomposedExpansionLoc(IncLoc).first != CurFileID) { PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_pop); PP.DiscardUntilEndOfDirective(); return true; } PP.Lex(FlagTok); if (FlagTok.is(tok::eod)) return false; if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP)) return true; } // We must have 3 if there are still flags. if (FlagVal != 3) { PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); PP.DiscardUntilEndOfDirective(); return true; } IsSystemHeader = true; PP.Lex(FlagTok); if (FlagTok.is(tok::eod)) return false; if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP)) return true; // We must have 4 if there is yet another flag. if (FlagVal != 4) { PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); PP.DiscardUntilEndOfDirective(); return true; } IsExternCHeader = true; PP.Lex(FlagTok); if (FlagTok.is(tok::eod)) return false; // There are no more valid flags here. PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag); PP.DiscardUntilEndOfDirective(); return true; } /// HandleDigitDirective - Handle a GNU line marker directive, whose syntax is /// one of the following forms: /// /// # 42 /// # 42 "file" ('1' | '2')? /// # 42 "file" ('1' | '2')? '3' '4'? /// void Preprocessor::HandleDigitDirective(Token &DigitTok) { // Validate the number and convert it to an unsigned. GNU does not have a // line # limit other than it fit in 32-bits. unsigned LineNo; if (GetLineValue(DigitTok, LineNo, diag::err_pp_linemarker_requires_integer, *this, true)) return; Token StrTok; Lex(StrTok); bool IsFileEntry = false, IsFileExit = false; bool IsSystemHeader = false, IsExternCHeader = false; int FilenameID = -1; // If the StrTok is "eod", then it wasn't present. Otherwise, it must be a // string followed by eod. if (StrTok.is(tok::eod)) ; // ok else if (StrTok.isNot(tok::string_literal)) { Diag(StrTok, diag::err_pp_linemarker_invalid_filename); return DiscardUntilEndOfDirective(); } else if (StrTok.hasUDSuffix()) { Diag(StrTok, diag::err_invalid_string_udl); return DiscardUntilEndOfDirective(); } else { // Parse and validate the string, converting it into a unique ID. StringLiteralParser Literal(&StrTok, 1, *this); assert(Literal.isAscii() && "Didn't allow wide strings in"); if (Literal.hadError) return DiscardUntilEndOfDirective(); if (Literal.Pascal) { Diag(StrTok, diag::err_pp_linemarker_invalid_filename); return DiscardUntilEndOfDirective(); } FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString()); // If a filename was present, read any flags that are present. if (ReadLineMarkerFlags(IsFileEntry, IsFileExit, IsSystemHeader, IsExternCHeader, *this)) return; } // Create a line note with this information. SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID, IsFileEntry, IsFileExit, IsSystemHeader, IsExternCHeader); // If the preprocessor has callbacks installed, notify them of the #line // change. This is used so that the line marker comes out in -E mode for // example. if (Callbacks) { PPCallbacks::FileChangeReason Reason = PPCallbacks::RenameFile; if (IsFileEntry) Reason = PPCallbacks::EnterFile; else if (IsFileExit) Reason = PPCallbacks::ExitFile; SrcMgr::CharacteristicKind FileKind = SrcMgr::C_User; if (IsExternCHeader) FileKind = SrcMgr::C_ExternCSystem; else if (IsSystemHeader) FileKind = SrcMgr::C_System; Callbacks->FileChanged(CurPPLexer->getSourceLocation(), Reason, FileKind); } } /// HandleUserDiagnosticDirective - Handle a #warning or #error directive. /// void Preprocessor::HandleUserDiagnosticDirective(Token &Tok, bool isWarning) { // PTH doesn't emit #warning or #error directives. if (CurPTHLexer) return CurPTHLexer->DiscardToEndOfLine(); // Read the rest of the line raw. We do this because we don't want macros // to be expanded and we don't require that the tokens be valid preprocessing // tokens. For example, this is allowed: "#warning ` 'foo". GCC does // collapse multiple consequtive white space between tokens, but this isn't // specified by the standard. SmallString<128> Message; CurLexer->ReadToEndOfLine(&Message); // Find the first non-whitespace character, so that we can make the // diagnostic more succinct. StringRef Msg = Message.str().ltrim(" "); if (isWarning) Diag(Tok, diag::pp_hash_warning) << Msg; else Diag(Tok, diag::err_pp_hash_error) << Msg; } /// HandleIdentSCCSDirective - Handle a #ident/#sccs directive. /// void Preprocessor::HandleIdentSCCSDirective(Token &Tok) { // Yes, this directive is an extension. Diag(Tok, diag::ext_pp_ident_directive); // Read the string argument. Token StrTok; Lex(StrTok); // If the token kind isn't a string, it's a malformed directive. if (StrTok.isNot(tok::string_literal) && StrTok.isNot(tok::wide_string_literal)) { Diag(StrTok, diag::err_pp_malformed_ident); if (StrTok.isNot(tok::eod)) DiscardUntilEndOfDirective(); return; } if (StrTok.hasUDSuffix()) { Diag(StrTok, diag::err_invalid_string_udl); return DiscardUntilEndOfDirective(); } // Verify that there is nothing after the string, other than EOD. CheckEndOfDirective("ident"); if (Callbacks) { bool Invalid = false; std::string Str = getSpelling(StrTok, &Invalid); if (!Invalid) Callbacks->Ident(Tok.getLocation(), Str); } } /// \brief Handle a #public directive. void Preprocessor::HandleMacroPublicDirective(Token &Tok) { Token MacroNameTok; ReadMacroName(MacroNameTok, 2); // Error reading macro name? If so, diagnostic already issued. if (MacroNameTok.is(tok::eod)) return; // Check to see if this is the last token on the #__public_macro line. CheckEndOfDirective("__public_macro"); IdentifierInfo *II = MacroNameTok.getIdentifierInfo(); // Okay, we finally have a valid identifier to undef. MacroDirective *MD = getMacroDirective(II); // If the macro is not defined, this is an error. if (!MD) { Diag(MacroNameTok, diag::err_pp_visibility_non_macro) << II; return; } // Note that this macro has now been exported. appendMacroDirective(II, AllocateVisibilityMacroDirective( MacroNameTok.getLocation(), /*IsPublic=*/true)); } /// \brief Handle a #private directive. void Preprocessor::HandleMacroPrivateDirective(Token &Tok) { Token MacroNameTok; ReadMacroName(MacroNameTok, 2); // Error reading macro name? If so, diagnostic already issued. if (MacroNameTok.is(tok::eod)) return; // Check to see if this is the last token on the #__private_macro line. CheckEndOfDirective("__private_macro"); IdentifierInfo *II = MacroNameTok.getIdentifierInfo(); // Okay, we finally have a valid identifier to undef. MacroDirective *MD = getMacroDirective(II); // If the macro is not defined, this is an error. if (!MD) { Diag(MacroNameTok, diag::err_pp_visibility_non_macro) << II; return; } // Note that this macro has now been marked private. appendMacroDirective(II, AllocateVisibilityMacroDirective( MacroNameTok.getLocation(), /*IsPublic=*/false)); } //===----------------------------------------------------------------------===// // Preprocessor Include Directive Handling. //===----------------------------------------------------------------------===// /// GetIncludeFilenameSpelling - Turn the specified lexer token into a fully /// checked and spelled filename, e.g. as an operand of \#include. This returns /// true if the input filename was in <>'s or false if it were in ""'s. The /// caller is expected to provide a buffer that is large enough to hold the /// spelling of the filename, but is also expected to handle the case when /// this method decides to use a different buffer. bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc, StringRef &Buffer) { // Get the text form of the filename. assert(!Buffer.empty() && "Can't have tokens with empty spellings!"); // Make sure the filename is or "x". bool isAngled; if (Buffer[0] == '<') { if (Buffer.back() != '>') { Diag(Loc, diag::err_pp_expects_filename); Buffer = StringRef(); return true; } isAngled = true; } else if (Buffer[0] == '"') { if (Buffer.back() != '"') { Diag(Loc, diag::err_pp_expects_filename); Buffer = StringRef(); return true; } isAngled = false; } else { Diag(Loc, diag::err_pp_expects_filename); Buffer = StringRef(); return true; } // Diagnose #include "" as invalid. if (Buffer.size() <= 2) { Diag(Loc, diag::err_pp_empty_filename); Buffer = StringRef(); return true; } // Skip the brackets. Buffer = Buffer.substr(1, Buffer.size()-2); return isAngled; } // \brief Handle cases where the \#include name is expanded from a macro // as multiple tokens, which need to be glued together. // // This occurs for code like: // \code // \#define FOO // \#include FOO // \endcode // because in this case, "" is returned as 7 tokens, not one. // // This code concatenates and consumes tokens up to the '>' token. It returns // false if the > was found, otherwise it returns true if it finds and consumes // the EOD marker. bool Preprocessor::ConcatenateIncludeName(SmallString<128> &FilenameBuffer, SourceLocation &End) { Token CurTok; Lex(CurTok); while (CurTok.isNot(tok::eod)) { End = CurTok.getLocation(); // FIXME: Provide code completion for #includes. if (CurTok.is(tok::code_completion)) { setCodeCompletionReached(); Lex(CurTok); continue; } // Append the spelling of this token to the buffer. If there was a space // before it, add it now. if (CurTok.hasLeadingSpace()) FilenameBuffer.push_back(' '); // Get the spelling of the token, directly into FilenameBuffer if possible. unsigned PreAppendSize = FilenameBuffer.size(); FilenameBuffer.resize(PreAppendSize+CurTok.getLength()); const char *BufPtr = &FilenameBuffer[PreAppendSize]; unsigned ActualLen = getSpelling(CurTok, BufPtr); // If the token was spelled somewhere else, copy it into FilenameBuffer. if (BufPtr != &FilenameBuffer[PreAppendSize]) memcpy(&FilenameBuffer[PreAppendSize], BufPtr, ActualLen); // Resize FilenameBuffer to the correct size. if (CurTok.getLength() != ActualLen) FilenameBuffer.resize(PreAppendSize+ActualLen); // If we found the '>' marker, return success. if (CurTok.is(tok::greater)) return false; Lex(CurTok); } // If we hit the eod marker, emit an error and return true so that the caller // knows the EOD has been read. Diag(CurTok.getLocation(), diag::err_pp_expects_filename); return true; } /// \brief Push a token onto the token stream containing an annotation. static void EnterAnnotationToken(Preprocessor &PP, SourceLocation Begin, SourceLocation End, tok::TokenKind Kind, void *AnnotationVal) { Token *Tok = new Token[1]; Tok[0].startToken(); Tok[0].setKind(Kind); Tok[0].setLocation(Begin); Tok[0].setAnnotationEndLoc(End); Tok[0].setAnnotationValue(AnnotationVal); PP.EnterTokenStream(Tok, 1, true, true); } /// HandleIncludeDirective - The "\#include" tokens have just been read, read /// the file to be included from the lexer, then include it! This is a common /// routine with functionality shared between \#include, \#include_next and /// \#import. LookupFrom is set when this is a \#include_next directive, it /// specifies the file to start searching from. void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc, Token &IncludeTok, const DirectoryLookup *LookupFrom, bool isImport) { Token FilenameTok; CurPPLexer->LexIncludeFilename(FilenameTok); // Reserve a buffer to get the spelling. SmallString<128> FilenameBuffer; StringRef Filename; SourceLocation End; SourceLocation CharEnd; // the end of this directive, in characters switch (FilenameTok.getKind()) { case tok::eod: // If the token kind is EOD, the error has already been diagnosed. return; case tok::angle_string_literal: case tok::string_literal: Filename = getSpelling(FilenameTok, FilenameBuffer); End = FilenameTok.getLocation(); CharEnd = End.getLocWithOffset(FilenameTok.getLength()); break; case tok::less: // This could be a file coming from a macro expansion. In this // case, glue the tokens together into FilenameBuffer and interpret those. FilenameBuffer.push_back('<'); if (ConcatenateIncludeName(FilenameBuffer, End)) return; // Found but no ">"? Diagnostic already emitted. Filename = FilenameBuffer.str(); CharEnd = End.getLocWithOffset(1); break; default: Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename); DiscardUntilEndOfDirective(); return; } CharSourceRange FilenameRange = CharSourceRange::getCharRange(FilenameTok.getLocation(), CharEnd); StringRef OriginalFilename = Filename; bool isAngled = GetIncludeFilenameSpelling(FilenameTok.getLocation(), Filename); // If GetIncludeFilenameSpelling set the start ptr to null, there was an // error. if (Filename.empty()) { DiscardUntilEndOfDirective(); return; } // Verify that there is nothing after the filename, other than EOD. Note that // we allow macros that expand to nothing after the filename, because this // falls into the category of "#include pp-tokens new-line" specified in // C99 6.10.2p4. CheckEndOfDirective(IncludeTok.getIdentifierInfo()->getNameStart(), true); // Check that we don't have infinite #include recursion. if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1) { Diag(FilenameTok, diag::err_pp_include_too_deep); return; } // Complain about attempts to #include files in an audit pragma. if (PragmaARCCFCodeAuditedLoc.isValid()) { Diag(HashLoc, diag::err_pp_include_in_arc_cf_code_audited); Diag(PragmaARCCFCodeAuditedLoc, diag::note_pragma_entered_here); // Immediately leave the pragma. PragmaARCCFCodeAuditedLoc = SourceLocation(); } if (HeaderInfo.HasIncludeAliasMap()) { // Map the filename with the brackets still attached. If the name doesn't // map to anything, fall back on the filename we've already gotten the // spelling for. StringRef NewName = HeaderInfo.MapHeaderToIncludeAlias(OriginalFilename); if (!NewName.empty()) Filename = NewName; } // Search include directories. const DirectoryLookup *CurDir; SmallString<1024> SearchPath; SmallString<1024> RelativePath; // We get the raw path only if we have 'Callbacks' to which we later pass // the path. ModuleMap::KnownHeader SuggestedModule; SourceLocation FilenameLoc = FilenameTok.getLocation(); SmallString<128> NormalizedPath; if (LangOpts.MSVCCompat) { NormalizedPath = Filename.str(); llvm::sys::fs::normalize_separators(NormalizedPath); } const FileEntry *File = LookupFile( FilenameLoc, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled, LookupFrom, CurDir, Callbacks ? &SearchPath : nullptr, Callbacks ? &RelativePath : nullptr, HeaderInfo.getHeaderSearchOpts().ModuleMaps ? &SuggestedModule : nullptr); if (Callbacks) { if (!File) { // Give the clients a chance to recover. SmallString<128> RecoveryPath; if (Callbacks->FileNotFound(Filename, RecoveryPath)) { if (const DirectoryEntry *DE = FileMgr.getDirectory(RecoveryPath)) { // Add the recovery path to the list of search paths. DirectoryLookup DL(DE, SrcMgr::C_User, false); HeaderInfo.AddSearchPath(DL, isAngled); // Try the lookup again, skipping the cache. File = LookupFile(FilenameLoc, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled, LookupFrom, CurDir, nullptr, nullptr, HeaderInfo.getHeaderSearchOpts().ModuleMaps ? &SuggestedModule : nullptr, /*SkipCache*/ true); } } } if (!SuggestedModule || !getLangOpts().Modules) { // Notify the callback object that we've seen an inclusion directive. Callbacks->InclusionDirective(HashLoc, IncludeTok, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled, FilenameRange, File, SearchPath, RelativePath, /*ImportedModule=*/nullptr); } } if (!File) { if (!SuppressIncludeNotFoundError) { // If the file could not be located and it was included via angle // brackets, we can attempt a lookup as though it were a quoted path to // provide the user with a possible fixit. if (isAngled) { File = LookupFile( FilenameLoc, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, false, LookupFrom, CurDir, Callbacks ? &SearchPath : nullptr, Callbacks ? &RelativePath : nullptr, HeaderInfo.getHeaderSearchOpts().ModuleMaps ? &SuggestedModule : nullptr); if (File) { SourceRange Range(FilenameTok.getLocation(), CharEnd); Diag(FilenameTok, diag::err_pp_file_not_found_not_fatal) << Filename << FixItHint::CreateReplacement(Range, "\"" + Filename.str() + "\""); } } // If the file is still not found, just go with the vanilla diagnostic if (!File) Diag(FilenameTok, diag::err_pp_file_not_found) << Filename; } if (!File) return; } // If we are supposed to import a module rather than including the header, // do so now. if (SuggestedModule && getLangOpts().Modules) { // Compute the module access path corresponding to this module. // FIXME: Should we have a second loadModule() overload to