//===- Pragma.cpp - Pragma registration and handling ----------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This file implements the PragmaHandler/PragmaTable interfaces and implements // pragma related methods of the Preprocessor class. // //===----------------------------------------------------------------------===// #include "clang/Lex/Pragma.h" #include "clang/Basic/Diagnostic.h" #include "clang/Basic/FileManager.h" #include "clang/Basic/IdentifierTable.h" #include "clang/Basic/LLVM.h" #include "clang/Basic/LangOptions.h" #include "clang/Basic/Module.h" #include "clang/Basic/SourceLocation.h" #include "clang/Basic/SourceManager.h" #include "clang/Basic/TokenKinds.h" #include "clang/Lex/HeaderSearch.h" #include "clang/Lex/LexDiagnostic.h" #include "clang/Lex/Lexer.h" #include "clang/Lex/LiteralSupport.h" #include "clang/Lex/MacroInfo.h" #include "clang/Lex/ModuleLoader.h" #include "clang/Lex/PPCallbacks.h" #include "clang/Lex/Preprocessor.h" #include "clang/Lex/PreprocessorLexer.h" #include "clang/Lex/PreprocessorOptions.h" #include "clang/Lex/Token.h" #include "clang/Lex/TokenLexer.h" #include "llvm/ADT/ArrayRef.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallString.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/StringSwitch.h" #include "llvm/ADT/StringRef.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/Timer.h" #include #include #include #include #include #include #include #include using namespace clang; // Out-of-line destructor to provide a home for the class. PragmaHandler::~PragmaHandler() = default; //===----------------------------------------------------------------------===// // EmptyPragmaHandler Implementation. //===----------------------------------------------------------------------===// EmptyPragmaHandler::EmptyPragmaHandler(StringRef Name) : PragmaHandler(Name) {} void EmptyPragmaHandler::HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &FirstToken) {} //===----------------------------------------------------------------------===// // PragmaNamespace Implementation. //===----------------------------------------------------------------------===// /// FindHandler - Check to see if there is already a handler for the /// specified name. If not, return the handler for the null identifier if it /// exists, otherwise return null. If IgnoreNull is true (the default) then /// the null handler isn't returned on failure to match. PragmaHandler *PragmaNamespace::FindHandler(StringRef Name, bool IgnoreNull) const { auto I = Handlers.find(Name); if (I != Handlers.end()) return I->getValue().get(); if (IgnoreNull) return nullptr; I = Handlers.find(StringRef()); if (I != Handlers.end()) return I->getValue().get(); return nullptr; } void PragmaNamespace::AddPragma(PragmaHandler *Handler) { assert(!Handlers.count(Handler->getName()) && "A handler with this name is already registered in this namespace"); Handlers[Handler->getName()].reset(Handler); } void PragmaNamespace::RemovePragmaHandler(PragmaHandler *Handler) { auto I = Handlers.find(Handler->getName()); assert(I != Handlers.end() && "Handler not registered in this namespace"); // Release ownership back to the caller. I->getValue().release(); Handlers.erase(I); } void PragmaNamespace::HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) { // Read the 'namespace' that the directive is in, e.g. STDC. Do not macro // expand it, the user can have a STDC #define, that should not affect this. PP.LexUnexpandedToken(Tok); // Get the handler for this token. If there is no handler, ignore the pragma. PragmaHandler *Handler = FindHandler(Tok.getIdentifierInfo() ? Tok.getIdentifierInfo()->getName() : StringRef(), /*IgnoreNull=*/false); if (!Handler) { PP.Diag(Tok, diag::warn_pragma_ignored); return; } // Otherwise, pass it down. Handler->HandlePragma(PP, Introducer, Tok); } //===----------------------------------------------------------------------===// // Preprocessor Pragma Directive Handling. //===----------------------------------------------------------------------===// namespace { // TokenCollector provides the option to collect tokens that were "read" // and return them to the stream to be read later. // Currently used when reading _Pragma/__pragma directives. struct TokenCollector { Preprocessor &Self; bool Collect; SmallVector Tokens; Token &Tok; void lex() { if (Collect) Tokens.push_back(Tok); Self.Lex(Tok); } void revert() { assert(Collect && "did not collect tokens"); assert(!Tokens.empty() && "collected unexpected number of tokens"); // Push the ( "string" ) tokens into the token stream. auto Toks = std::make_unique(Tokens.size()); std::copy(Tokens.begin() + 1, Tokens.end(), Toks.get()); Toks[Tokens.size() - 1] = Tok; Self.EnterTokenStream(std::move(Toks), Tokens.size(), /*DisableMacroExpansion*/ true, /*IsReinject*/ true); // ... and return the pragma token unchanged. Tok = *Tokens.begin(); } }; } // namespace /// HandlePragmaDirective - The "\#pragma" directive has been parsed. Lex the /// rest of the pragma, passing it to the registered pragma handlers. void Preprocessor::HandlePragmaDirective(PragmaIntroducer Introducer) { if (Callbacks) Callbacks->PragmaDirective(Introducer.Loc, Introducer.Kind); if (!PragmasEnabled) return; ++NumPragma; // Invoke the first level of pragma handlers which reads the namespace id. Token Tok; PragmaHandlers->HandlePragma(*this, Introducer, Tok); // If the pragma handler didn't read the rest of the line, consume it now. if ((CurTokenLexer && CurTokenLexer->isParsingPreprocessorDirective()) || (CurPPLexer && CurPPLexer->ParsingPreprocessorDirective)) DiscardUntilEndOfDirective(); } /// Handle_Pragma - Read a _Pragma directive, slice it up, process it, then /// return the first token after the directive. The _Pragma token has just /// been read into 'Tok'. void Preprocessor::Handle_Pragma(Token &Tok) { // C11 6.10.3.4/3: // all pragma unary operator expressions within [a completely // macro-replaced preprocessing token sequence] are [...] processed [after // rescanning is complete] // // This means that we execute _Pragma operators in two cases: // // 1) on token sequences that would otherwise be produced as the output of // phase 4 of preprocessing, and // 2) on token sequences formed as the macro-replaced token sequence of a // macro argument // // Case #2 appears to be a wording bug: only _Pragmas that would survive to // the end of phase 4 should actually be executed. Discussion on the WG14 // mailing list suggests that a _Pragma operator is notionally checked early, // but only pragmas that survive to the end of phase 4 should be executed. // // In Case #2, we check the syntax now, but then put the tokens back into the // token stream for later consumption. TokenCollector Toks = {*this, InMacroArgPreExpansion, {}, Tok}; // Remember the pragma token location. SourceLocation PragmaLoc = Tok.getLocation(); // Read the '('. Toks.lex(); if (Tok.isNot(tok::l_paren)) { Diag(PragmaLoc, diag::err__Pragma_malformed); return; } // Read the '"..."'. Toks.lex(); if (!tok::isStringLiteral(Tok.getKind())) { Diag(PragmaLoc, diag::err__Pragma_malformed); // Skip bad tokens, and the ')', if present. if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::eof)) Lex(Tok); while (Tok.isNot(tok::r_paren) && !Tok.isAtStartOfLine() && Tok.isNot(tok::eof)) Lex(Tok); if (Tok.is(tok::r_paren)) Lex(Tok); return; } if (Tok.hasUDSuffix()) { Diag(Tok, diag::err_invalid_string_udl); // Skip this token, and the ')', if present. Lex(Tok); if (Tok.is(tok::r_paren)) Lex(Tok); return; } // Remember the string. Token StrTok = Tok; // Read the ')'. Toks.lex(); if (Tok.isNot(tok::r_paren)) { Diag(PragmaLoc, diag::err__Pragma_malformed); return; } // If we're expanding a macro argument, put the tokens back. if (InMacroArgPreExpansion) { Toks.revert(); return; } SourceLocation RParenLoc = Tok.getLocation(); std::string StrVal = getSpelling(StrTok); // The _Pragma is lexically sound. Destringize according to C11 6.10.9.1: // "The string literal is destringized by deleting any encoding prefix, // deleting the leading and trailing double-quotes, replacing each escape // sequence \" by a double-quote, and replacing each escape sequence \\ by a // single backslash." if (StrVal[0] == 'L' || StrVal[0] == 'U' || (StrVal[0] == 'u' && StrVal[1] != '8')) StrVal.erase(StrVal.begin()); else if (StrVal[0] == 'u') StrVal.erase(StrVal.begin(), StrVal.begin() + 2); if (StrVal[0] == 'R') { // FIXME: C++11 does not specify how to handle raw-string-literals here. // We strip off the 'R', the quotes, the d-char-sequences, and the parens. assert(StrVal[1] == '"' && StrVal[StrVal.size() - 1] == '"' && "Invalid raw string token!"); // Measure the length of the d-char-sequence. unsigned NumDChars = 0; while (StrVal[2 + NumDChars] != '(') { assert(NumDChars < (StrVal.size() - 5) / 2 && "Invalid raw string token!"); ++NumDChars; } assert(StrVal[StrVal.size() - 2 - NumDChars] == ')'); // Remove 'R " d-char-sequence' and 'd-char-sequence "'. We'll replace the // parens below. StrVal.erase(0, 2 + NumDChars); StrVal.erase(StrVal.size() - 1 - NumDChars); } else { assert(StrVal[0] == '"' && StrVal[StrVal.size()-1] == '"' && "Invalid string token!"); // Remove escaped quotes and escapes. unsigned ResultPos = 1; for (size_t i = 1, e = StrVal.size() - 1; i != e; ++i) { // Skip escapes. \\ -> '\' and \" -> '"'. if (StrVal[i] == '\\' && i + 1 < e && (StrVal[i + 1] == '\\' || StrVal[i + 1] == '"')) ++i; StrVal[ResultPos++] = StrVal[i]; } StrVal.erase(StrVal.begin() + ResultPos, StrVal.end() - 1); } // Remove the front quote, replacing it with a space, so that the pragma // contents appear to have a space before them. StrVal[0] = ' '; // Replace the terminating quote with a \n. StrVal[StrVal.size()-1] = '\n'; // Plop the string (including the newline and trailing null) into a buffer // where we can lex it. Token TmpTok; TmpTok.startToken(); CreateString(StrVal, TmpTok); SourceLocation TokLoc = TmpTok.getLocation(); // Make and enter a lexer object so that we lex and expand the tokens just // like any others. Lexer *TL = Lexer::Create_PragmaLexer(TokLoc, PragmaLoc, RParenLoc, StrVal.size(), *this); EnterSourceFileWithLexer(TL, nullptr); // With everything set up, lex this as a #pragma directive. HandlePragmaDirective({PIK__Pragma, PragmaLoc}); // Finally, return whatever came after the pragma directive. return Lex(Tok); } /// HandleMicrosoft__pragma - Like Handle_Pragma except the pragma text /// is not enclosed within a string literal. void Preprocessor::HandleMicrosoft__pragma(Token &Tok) { // During macro pre-expansion, check the syntax now but put the tokens back // into the token stream for later consumption. Same as Handle_Pragma. TokenCollector Toks = {*this, InMacroArgPreExpansion, {}, Tok}; // Remember the pragma token location. SourceLocation PragmaLoc = Tok.getLocation(); // Read the '('. Toks.lex(); if (Tok.isNot(tok::l_paren)) { Diag(PragmaLoc, diag::err__Pragma_malformed); return; } // Get the tokens enclosed within the __pragma(), as well as the final ')'. SmallVector PragmaToks; int NumParens = 0; Toks.lex(); while (Tok.isNot(tok::eof)) { PragmaToks.push_back(Tok); if (Tok.is(tok::l_paren)) NumParens++; else if (Tok.is(tok::r_paren) && NumParens-- == 0) break; Toks.lex(); } if (Tok.is(tok::eof)) { Diag(PragmaLoc, diag::err_unterminated___pragma); return; } // If we're expanding a macro argument, put the tokens back. if (InMacroArgPreExpansion) { Toks.revert(); return; } PragmaToks.front().setFlag(Token::LeadingSpace); // Replace the ')' with an EOD to mark the end of the pragma. PragmaToks.back().setKind(tok::eod); Token *TokArray = new Token[PragmaToks.size()]; std::copy(PragmaToks.begin(), PragmaToks.end(), TokArray); // Push the tokens onto the stack. EnterTokenStream(TokArray, PragmaToks.size(), true, true, /*IsReinject*/ false); // With everything set up, lex this as a #pragma directive. HandlePragmaDirective({PIK___pragma, PragmaLoc}); // Finally, return