avoid this // extra lookup step? SmallVector, 2> Path; for (Module *Mod = SuggestedModule.getModule(); Mod; Mod = Mod->Parent) Path.push_back(std::make_pair(getIdentifierInfo(Mod->Name), FilenameTok.getLocation())); std::reverse(Path.begin(), Path.end()); // Warn that we're replacing the include/import with a module import. SmallString<128> PathString; for (unsigned I = 0, N = Path.size(); I != N; ++I) { if (I) PathString += '.'; PathString += Path[I].first->getName(); } int IncludeKind = 0; switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) { case tok::pp_include: IncludeKind = 0; break; case tok::pp_import: IncludeKind = 1; break; case tok::pp_include_next: IncludeKind = 2; break; case tok::pp___include_macros: IncludeKind = 3; break; default: llvm_unreachable("unknown include directive kind"); } // Determine whether we are actually building the module that this // include directive maps to. bool BuildingImportedModule = Path[0].first->getName() == getLangOpts().CurrentModule; if (!BuildingImportedModule && getLangOpts().ObjC2) { // If we're not building the imported module, warn that we're going // to automatically turn this inclusion directive into a module import. // We only do this in Objective-C, where we have a module-import syntax. CharSourceRange ReplaceRange(SourceRange(HashLoc, CharEnd), /*IsTokenRange=*/false); Diag(HashLoc, diag::warn_auto_module_import) << IncludeKind << PathString << FixItHint::CreateReplacement(ReplaceRange, "@import " + PathString.str().str() + ";"); } // Load the module. Only make macros visible. We'll make the declarations // visible when the parser gets here. Module::NameVisibilityKind Visibility = Module::MacrosVisible; ModuleLoadResult Imported = TheModuleLoader.loadModule(IncludeTok.getLocation(), Path, Visibility, /*IsIncludeDirective=*/true); assert((Imported == nullptr || Imported == SuggestedModule.getModule()) && "the imported module is different than the suggested one"); if (!Imported && hadModuleLoaderFatalFailure()) { // With a fatal failure in the module loader, we abort parsing. Token &Result = IncludeTok; if (CurLexer) { Result.startToken(); CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd, tok::eof); CurLexer->cutOffLexing(); } else { assert(CurPTHLexer && "#include but no current lexer set!"); CurPTHLexer->getEOF(Result); } return; } // If this header isn't part of the module we're building, we're done. if (!BuildingImportedModule && Imported) { if (Callbacks) { Callbacks->InclusionDirective(HashLoc, IncludeTok, Filename, isAngled, FilenameRange, File, SearchPath, RelativePath, Imported); } if (IncludeKind != 3) { // Let the parser know that we hit a module import, and it should // make the module visible. // FIXME: Produce this as the current token directly, rather than // allocating a new token for it. EnterAnnotationToken(*this, HashLoc, End, tok::annot_module_include, Imported); } return; } // If we failed to find a submodule that we expected to find, we can // continue. Otherwise, there's an error in the included file, so we // don't want to include it. if (!BuildingImportedModule && !Imported.isMissingExpected()) { return; } } if (Callbacks && SuggestedModule) { // We didn't notify the callback object that we've seen an inclusion // directive before. Now that we are parsing the include normally and not // turning it to a module import, notify the callback object. Callbacks->InclusionDirective(HashLoc, IncludeTok, Filename, isAngled, FilenameRange, File, SearchPath, RelativePath, /*ImportedModule=*/nullptr); } // The #included file will be considered to be a system header if either it is // in a system include directory, or if the #includer is a system include // header. SrcMgr::CharacteristicKind FileCharacter = std::max(HeaderInfo.getFileDirFlavor(File), SourceMgr.getFileCharacteristic(FilenameTok.getLocation())); // Ask HeaderInfo if we should enter this #include file. If not, #including // this file will have no effect. if (!HeaderInfo.ShouldEnterIncludeFile(File, isImport)) { if (Callbacks) Callbacks->FileSkipped(*File, FilenameTok, FileCharacter); return; } // Look up the file, create a File ID for it. SourceLocation IncludePos = End; // If the filename string was the result of macro expansions, set the include // position on the file where it will be included and after the expansions. if (IncludePos.isMacroID()) IncludePos = SourceMgr.getExpansionRange(IncludePos).second; FileID FID = SourceMgr.createFileID(File, IncludePos, FileCharacter); assert(!FID.isInvalid() && "Expected valid file ID"); // Determine if we're switching to building a new submodule, and which one. ModuleMap::KnownHeader BuildingModule; if (getLangOpts().Modules && !getLangOpts().CurrentModule.empty()) { Module *RequestingModule = getModuleForLocation(FilenameLoc); BuildingModule = HeaderInfo.getModuleMap().findModuleForHeader(File, RequestingModule); } // If all is good, enter the new file! if (EnterSourceFile(FID, CurDir, FilenameTok.getLocation())) return; // If we're walking into another part of the same module, let the parser // know that any future declarations are within that other submodule. if (BuildingModule) { assert(!CurSubmodule && "should not have marked this as a module yet"); CurSubmodule = BuildingModule.getModule(); EnterAnnotationToken(*this, HashLoc, End, tok::annot_module_begin, CurSubmodule); } } /// HandleIncludeNextDirective - Implements \#include_next. /// void Preprocessor::HandleIncludeNextDirective(SourceLocation HashLoc, Token &IncludeNextTok) { Diag(IncludeNextTok, diag::ext_pp_include_next_directive); // #include_next is like #include, except that we start searching after // the current found directory. If we can't do this, issue a // diagnostic. const DirectoryLookup *Lookup = CurDirLookup; if (isInPrimaryFile()) { Lookup = nullptr; Diag(IncludeNextTok, diag::pp_include_next_in_primary); } else if (!Lookup) { Diag(IncludeNextTok, diag::pp_include_next_absolute_path); } else { // Start looking up in the next directory. ++Lookup; } return HandleIncludeDirective(HashLoc, IncludeNextTok, Lookup); } /// HandleMicrosoftImportDirective - Implements \#import for Microsoft Mode void Preprocessor::HandleMicrosoftImportDirective(Token &Tok) { // The Microsoft #import directive takes a type library and generates header // files from it, and includes those. This is beyond the scope of what clang // does, so we ignore it and error out. However, #import can optionally have // trailing attributes that span multiple lines. We're going to eat those // so we can continue processing from there. Diag(Tok, diag::err_pp_import_directive_ms ); // Read tokens until we get to the end of the directive. Note that the // directive can be split over multiple lines using the backslash character. DiscardUntilEndOfDirective(); } /// HandleImportDirective - Implements \#import. /// void Preprocessor::HandleImportDirective(SourceLocation HashLoc, Token &ImportTok) { if (!LangOpts.ObjC1) { // #import is standard for ObjC. if (LangOpts.MSVCCompat) return HandleMicrosoftImportDirective(ImportTok); Diag(ImportTok, diag::ext_pp_import_directive); } return HandleIncludeDirective(HashLoc, ImportTok, nullptr, true); } /// HandleIncludeMacrosDirective - The -imacros command line option turns into a /// pseudo directive in the predefines buffer. This handles it by sucking all /// tokens through the preprocessor and discarding them (only keeping the side /// effects on the preprocessor). void Preprocessor::HandleIncludeMacrosDirective(SourceLocation HashLoc, Token &IncludeMacrosTok) { // This directive should only occur in the predefines buffer. If not, emit an // error and reject it. SourceLocation Loc = IncludeMacrosTok.getLocation(); if (strcmp(SourceMgr.getBufferName(Loc), "") != 0) { Diag(IncludeMacrosTok.getLocation(), diag::pp_include_macros_out_of_predefines); DiscardUntilEndOfDirective(); return; } // Treat this as a normal #include for checking purposes. If this is // successful, it will push a new lexer onto the include stack. HandleIncludeDirective(HashLoc, IncludeMacrosTok, nullptr, false); Token TmpTok; do { Lex(TmpTok); assert(TmpTok.isNot(tok::eof) && "Didn't find end of -imacros!"); } while (TmpTok.isNot(tok::hashhash)); } //===----------------------------------------------------------------------===// // Preprocessor Macro Directive Handling. //===----------------------------------------------------------------------===// /// ReadMacroDefinitionArgList - The ( starting an argument list of a macro /// definition has just been read. Lex the rest of the arguments and the /// closing ), updating MI with what we learn. Return true if an error occurs /// parsing the arg list. bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI, Token &Tok) { SmallVector Arguments; while (1) { LexUnexpandedToken(Tok); switch (Tok.getKind()) { case tok::r_paren: // Found the end of the argument list. if (Arguments.empty()) // #define FOO() return false; // Otherwise we have #define FOO(A,) Diag(Tok, diag::err_pp_expected_ident_in_arg_list); return true; case tok::ellipsis: // #define X(... -> C99 varargs if (!LangOpts.C99) Diag(Tok, LangOpts.CPlusPlus11 ? diag::warn_cxx98_compat_variadic_macro : diag::ext_variadic_macro); // OpenCL v1.2 s6.9.e: variadic macros are not supported. if (LangOpts.OpenCL) { Diag(Tok, diag::err_pp_opencl_variadic_macros); return true; } // Lex the token after the identifier. LexUnexpandedToken(Tok); if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); return true; } // Add the __VA_ARGS__ identifier as an argument. Arguments.push_back(Ident__VA_ARGS__); MI->setIsC99Varargs(); MI->setArgumentList(&Arguments[0], Arguments.size(), BP); return false; case tok::eod: // #define X( Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); return true; default: // Handle keywords and identifiers here to accept things like // #define Foo(for) for. IdentifierInfo *II = Tok.getIdentifierInfo(); if (!II) { // #define X(1 Diag(Tok, diag::err_pp_invalid_tok_in_arg_list); return true; } // If this is already used as an argument, it is used multiple times (e.g. // #define X(A,A. if (std::find(Arguments.begin(), Arguments.end(), II) != Arguments.end()) { // C99 6.10.3p6 Diag(Tok, diag::err_pp_duplicate_name_in_arg_list) << II; return true; } // Add the argument to the macro info. Arguments.push_back(II); // Lex the token after the identifier. LexUnexpandedToken(Tok); switch (Tok.getKind()) { default: // #define X(A B Diag(Tok, diag::err_pp_expected_comma_in_arg_list); return true; case tok::r_paren: // #define X(A) MI->setArgumentList(&Arguments[0], Arguments.size(), BP); return false; case tok::comma: // #define X(A, break; case tok::ellipsis: // #define X(A... -> GCC extension // Diagnose extension. Diag(Tok, diag::ext_named_variadic_macro); // Lex the token after the identifier. LexUnexpandedToken(Tok); if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_pp_missing_rparen_in_macro_def); return