whatever came after the pragma directive. return Lex(Tok); } /// HandlePragmaOnce - Handle \#pragma once. OnceTok is the 'once'. void Preprocessor::HandlePragmaOnce(Token &OnceTok) { // Don't honor the 'once' when handling the primary source file, unless // this is a prefix to a TU, which indicates we're generating a PCH file, or // when the main file is a header (e.g. when -xc-header is provided on the // commandline). if (isInPrimaryFile() && TUKind != TU_Prefix && !getLangOpts().IsHeaderFile) { Diag(OnceTok, diag::pp_pragma_once_in_main_file); return; } // Get the current file lexer we're looking at. Ignore _Pragma 'files' etc. // Mark the file as a once-only file now. HeaderInfo.MarkFileIncludeOnce(getCurrentFileLexer()->getFileEntry()); } void Preprocessor::HandlePragmaMark() { assert(CurPPLexer && "No current lexer?"); CurLexer->ReadToEndOfLine(); } /// HandlePragmaPoison - Handle \#pragma GCC poison. PoisonTok is the 'poison'. void Preprocessor::HandlePragmaPoison() { Token Tok; while (true) { // Read the next token to poison. While doing this, pretend that we are // skipping while reading the identifier to poison. // This avoids errors on code like: // #pragma GCC poison X // #pragma GCC poison X if (CurPPLexer) CurPPLexer->LexingRawMode = true; LexUnexpandedToken(Tok); if (CurPPLexer) CurPPLexer->LexingRawMode = false; // If we reached the end of line, we're done. if (Tok.is(tok::eod)) return; // Can only poison identifiers. if (Tok.isNot(tok::raw_identifier)) { Diag(Tok, diag::err_pp_invalid_poison); return; } // Look up the identifier info for the token. We disabled identifier lookup // by saying we're skipping contents, so we need to do this manually. IdentifierInfo *II = LookUpIdentifierInfo(Tok); // Already poisoned. if (II->isPoisoned()) continue; // If this is a macro identifier, emit a warning. if (isMacroDefined(II)) Diag(Tok, diag::pp_poisoning_existing_macro); // Finally, poison it! II->setIsPoisoned(); if (II->isFromAST()) II->setChangedSinceDeserialization(); } } /// HandlePragmaSystemHeader - Implement \#pragma GCC system_header. We know /// that the whole directive has been parsed. void Preprocessor::HandlePragmaSystemHeader(Token &SysHeaderTok) { if (isInPrimaryFile()) { Diag(SysHeaderTok, diag::pp_pragma_sysheader_in_main_file); return; } // Get the current file lexer we're looking at. Ignore _Pragma 'files' etc. PreprocessorLexer *TheLexer = getCurrentFileLexer(); // Mark the file as a system header. HeaderInfo.MarkFileSystemHeader(TheLexer->getFileEntry()); PresumedLoc PLoc = SourceMgr.getPresumedLoc(SysHeaderTok.getLocation()); if (PLoc.isInvalid()) return; unsigned FilenameID = SourceMgr.getLineTableFilenameID(PLoc.getFilename()); // Notify the client, if desired, that we are in a new source file. if (Callbacks) Callbacks->FileChanged(SysHeaderTok.getLocation(), PPCallbacks::SystemHeaderPragma, SrcMgr::C_System); // Emit a line marker. This will change any source locations from this point // forward to realize they are in a system header. // Create a line note with this information. SourceMgr.AddLineNote(SysHeaderTok.getLocation(), PLoc.getLine() + 1, FilenameID, /*IsEntry=*/false, /*IsExit=*/false, SrcMgr::C_System); } /// HandlePragmaDependency - Handle \#pragma GCC dependency "foo" blah. void Preprocessor::HandlePragmaDependency(Token &DependencyTok) { Token FilenameTok; if (LexHeaderName(FilenameTok, /*AllowConcatenation*/false)) return; // If the next token wasn't a header-name, diagnose the error. if (FilenameTok.isNot(tok::header_name)) { Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename); return; } // Reserve a buffer to get the spelling. SmallString<128> FilenameBuffer; bool Invalid = false; StringRef Filename = getSpelling(FilenameTok, FilenameBuffer, &Invalid); if (Invalid) return; bool isAngled = GetIncludeFilenameSpelling(FilenameTok.getLocation(), Filename); // If GetIncludeFilenameSpelling set the start ptr to null, there was an // error. if (Filename.empty()) return; // Search include directories for this file. const DirectoryLookup *CurDir; Optional File = LookupFile(FilenameTok.getLocation(), Filename, isAngled, nullptr, nullptr, CurDir, nullptr, nullptr, nullptr, nullptr, nullptr); if (!File) { if (!SuppressIncludeNotFoundError) Diag(FilenameTok, diag::err_pp_file_not_found) << Filename; return; } const FileEntry *CurFile = getCurrentFileLexer()->getFileEntry(); // If this file is older than the file it depends on, emit a diagnostic. if (CurFile && CurFile->getModificationTime() < File->getModificationTime()) { // Lex tokens at the end of the message and include them in the message. std::string Message; Lex(DependencyTok); while (DependencyTok.isNot(tok::eod)) { Message += getSpelling(DependencyTok) + " "; Lex(DependencyTok); } // Remove the trailing ' ' if present. if (!Message.empty()) Message.erase(Message.end()-1); Diag(FilenameTok, diag::pp_out_of_date_dependency) << Message; } } /// ParsePragmaPushOrPopMacro - Handle parsing of pragma push_macro/pop_macro. /// Return the IdentifierInfo* associated with the macro to push or pop. IdentifierInfo *Preprocessor::ParsePragmaPushOrPopMacro(Token &Tok) { // Remember the pragma token location. Token PragmaTok = Tok; // Read the '('. Lex(Tok); if (Tok.isNot(tok::l_paren)) { Diag(PragmaTok.getLocation(), diag::err_pragma_push_pop_macro_malformed) << getSpelling(PragmaTok); return nullptr; } // Read the macro name string. Lex(Tok); if (Tok.isNot(tok::string_literal)) { Diag(PragmaTok.getLocation(), diag::err_pragma_push_pop_macro_malformed) << getSpelling(PragmaTok); return nullptr; } if (Tok.hasUDSuffix()) { Diag(Tok, diag::err_invalid_string_udl); return nullptr; } // Remember the macro string. std::string StrVal = getSpelling(Tok); // Read the ')'. Lex(Tok); if (Tok.isNot(tok::r_paren)) { Diag(PragmaTok.getLocation(), diag::err_pragma_push_pop_macro_malformed) << getSpelling(PragmaTok); return nullptr; } assert(StrVal[0] == '"' && StrVal[StrVal.size()-1] == '"' && "Invalid