true; } MI->setIsGNUVarargs(); MI->setArgumentList(&Arguments[0], Arguments.size(), BP); return false; } } } } /// HandleDefineDirective - Implements \#define. This consumes the entire macro /// line then lets the caller lex the next real token. void Preprocessor::HandleDefineDirective(Token &DefineTok, bool ImmediatelyAfterHeaderGuard) { ++NumDefined; Token MacroNameTok; ReadMacroName(MacroNameTok, 1); // Error reading macro name? If so, diagnostic already issued. if (MacroNameTok.is(tok::eod)) return; Token LastTok = MacroNameTok; // If we are supposed to keep comments in #defines, reenable comment saving // mode. if (CurLexer) CurLexer->SetCommentRetentionState(KeepMacroComments); // Create the new macro. MacroInfo *MI = AllocateMacroInfo(MacroNameTok.getLocation()); Token Tok; LexUnexpandedToken(Tok); // If this is a function-like macro definition, parse the argument list, // marking each of the identifiers as being used as macro arguments. Also, // check other constraints on the first token of the macro body. if (Tok.is(tok::eod)) { if (ImmediatelyAfterHeaderGuard) { // Save this macro information since it may part of a header guard. CurPPLexer->MIOpt.SetDefinedMacro(MacroNameTok.getIdentifierInfo(), MacroNameTok.getLocation()); } // If there is no body to this macro, we have no special handling here. } else if (Tok.hasLeadingSpace()) { // This is a normal token with leading space. Clear the leading space // marker on the first token to get proper expansion. Tok.clearFlag(Token::LeadingSpace); } else if (Tok.is(tok::l_paren)) { // This is a function-like macro definition. Read the argument list. MI->setIsFunctionLike(); if (ReadMacroDefinitionArgList(MI, LastTok)) { // Forget about MI. ReleaseMacroInfo(MI); // Throw away the rest of the line. if (CurPPLexer->ParsingPreprocessorDirective) DiscardUntilEndOfDirective(); return; } // If this is a definition of a variadic C99 function-like macro, not using // the GNU named varargs extension, enabled __VA_ARGS__. // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro. // This gets unpoisoned where it is allowed. assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned!"); if (MI->isC99Varargs()) Ident__VA_ARGS__->setIsPoisoned(false); // Read the first token after the arg list for down below. LexUnexpandedToken(Tok); } else if (LangOpts.C99 || LangOpts.CPlusPlus11) { // C99 requires whitespace between the macro definition and the body. Emit // a diagnostic for something like "#define X+". Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name); } else { // C90 6.8 TC1 says: "In the definition of an object-like macro, if the // first character of a replacement list is not a character required by // subclause 5.2.1, then there shall be white-space separation between the // identifier and the replacement list.". 5.2.1 lists this set: // "A-Za-z0-9!"#%&'()*+,_./:;<=>?[\]^_{|}~" as well as whitespace, which // is irrelevant here. bool isInvalid = false; if (Tok.is(tok::at)) // @ is not in the list above. isInvalid = true; else if (Tok.is(tok::unknown)) { // If we have an unknown token, it is something strange like "`". Since // all of valid characters would have lexed into a single character // token of some sort, we know this is not a valid case. isInvalid = true; } if (isInvalid) Diag(Tok, diag::ext_missing_whitespace_after_macro_name); else Diag(Tok, diag::warn_missing_whitespace_after_macro_name); } if (!Tok.is(tok::eod)) LastTok = Tok; // Read the rest of the macro body. if (MI->isObjectLike()) { // Object-like macros are very simple, just read their body. while (Tok.isNot(tok::eod)) { LastTok = Tok; MI->AddTokenToBody(Tok); // Get the next token of the macro. LexUnexpandedToken(Tok); } } else { // Otherwise, read the body of a function-like macro. While we are at it, // check C99 6.10.3.2p1: ensure that # operators are followed by macro // parameters in function-like macro expansions. while (Tok.isNot(tok::eod)) { LastTok = Tok; if (Tok.isNot(tok::hash) && Tok.isNot(tok::hashhash)) { MI->AddTokenToBody(Tok); // Get the next token of the macro. LexUnexpandedToken(Tok); continue; } // If we're in -traditional mode, then we should ignore stringification // and token pasting. Mark the tokens as unknown so as not to confuse // things. if (getLangOpts().TraditionalCPP) { Tok.setKind(tok::unknown); MI->AddTokenToBody(Tok); // Get the next token of the macro. LexUnexpandedToken(Tok); continue; } if (Tok.is(tok::hashhash)) { // If we see token pasting, check if it looks like the gcc comma // pasting extension. We'll use this information to suppress // diagnostics later on. // Get the next token of the macro. LexUnexpandedToken(Tok); if (Tok.is(tok::eod)) { MI->AddTokenToBody(LastTok); break; } unsigned NumTokens = MI->getNumTokens(); if (NumTokens && Tok.getIdentifierInfo() == Ident__VA_ARGS__ && MI->getReplacementToken(NumTokens-1).is(tok::comma)) MI->setHasCommaPasting(); // Things look ok, add the '##' token to the macro. MI->AddTokenToBody(LastTok); continue; } // Get the next token of the macro. LexUnexpandedToken(Tok); // Check for a valid macro arg identifier. if (Tok.getIdentifierInfo() == nullptr || MI->getArgumentNum(Tok.getIdentifierInfo()) == -1) { // If this is assembler-with-cpp mode, we accept random gibberish after // the '#' because '#' is often a comment character. However, change // the kind of the token to tok::unknown so that the preprocessor isn't // confused. if (getLangOpts().AsmPreprocessor && Tok.isNot(tok::eod)) { LastTok.setKind(tok::unknown); MI->AddTokenToBody(LastTok); continue; } else { Diag(Tok, diag::err_pp_stringize_not_parameter); ReleaseMacroInfo(MI); // Disable __VA_ARGS__ again. Ident__VA_ARGS__->setIsPoisoned(true); return; } } // Things look ok, add the '#' and param name tokens to the macro. MI->AddTokenToBody(LastTok); MI->AddTokenToBody(Tok); LastTok = Tok; // Get the next token of the macro. LexUnexpandedToken(Tok); } } // Disable __VA_ARGS__ again. Ident__VA_ARGS__->setIsPoisoned(true); // Check that there is no paste (##) operator at the beginning or end of the // replacement list. unsigned NumTokens = MI->getNumTokens(); if (NumTokens != 0) { if (MI->getReplacementToken(0).is(tok::hashhash)) { Diag(MI->getReplacementToken(0), diag::err_paste_at_start); ReleaseMacroInfo(MI); return; } if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) { Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end); ReleaseMacroInfo(MI); return; } } MI->setDefinitionEndLoc(LastTok.getLocation()); // Finally, if this identifier already had a macro defined for it, verify that // the macro bodies are identical, and issue diagnostics if they are not. if (const MacroInfo *OtherMI=getMacroInfo(MacroNameTok.getIdentifierInfo())) { // It is very common for system headers to have tons of macro redefinitions // and for warnings to be disabled in system headers. If this is the case, // then don't bother calling MacroInfo::isIdenticalTo. if (!getDiagnostics().getSuppressSystemWarnings() || !SourceMgr.isInSystemHeader(DefineTok.getLocation())) { if (!OtherMI->isUsed() && OtherMI->isWarnIfUnused()) Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used); // Warn if defining "__LINE__" and other builtins, per C99 6.10.8/4 and // C++ [cpp.predefined]p4, but allow it as an extension. if (OtherMI->isBuiltinMacro()) Diag(MacroNameTok, diag::ext_pp_redef_builtin_macro); // Macros must be identical. This means all tokens and whitespace // separation must be the same. C99 6.10.3p2. else if (!OtherMI->isAllowRedefinitionsWithoutWarning() && !MI->isIdenticalTo(*OtherMI, *this, /*Syntactic=*/LangOpts.MicrosoftExt)) { Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef) << MacroNameTok.getIdentifierInfo(); Diag(OtherMI->getDefinitionLoc(), diag::note_previous_definition); } } if (OtherMI->isWarnIfUnused()) WarnUnusedMacroLocs.erase(OtherMI->getDefinitionLoc()); } DefMacroDirective *MD = appendDefMacroDirective(MacroNameTok.getIdentifierInfo(), MI); assert(!MI->isUsed()); // If we need warning for not using the macro, add its location in the // warn-because-unused-macro set. If it gets used it will be removed from set. if (getSourceManager().isInMainFile(MI->getDefinitionLoc()) && !Diags->isIgnored(diag::pp_macro_not_used, MI->getDefinitionLoc())) { MI->setIsWarnIfUnused(true); WarnUnusedMacroLocs.insert(MI->getDefinitionLoc()); } // If the callbacks want to know, tell them about the macro definition. if (Callbacks) Callbacks->MacroDefined(MacroNameTok, MD); } /// HandleUndefDirective - Implements \#undef. /// void Preprocessor::HandleUndefDirective(Token &UndefTok) { ++NumUndefined; Token MacroNameTok; ReadMacroName(MacroNameTok, 2); // Error reading macro name? If so, diagnostic already issued. if (MacroNameTok.is(tok::eod)) return; // Check to see if this is the last token on the #undef line. CheckEndOfDirective("undef"); // Okay, we finally have a valid identifier to undef. MacroDirective *MD = getMacroDirective(MacroNameTok.getIdentifierInfo()); const MacroInfo *MI = MD ? MD->getMacroInfo() : nullptr; // If the callbacks want to know, tell them about the macro #undef. // Note: no matter if the macro was defined or not. if (Callbacks) Callbacks->MacroUndefined(MacroNameTok, MD); // If the macro is not defined, this is a noop undef, just return. if (!MI) return; if (!MI->isUsed() && MI->isWarnIfUnused()) Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used); if (MI->isWarnIfUnused()) WarnUnusedMacroLocs.erase(MI->getDefinitionLoc()); appendMacroDirective(MacroNameTok.getIdentifierInfo(), AllocateUndefMacroDirective(MacroNameTok.getLocation())); } //===----------------------------------------------------------------------===// // Preprocessor Conditional Directive Handling. //===----------------------------------------------------------------------===// /// HandleIfdefDirective - Implements the \#ifdef/\#ifndef directive. isIfndef /// is true when this is a \#ifndef directive. ReadAnyTokensBeforeDirective is /// true if any tokens have been returned or pp-directives activated before this /// \#ifndef has been lexed. /// void Preprocessor::HandleIfdefDirective(Token &Result, bool isIfndef, bool ReadAnyTokensBeforeDirective) { ++NumIf; Token DirectiveTok = Result; Token MacroNameTok; ReadMacroName(MacroNameTok); // Error reading macro name? If so, diagnostic already issued. if (MacroNameTok.is(tok::eod)) { // Skip code until we get to #endif. This helps with recovery by not // emitting an error when the #endif is reached. SkipExcludedConditionalBlock(DirectiveTok.getLocation(), /*Foundnonskip*/false, /*FoundElse*/false); return; } // Check to see if this is the last token on the #if[n]def line. CheckEndOfDirective(isIfndef ? "ifndef" : "ifdef"); IdentifierInfo *MII = MacroNameTok.getIdentifierInfo(); MacroDirective *MD = getMacroDirective(MII); MacroInfo *MI = MD ? MD->getMacroInfo() : nullptr; if (CurPPLexer->getConditionalStackDepth() == 0) { // If the start of a top-level #ifdef and if the macro is not defined, // inform MIOpt that this might be the start of a proper include guard. // Otherwise it is some other form of unknown conditional which we can't // handle. if (!ReadAnyTokensBeforeDirective && !MI) { assert(isIfndef && "#ifdef shouldn't reach here"); CurPPLexer->MIOpt.EnterTopLevelIfndef(MII, MacroNameTok.getLocation()); } else CurPPLexer->MIOpt.EnterTopLevelConditional(); } // If there is a macro, process it. if (MI) // Mark it used. markMacroAsUsed(MI); if (Callbacks) { if (isIfndef) Callbacks->Ifndef(DirectiveTok.getLocation(), MacroNameTok, MD); else Callbacks->Ifdef(DirectiveTok.getLocation(), MacroNameTok, MD); } // Should we include the stuff contained by this directive? if (!MI == isIfndef) { // Yes, remember that we are inside a conditional, then lex the next token. CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(), /*wasskip*/false, /*foundnonskip*/true, /*foundelse*/false); } else { // No, skip the contents of this block. SkipExcludedConditionalBlock(DirectiveTok.getLocation(), /*Foundnonskip*/false, /*FoundElse*/false); } } /// HandleIfDirective - Implements the \#if directive. /// void Preprocessor::HandleIfDirective(Token &IfToken, bool ReadAnyTokensBeforeDirective) { ++NumIf; // Parse and evaluate the conditional expression. IdentifierInfo *IfNDefMacro = nullptr; const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation(); const bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro); const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation(); // If this condition is equivalent to #ifndef X, and if this is the first // directive seen, handle it for the multiple-include optimization. if (CurPPLexer->getConditionalStackDepth() == 0) { if (!ReadAnyTokensBeforeDirective && IfNDefMacro && ConditionalTrue) // FIXME: Pass in the location of the macro name, not the 'if' token. CurPPLexer->MIOpt.EnterTopLevelIfndef(IfNDefMacro, IfToken.getLocation()); else CurPPLexer->MIOpt.EnterTopLevelConditional(); } if (Callbacks) Callbacks->If(IfToken.getLocation(), SourceRange(ConditionalBegin, ConditionalEnd), (ConditionalTrue ? PPCallbacks::CVK_True : PPCallbacks::CVK_False)); // Should we include the stuff contained by this directive? if (ConditionalTrue) { // Yes, remember that we are inside a conditional, then lex the next token. CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false, /*foundnonskip*/true, /*foundelse*/false); } else { // No, skip the contents of this block. SkipExcludedConditionalBlock(IfToken.getLocation(), /*Foundnonskip*/false, /*FoundElse*/false); } } /// HandleEndifDirective - Implements the \#endif directive. /// void Preprocessor::HandleEndifDirective(Token &EndifToken) { ++NumEndif; // Check that this is the whole directive. CheckEndOfDirective("endif"); PPConditionalInfo CondInfo; if (CurPPLexer->popConditionalLevel(CondInfo)) { // No conditionals on the stack: this is an #endif without an #if. Diag(EndifToken, diag::err_pp_endif_without_if); return; } // If this the end of a top-level #endif, inform MIOpt. if (CurPPLexer->getConditionalStackDepth() == 0) CurPPLexer->MIOpt.ExitTopLevelConditional(); assert(!CondInfo.WasSkipping && !CurPPLexer->LexingRawMode && "This code should only be reachable in the non-skipping case!"); if (Callbacks) Callbacks->Endif(EndifToken.getLocation(), CondInfo.IfLoc); } /// HandleElseDirective - Implements the \#else directive. /// void Preprocessor::HandleElseDirective(Token &Result) { ++NumElse; // #else directive in a non-skipping conditional... start skipping. CheckEndOfDirective("else"); PPConditionalInfo CI; if (CurPPLexer->popConditionalLevel(CI)) { Diag(Result, diag::pp_err_else_without_if); return; } // If this is a top-level #else, inform the MIOpt. if (CurPPLexer->getConditionalStackDepth() == 0) CurPPLexer->MIOpt.EnterTopLevelConditional(); // If this is a #else with a #else before it, report the error. if (CI.FoundElse) Diag(Result, diag::pp_err_else_after_else); if (Callbacks) Callbacks->Else(Result.getLocation(), CI.IfLoc); // Finally, skip the rest of the contents of this block. SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, /*FoundElse*/true, Result.getLocation()); } /// HandleElifDirective - Implements the \#elif directive. /// void Preprocessor::HandleElifDirective(Token &ElifToken) { ++NumElse; // #elif directive in a non-skipping conditional... start skipping. // We don't care what the condition is, because we will always skip it (since // the block immediately before it was included). const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation(); DiscardUntilEndOfDirective(); const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation(); PPConditionalInfo CI; if (CurPPLexer->popConditionalLevel(CI)) { Diag(ElifToken, diag::pp_err_elif_without_if); return; } // If this is a top-level #elif, inform the MIOpt. if (CurPPLexer->getConditionalStackDepth() == 0) CurPPLexer->MIOpt.EnterTopLevelConditional(); // If this is a #elif with a #else before it, report the error. if (CI.FoundElse) Diag(ElifToken, diag::pp_err_elif_after_else); if (Callbacks) Callbacks->Elif(ElifToken.getLocation(), SourceRange(ConditionalBegin, ConditionalEnd), PPCallbacks::CVK_NotEvaluated, CI.IfLoc); // Finally, skip the rest of the contents of this block. SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, /*FoundElse*/CI.FoundElse, ElifToken.getLocation()); }