string token!"); // Create a Token from the string. Token MacroTok; MacroTok.startToken(); MacroTok.setKind(tok::raw_identifier); CreateString(StringRef(&StrVal[1], StrVal.size() - 2), MacroTok); // Get the IdentifierInfo of MacroToPushTok. return LookUpIdentifierInfo(MacroTok); } /// Handle \#pragma push_macro. /// /// The syntax is: /// \code /// #pragma push_macro("macro") /// \endcode void Preprocessor::HandlePragmaPushMacro(Token &PushMacroTok) { // Parse the pragma directive and get the macro IdentifierInfo*. IdentifierInfo *IdentInfo = ParsePragmaPushOrPopMacro(PushMacroTok); if (!IdentInfo) return; // Get the MacroInfo associated with IdentInfo. MacroInfo *MI = getMacroInfo(IdentInfo); if (MI) { // Allow the original MacroInfo to be redefined later. MI->setIsAllowRedefinitionsWithoutWarning(true); } // Push the cloned MacroInfo so we can retrieve it later. PragmaPushMacroInfo[IdentInfo].push_back(MI); } /// Handle \#pragma pop_macro. /// /// The syntax is: /// \code /// #pragma pop_macro("macro") /// \endcode void Preprocessor::HandlePragmaPopMacro(Token &PopMacroTok) { SourceLocation MessageLoc = PopMacroTok.getLocation(); // Parse the pragma directive and get the macro IdentifierInfo*. IdentifierInfo *IdentInfo = ParsePragmaPushOrPopMacro(PopMacroTok); if (!IdentInfo) return; // Find the vector associated with the macro. llvm::DenseMap>::iterator iter = PragmaPushMacroInfo.find(IdentInfo); if (iter != PragmaPushMacroInfo.end()) { // Forget the MacroInfo currently associated with IdentInfo. if (MacroInfo *MI = getMacroInfo(IdentInfo)) { if (MI->isWarnIfUnused()) WarnUnusedMacroLocs.erase(MI->getDefinitionLoc()); appendMacroDirective(IdentInfo, AllocateUndefMacroDirective(MessageLoc)); } // Get the MacroInfo we want to reinstall. MacroInfo *MacroToReInstall = iter->second.back(); if (MacroToReInstall) // Reinstall the previously pushed macro. appendDefMacroDirective(IdentInfo, MacroToReInstall, MessageLoc); // Pop PragmaPushMacroInfo stack. iter->second.pop_back(); if (iter->second.empty()) PragmaPushMacroInfo.erase(iter); } else { Diag(MessageLoc, diag::warn_pragma_pop_macro_no_push) << IdentInfo->getName(); } } void Preprocessor::HandlePragmaIncludeAlias(Token &Tok) { // We will either get a quoted filename or a bracketed filename, and we // have to track which we got. The first filename is the source name, // and the second name is the mapped filename. If the first is quoted, // the second must be as well (cannot mix and match quotes and brackets). // Get the open paren Lex(Tok); if (Tok.isNot(tok::l_paren)) { Diag(Tok, diag::warn_pragma_include_alias_expected) << "("; return; } // We expect either a quoted string literal, or a bracketed name Token SourceFilenameTok; if (LexHeaderName(SourceFilenameTok)) return; StringRef SourceFileName; SmallString<128> FileNameBuffer; if (SourceFilenameTok.is(tok::header_name)) { SourceFileName = getSpelling(SourceFilenameTok, FileNameBuffer); } else { Diag(Tok, diag::warn_pragma_include_alias_expected_filename); return; } FileNameBuffer.clear(); // Now we expect a comma, followed by another include name Lex(Tok); if (Tok.isNot(tok::comma)) { Diag(Tok, diag::warn_pragma_include_alias_expected) << ","; return; } Token ReplaceFilenameTok; if (LexHeaderName(ReplaceFilenameTok)) return; StringRef ReplaceFileName; if (ReplaceFilenameTok.is(tok::header_name)) { ReplaceFileName = getSpelling(ReplaceFilenameTok, FileNameBuffer); } else { Diag(Tok, diag::warn_pragma_include_alias_expected_filename); return; } // Finally, we expect the closing paren Lex(Tok); if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::warn_pragma_include_alias_expected) << ")"; return; } // Now that we have the source and target filenames, we need to make sure // they're both of the same type (angled vs non-angled) StringRef OriginalSource = SourceFileName; bool SourceIsAngled = GetIncludeFilenameSpelling(SourceFilenameTok.getLocation(), SourceFileName); bool ReplaceIsAngled = GetIncludeFilenameSpelling(ReplaceFilenameTok.getLocation(), ReplaceFileName); if (!SourceFileName.empty() && !ReplaceFileName.empty() && (SourceIsAngled != ReplaceIsAngled)) { unsigned int DiagID; if (SourceIsAngled) DiagID = diag::warn_pragma_include_alias_mismatch_angle; else DiagID = diag::warn_pragma_include_alias_mismatch_quote; Diag(SourceFilenameTok.getLocation(), DiagID) << SourceFileName << ReplaceFileName; return; } // Now we can let the include handler know about this mapping getHeaderSearchInfo().AddIncludeAlias(OriginalSource, ReplaceFileName); } // Lex a component of a module name: either an identifier or a string literal; // for components that can be expressed both ways, the two forms are equivalent. static bool LexModuleNameComponent( Preprocessor &PP, Token &Tok, std::pair &ModuleNameComponent, bool First) { PP.LexUnexpandedToken(Tok); if (Tok.is(tok::string_literal) && !Tok.hasUDSuffix()) { StringLiteralParser Literal(Tok, PP); if (Literal.hadError) return true; ModuleNameComponent = std::make_pair( PP.getIdentifierInfo(Literal.GetString()), Tok.getLocation()); } else if (!Tok.isAnnotation() && Tok.getIdentifierInfo()) { ModuleNameComponent = std::make_pair(Tok.getIdentifierInfo(), Tok.getLocation()); } else { PP.Diag(Tok.getLocation(), diag::err_pp_expected_module_name) << First; return true; } return false; } static bool LexModuleName( Preprocessor &PP, Token &Tok, llvm::SmallVectorImpl> &ModuleName) { while (true) { std::pair NameComponent; if (LexModuleNameComponent(PP, Tok, NameComponent, ModuleName.empty())) return true; ModuleName.push_back(NameComponent); PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::period)) return false; } } void Preprocessor::HandlePragmaModuleBuild(Token &Tok) { SourceLocation Loc = Tok.getLocation(); std::pair ModuleNameLoc; if (LexModuleNameComponent(*this, Tok, ModuleNameLoc, true)) return; IdentifierInfo *ModuleName = ModuleNameLoc.first; LexUnexpandedToken(Tok); if (Tok.isNot(tok::eod)) { Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; DiscardUntilEndOfDirective(); } CurLexer->LexingRawMode = true; auto TryConsumeIdentifier = [&](StringRef Ident) -> bool { if (Tok.getKind() != tok::raw_identifier || Tok.getRawIdentifier() != Ident) return false; CurLexer->Lex(Tok); return true; }; // Scan forward looking for the end of the module. const char *Start = CurLexer->getBufferLocation(); const char *End = nullptr; unsigned NestingLevel = 1; while (true) { End = CurLexer->getBufferLocation(); CurLexer->Lex(Tok); if (Tok.is(tok::eof)) { Diag(Loc, diag::err_pp_module_build_missing_end); break; } if (Tok.isNot(tok::hash) || !Tok.isAtStartOfLine()) { // Token was part of module; keep going. continue; } // We hit something directive-shaped; check to see if this is the end // of the module build. CurLexer->ParsingPreprocessorDirective = true; CurLexer->Lex(Tok); if (TryConsumeIdentifier("pragma") && TryConsumeIdentifier("clang") && TryConsumeIdentifier("module")) { if (TryConsumeIdentifier("build")) // #pragma clang module build -> entering a nested module build. ++NestingLevel; else if (TryConsumeIdentifier("endbuild")) { // #pragma clang module endbuild -> leaving a module build. if (--NestingLevel == 0) break; } // We should either be looking at the EOD or more of the current directive // preceding the EOD. Either way we can ignore this token and keep going. assert(Tok.getKind() != tok::eof && "missing EOD before EOF"); } } CurLexer->LexingRawMode = false; // Load the extracted text as a preprocessed module. assert(CurLexer->getBuffer().begin() <= Start && Start <= CurLexer->getBuffer().end() && CurLexer->getBuffer().begin() <= End && End <= CurLexer->getBuffer().end() && "module source range not contained within same file buffer"); TheModuleLoader.createModuleFromSource(Loc, ModuleName->getName(), StringRef(Start, End - Start)); } void Preprocessor::HandlePragmaHdrstop(Token &Tok) { Lex(Tok); if (Tok.is(tok::l_paren)) { Diag(Tok.getLocation(), diag::warn_pp_hdrstop_filename_ignored); std::string FileName; if (!LexStringLiteral(Tok, FileName, "pragma hdrstop", false)) return; if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_expected) << tok::r_paren; return; } Lex(Tok); } if (Tok.isNot(tok::eod)) Diag(Tok.getLocation(), diag::ext_pp_extra_tokens_at_eol) << "pragma hdrstop"; if (creatingPCHWithPragmaHdrStop() && SourceMgr.isInMainFile(Tok.getLocation())) { assert(CurLexer && "no lexer for #pragma hdrstop processing"); Token &Result = Tok; Result.startToken(); CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd, tok::eof); CurLexer->cutOffLexing(); } if (usingPCHWithPragmaHdrStop()) SkippingUntilPragmaHdrStop = false; } /// AddPragmaHandler - Add the specified pragma handler to the preprocessor. /// If 'Namespace' is non-null, then it is a token required to exist on the /// pragma line before the pragma string starts, e.g. "STDC" or "GCC". void Preprocessor::AddPragmaHandler(StringRef Namespace, PragmaHandler *Handler) { PragmaNamespace *InsertNS = PragmaHandlers.get(); // If this is specified to be in a namespace, step down into it. if (!Namespace.empty()) { // If there is already a pragma handler with the name of this namespace, // we either have an error (directive with the same name as a namespace) or // we already have the namespace to insert into. if (PragmaHandler *Existing = PragmaHandlers->FindHandler(Namespace)) { InsertNS = Existing->getIfNamespace(); assert(InsertNS != nullptr && "Cannot have a pragma namespace and pragma" " handler with the same name!"); } else { // Otherwise, this namespace doesn't exist yet, create and insert the // handler for it. InsertNS = new PragmaNamespace(Namespace); PragmaHandlers->AddPragma(InsertNS); } } // Check to make sure we don't already have a pragma for this identifier. assert(!InsertNS->FindHandler(Handler->getName()) && "Pragma handler already exists for this identifier!"); InsertNS->AddPragma(Handler); } /// RemovePragmaHandler - Remove the specific pragma handler from the /// preprocessor. If \arg Namespace is non-null, then it should be the /// namespace that \arg Handler was added to. It is an error to remove /// a handler that has not been registered. void Preprocessor::RemovePragmaHandler(StringRef Namespace, PragmaHandler *Handler) { PragmaNamespace *NS = PragmaHandlers.get(); // If this is specified to be in a namespace, step down into it. if (!Namespace.empty()) { PragmaHandler *Existing = PragmaHandlers->FindHandler(Namespace); assert(Existing && "Namespace containing handler does not exist!"); NS = Existing->getIfNamespace(); assert(NS && "Invalid namespace, registered as a regular pragma handler!"); } NS->RemovePragmaHandler(Handler); // If this is a non-default namespace and it is now empty, remove it. if (NS != PragmaHandlers.get() && NS->IsEmpty()) { PragmaHandlers->RemovePragmaHandler(NS); delete NS; } } bool Preprocessor::LexOnOffSwitch(tok::OnOffSwitch &Result) { Token Tok; LexUnexpandedToken(Tok); if (Tok.isNot(tok::identifier)) { Diag(Tok, diag::ext_on_off_switch_syntax); return true; } IdentifierInfo *II = Tok.getIdentifierInfo(); if (II->isStr("ON")) Result = tok::OOS_ON; else if (II->isStr("OFF")) Result = tok::OOS_OFF; else if (II->isStr("DEFAULT")) Result = tok::OOS_DEFAULT; else { Diag(Tok, diag::ext_on_off_switch_syntax); return true; } // Verify that this is followed by EOD. LexUnexpandedToken(Tok); if (Tok.isNot(tok::eod)) Diag(Tok, diag::ext_pragma_syntax_eod); return false; } namespace { /// PragmaOnceHandler - "\#pragma once" marks the file as atomically included. struct PragmaOnceHandler : public PragmaHandler { PragmaOnceHandler() : PragmaHandler("once") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &OnceTok) override { PP.CheckEndOfDirective("pragma once"); PP.HandlePragmaOnce(OnceTok); } }; /// PragmaMarkHandler - "\#pragma mark ..." is ignored by the compiler, and the /// rest of the line is not lexed. struct PragmaMarkHandler : public PragmaHandler { PragmaMarkHandler() : PragmaHandler("mark") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &MarkTok) override { PP.HandlePragmaMark(); } }; /// PragmaPoisonHandler - "\#pragma poison x" marks x as not usable. struct PragmaPoisonHandler : public PragmaHandler { PragmaPoisonHandler() : PragmaHandler("poison") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &PoisonTok) override { PP.HandlePragmaPoison(); } }; /// PragmaSystemHeaderHandler - "\#pragma system_header" marks the current file /// as a system header, which silences warnings in it. struct PragmaSystemHeaderHandler : public PragmaHandler { PragmaSystemHeaderHandler() : PragmaHandler("system_header") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &SHToken) override { PP.HandlePragmaSystemHeader(SHToken); PP.CheckEndOfDirective("pragma"); } }; struct PragmaDependencyHandler : public PragmaHandler { PragmaDependencyHandler() : PragmaHandler("dependency") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &DepToken) override { PP.HandlePragmaDependency(DepToken); } }; struct PragmaDebugHandler : public PragmaHandler { PragmaDebugHandler() : PragmaHandler("__debug") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &DebugToken) override { Token Tok; PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::identifier)) { PP.Diag(Tok, diag::warn_pragma_diagnostic_invalid); return; } IdentifierInfo *II = Tok.getIdentifierInfo(); if (II->isStr("assert")) { if (!PP.getPreprocessorOpts().DisablePragmaDebugCrash) llvm_unreachable("This is an assertion!"); } else if (II->isStr("crash")) { llvm::Timer T("crash", "pragma crash"); llvm::TimeRegion R(&T); if (!PP.getPreprocessorOpts().DisablePragmaDebugCrash) LLVM_BUILTIN_TRAP; } else if (II->isStr("parser_crash")) { if (!PP.getPreprocessorOpts().DisablePragmaDebugCrash) { Token Crasher; Crasher.startToken(); Crasher.setKind(tok::annot_pragma_parser_crash); Crasher.setAnnotationRange(SourceRange(Tok.getLocation())); PP.EnterToken(Crasher, /*IsReinject*/ false); } } else if (II->isStr("dump")) { Token Identifier; PP.LexUnexpandedToken(Identifier); if (auto *DumpII = Identifier.getIdentifierInfo()) { Token DumpAnnot; DumpAnnot.startToken(); DumpAnnot.setKind(tok::annot_pragma_dump); DumpAnnot.setAnnotationRange( SourceRange(Tok.getLocation(), Identifier.getLocation())); DumpAnnot.setAnnotationValue(DumpII); PP.DiscardUntilEndOfDirective(); PP.EnterToken(DumpAnnot, /*IsReinject*/false); } else { PP.Diag(Identifier, diag::warn_pragma_debug_missing_argument) << II->getName(); } } else if (II->isStr("diag_mapping")) { Token DiagName; PP.LexUnexpandedToken(DiagName); if (DiagName.is(tok::eod)) PP.getDiagnostics().dump(); else if (DiagName.is(tok::string_literal) && !DiagName.hasUDSuffix()) { StringLiteralParser Literal(DiagName, PP); if (Literal.hadError) return; PP.getDiagnostics().dump(Literal.GetString()); } else { PP.Diag(DiagName, diag::warn_pragma_debug_missing_argument) << II->getName(); } } else if (II->isStr("llvm_fatal_error")) { if (!PP.getPreprocessorOpts().DisablePragmaDebugCrash) llvm::report_fatal_error("#pragma clang __debug llvm_fatal_error"); } else if (II->isStr("llvm_unreachable")) { if (!PP.getPreprocessorOpts().DisablePragmaDebugCrash) llvm_unreachable("#pragma clang __debug llvm_unreachable"); } else if (II->isStr("macro")) { Token MacroName; PP.LexUnexpandedToken(MacroName); auto *MacroII = MacroName.getIdentifierInfo(); if (MacroII) PP.dumpMacroInfo(MacroII); else PP.Diag(MacroName, diag::warn_pragma_debug_missing_argument) << II->getName(); } else if (II->isStr("module_map")) { llvm::SmallVector, 8> ModuleName; if (LexModuleName(PP, Tok, ModuleName)) return; ModuleMap &MM = PP.getHeaderSearchInfo().getModuleMap(); Module *M = nullptr; for (auto IIAndLoc : ModuleName) { M = MM.lookupModuleQualified(IIAndLoc.first->getName(), M); if (!M) { PP.Diag(IIAndLoc.second, diag::warn_pragma_debug_unknown_module) << IIAndLoc.first; return; } } M->dump(); } else if (II->isStr("overflow_stack")) { if (!PP.getPreprocessorOpts().DisablePragmaDebugCrash) DebugOverflowStack(); } else if (II->isStr("captured")) { HandleCaptured(PP); } else { PP.Diag(Tok, diag::warn_pragma_debug_unexpected_command) << II->getName(); } PPCallbacks *Callbacks = PP.getPPCallbacks(); if (Callbacks) Callbacks->PragmaDebug(Tok.getLocation(), II->getName()); } void HandleCaptured(Preprocessor &PP) { Token Tok; PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::eod)) { PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma clang __debug captured"; return; } SourceLocation NameLoc = Tok.getLocation(); MutableArrayRef Toks( PP.getPreprocessorAllocator().Allocate(1), 1); Toks[0].startToken(); Toks[0].setKind(tok::annot_pragma_captured); Toks[0].setLocation(NameLoc); PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true, /*IsReinject=*/false); } // Disable MSVC warning about runtime stack overflow. #ifdef _MSC_VER #pragma warning(disable : 4717) #endif static void DebugOverflowStack(void (*P)() = nullptr) { void (*volatile Self)(void(*P)()) = DebugOverflowStack; Self(reinterpret_cast(Self)); } #ifdef _MSC_VER #pragma warning(default : 4717) #endif }; /// PragmaDiagnosticHandler - e.g. '\#pragma GCC diagnostic ignored "-Wformat"' struct PragmaDiagnosticHandler : public PragmaHandler { private: const char *Namespace; public: explicit PragmaDiagnosticHandler(const char *NS) : PragmaHandler("diagnostic"), Namespace(NS) {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &DiagToken) override { SourceLocation DiagLoc = DiagToken.getLocation(); Token Tok; PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::identifier)) { PP.Diag(Tok, diag::warn_pragma_diagnostic_invalid); return; } IdentifierInfo *II = Tok.getIdentifierInfo(); PPCallbacks *Callbacks = PP.getPPCallbacks(); if (II->isStr("pop")) { if (!PP.getDiagnostics().popMappings(DiagLoc)) PP.Diag(Tok, diag::warn_pragma_diagnostic_cannot_pop); else if (Callbacks) Callbacks->PragmaDiagnosticPop(DiagLoc, Namespace); return; } else if (II->isStr("push")) { PP.getDiagnostics().pushMappings(DiagLoc); if (Callbacks) Callbacks->PragmaDiagnosticPush(DiagLoc, Namespace); return; } diag::Severity SV = llvm::StringSwitch(II->getName()) .Case("ignored", diag::Severity::Ignored) .Case("warning", diag::Severity::Warning) .Case("error", diag::Severity::Error) .Case("fatal", diag::Severity::Fatal) .Default(diag::Severity()); if (SV == diag::Severity()) { PP.Diag(Tok, diag::warn_pragma_diagnostic_invalid); return; } PP.LexUnexpandedToken(Tok); SourceLocation StringLoc = Tok.getLocation(); std::string WarningName; if (!PP.FinishLexStringLiteral(Tok, WarningName, "pragma diagnostic", /*AllowMacroExpansion=*/false)) return; if (Tok.isNot(tok::eod)) { PP.Diag(Tok.getLocation(), diag::warn_pragma_diagnostic_invalid_token); return; } if (WarningName.size() < 3 || WarningName[0] != '-' || (WarningName[1] != 'W' && WarningName[1] != 'R')) { PP.Diag(StringLoc, diag::warn_pragma_diagnostic_invalid_option); return; } diag::Flavor Flavor = WarningName[1] == 'W' ? diag::Flavor::WarningOrError : diag::Flavor::Remark; StringRef Group = StringRef(WarningName).substr(2); bool unknownDiag = false; if (Group == "everything") { // Special handling for pragma clang diagnostic ... "-Weverything". // There is no formal group named "everything", so there has to be a // special case for it. PP.getDiagnostics().setSeverityForAll(Flavor, SV, DiagLoc); } else unknownDiag = PP.getDiagnostics().setSeverityForGroup(Flavor, Group, SV, DiagLoc); if (unknownDiag) PP.Diag(StringLoc, diag::warn_pragma_diagnostic_unknown_warning) << WarningName; else if (Callbacks) Callbacks->PragmaDiagnostic(DiagLoc, Namespace, SV, WarningName); } }; /// "\#pragma hdrstop []" struct PragmaHdrstopHandler : public PragmaHandler { PragmaHdrstopHandler() : PragmaHandler("hdrstop") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &DepToken) override { PP.HandlePragmaHdrstop(DepToken); } }; /// "\#pragma warning(...)". MSVC's diagnostics do not map cleanly to clang's /// diagnostics, so we don't really implement this pragma. We parse it and /// ignore it to avoid -Wunknown-pragma warnings. struct PragmaWarningHandler : public PragmaHandler { PragmaWarningHandler() : PragmaHandler("warning") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { // Parse things like: // warning(push, 1) // warning(pop) // warning(disable : 1 2 3 ; error : 4 5 6 ; suppress : 7 8 9) SourceLocation DiagLoc = Tok.getLocation(); PPCallbacks *Callbacks = PP.getPPCallbacks(); PP.Lex(Tok); if (Tok.isNot(tok::l_paren)) { PP.Diag(Tok, diag::warn_pragma_warning_expected) << "("; return; } PP.Lex(Tok); IdentifierInfo *II = Tok.getIdentifierInfo(); if (II && II->isStr("push")) { // #pragma warning( push[ ,n ] ) int Level = -1; PP.Lex(Tok); if (Tok.is(tok::comma)) { PP.Lex(Tok); uint64_t Value; if (Tok.is(tok::numeric_constant) && PP.parseSimpleIntegerLiteral(Tok, Value)) Level = int(Value); if (Level < 0 || Level > 4) { PP.Diag(Tok, diag::warn_pragma_warning_push_level); return; } } if (Callbacks) Callbacks->PragmaWarningPush(DiagLoc, Level); } else if (II && II->isStr("pop")) { // #pragma warning( pop ) PP.Lex(Tok); if (Callbacks) Callbacks->PragmaWarningPop(DiagLoc); } else { // #pragma warning( warning-specifier : warning-number-list // [; warning-specifier : warning-number-list...] ) while (true) { II = Tok.getIdentifierInfo(); if (!II && !Tok.is(tok::numeric_constant)) { PP.Diag(Tok, diag::warn_pragma_warning_spec_invalid); return; } // Figure out which warning specifier this is. bool SpecifierValid; StringRef Specifier; llvm::SmallString<1> SpecifierBuf; if (II) { Specifier = II->getName(); SpecifierValid = llvm::StringSwitch(Specifier) .Cases("default", "disable", "error", "once", "suppress", true) .Default(false); // If we read a correct specifier, snatch next token (that should be // ":", checked later). if (SpecifierValid) PP.Lex(Tok); } else { // Token is a numeric constant. It should be either 1, 2, 3 or 4. uint64_t Value; Specifier = PP.getSpelling(Tok, SpecifierBuf); if (PP.parseSimpleIntegerLiteral(Tok, Value)) { SpecifierValid = (Value >= 1) && (Value <= 4); } else SpecifierValid = false; // Next token already snatched by parseSimpleIntegerLiteral. } if (!SpecifierValid) { PP.Diag(Tok, diag::warn_pragma_warning_spec_invalid); return; } if (Tok.isNot(tok::colon)) { PP.Diag(Tok, diag::warn_pragma_warning_expected) << ":"; return; } // Collect the warning ids. SmallVector Ids; PP.Lex(Tok); while (Tok.is(tok::numeric_constant)) { uint64_t Value; if (!PP.parseSimpleIntegerLiteral(Tok, Value) || Value == 0 || Value > std::numeric_limits::max()) { PP.Diag(Tok, diag::warn_pragma_warning_expected_number); return; } Ids.push_back(int(Value)); } if (Callbacks) Callbacks->PragmaWarning(DiagLoc, Specifier, Ids); // Parse the next specifier if there is a semicolon. if (Tok.isNot(tok::semi)) break; PP.Lex(Tok); } } if (Tok.isNot(tok::r_paren)) { PP.Diag(Tok, diag::warn_pragma_warning_expected) << ")"; return; } PP.Lex(Tok); if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma warning"; } }; /// "\#pragma execution_character_set(...)". MSVC supports this pragma only /// for "UTF-8". We parse it and ignore it if UTF-8 is provided and warn /// otherwise to avoid -Wunknown-pragma warnings. struct PragmaExecCharsetHandler : public PragmaHandler { PragmaExecCharsetHandler() : PragmaHandler("execution_character_set") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { // Parse things like: // execution_character_set(push, "UTF-8") // execution_character_set(pop) SourceLocation DiagLoc = Tok.getLocation(); PPCallbacks *Callbacks = PP.getPPCallbacks(); PP.Lex(Tok); if (Tok.isNot(tok::l_paren)) { PP.Diag(Tok, diag::warn_pragma_exec_charset_expected) << "("; return; } PP.Lex(Tok); IdentifierInfo *II = Tok.getIdentifierInfo(); if (II && II->isStr("push")) { // #pragma execution_character_set( push[ , string ] ) PP.Lex(Tok); if (Tok.is(tok::comma)) { PP.Lex(Tok); std::string ExecCharset; if (!PP.FinishLexStringLiteral(Tok, ExecCharset, "pragma execution_character_set", /*AllowMacroExpansion=*/false)) return; // MSVC supports either of these, but nothing else. if (ExecCharset != "UTF-8" && ExecCharset != "utf-8") { PP.Diag(Tok, diag::warn_pragma_exec_charset_push_invalid) << ExecCharset; return; } } if (Callbacks) Callbacks->PragmaExecCharsetPush(DiagLoc, "UTF-8"); } else if (II && II->isStr("pop")) { // #pragma execution_character_set( pop ) PP.Lex(Tok); if (Callbacks) Callbacks->PragmaExecCharsetPop(DiagLoc); } else { PP.Diag(Tok, diag::warn_pragma_exec_charset_spec_invalid); return; } if (Tok.isNot(tok::r_paren)) { PP.Diag(Tok, diag::warn_pragma_exec_charset_expected) << ")"; return; } PP.Lex(Tok); if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma execution_character_set"; } }; /// PragmaIncludeAliasHandler - "\#pragma include_alias("...")". struct PragmaIncludeAliasHandler : public PragmaHandler { PragmaIncludeAliasHandler() : PragmaHandler("include_alias") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &IncludeAliasTok) override { PP.HandlePragmaIncludeAlias(IncludeAliasTok); } }; /// PragmaMessageHandler - Handle the microsoft and gcc \#pragma message /// extension. The syntax is: /// \code /// #pragma message(string) /// \endcode /// OR, in GCC mode: /// \code /// #pragma message string /// \endcode /// string is a string, which is fully macro expanded, and permits string /// concatenation, embedded escape characters, etc... See MSDN for more details. /// Also handles \#pragma GCC warning and \#pragma GCC error which take the same /// form as \#pragma message. struct PragmaMessageHandler : public PragmaHandler { private: const PPCallbacks::PragmaMessageKind Kind; const StringRef Namespace; static const char* PragmaKind(PPCallbacks::PragmaMessageKind Kind, bool PragmaNameOnly = false) { switch (Kind) { case PPCallbacks::PMK_Message: return PragmaNameOnly ? "message" : "pragma message"; case PPCallbacks::PMK_Warning: return PragmaNameOnly ? "warning" : "pragma warning"; case PPCallbacks::PMK_Error: return PragmaNameOnly ? "error" : "pragma error"; } llvm_unreachable("Unknown PragmaMessageKind!"); } public: PragmaMessageHandler(PPCallbacks::PragmaMessageKind Kind, StringRef Namespace = StringRef()) : PragmaHandler(PragmaKind(Kind, true)), Kind(Kind), Namespace(Namespace) {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { SourceLocation MessageLoc = Tok.getLocation(); PP.Lex(Tok); bool ExpectClosingParen = false; switch (Tok.getKind()) { case tok::l_paren: // We have a MSVC style pragma message. ExpectClosingParen = true; // Read the string. PP.Lex(Tok); break; case tok::string_literal: // We have a GCC style pragma message, and we just read the string. break; default: PP.Diag(MessageLoc, diag::err_pragma_message_malformed) << Kind; return; } std::string MessageString; if (!PP.FinishLexStringLiteral(Tok, MessageString, PragmaKind(Kind), /*AllowMacroExpansion=*/true)) return; if (ExpectClosingParen) { if (Tok.isNot(tok::r_paren)) { PP.Diag(Tok.getLocation(), diag::err_pragma_message_malformed) << Kind; return; } PP.Lex(Tok); // eat the r_paren. } if (Tok.isNot(tok::eod)) { PP.Diag(Tok.getLocation(), diag::err_pragma_message_malformed) << Kind; return; } // Output the message. PP.Diag(MessageLoc, (Kind == PPCallbacks::PMK_Error) ? diag::err_pragma_message : diag::warn_pragma_message) << MessageString; // If the pragma is lexically sound, notify any interested PPCallbacks. if (PPCallbacks *Callbacks = PP.getPPCallbacks()) Callbacks->PragmaMessage(MessageLoc, Namespace, Kind, MessageString); } }; /// Handle the clang \#pragma module import extension. The syntax is: /// \code /// #pragma clang module import some.module.name /// \endcode struct PragmaModuleImportHandler : public PragmaHandler { PragmaModuleImportHandler() : PragmaHandler("import") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { SourceLocation ImportLoc = Tok.getLocation(); // Read the module name. llvm::SmallVector, 8> ModuleName; if (LexModuleName(PP, Tok, ModuleName)) return; if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; // If we have a non-empty module path, load the named module. Module *Imported = PP.getModuleLoader().loadModule(ImportLoc, ModuleName, Module::Hidden, /*IsInclusionDirective=*/false); if (!Imported) return; PP.makeModuleVisible(Imported, ImportLoc); PP.EnterAnnotationToken(SourceRange(ImportLoc, ModuleName.back().second), tok::annot_module_include, Imported); if (auto *CB = PP.getPPCallbacks()) CB->moduleImport(ImportLoc, ModuleName, Imported); } }; /// Handle the clang \#pragma module begin extension. The syntax is: /// \code /// #pragma clang module begin some.module.name /// ... /// #pragma clang module end /// \endcode struct PragmaModuleBeginHandler : public PragmaHandler { PragmaModuleBeginHandler() : PragmaHandler("begin") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { SourceLocation BeginLoc = Tok.getLocation(); // Read the module name. llvm::SmallVector, 8> ModuleName; if (LexModuleName(PP, Tok, ModuleName)) return; if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; // We can only enter submodules of the current module. StringRef Current = PP.getLangOpts().CurrentModule; if (ModuleName.front().first->getName() != Current) { PP.Diag(ModuleName.front().second, diag::err_pp_module_begin_wrong_module) << ModuleName.front().first << (ModuleName.size() > 1) << Current.empty() << Current; return; } // Find the module we're entering. We require that a module map for it // be loaded or implicitly loadable. auto &HSI = PP.getHeaderSearchInfo(); Module *M = HSI.lookupModule(Current); if (!M) { PP.Diag(ModuleName.front().second, diag::err_pp_module_begin_no_module_map) << Current; return; } for (unsigned I = 1; I != ModuleName.size(); ++I) { auto *NewM = M->findOrInferSubmodule(ModuleName[I].first->getName()); if (!NewM) { PP.Diag(ModuleName[I].second, diag::err_pp_module_begin_no_submodule) << M->getFullModuleName() << ModuleName[I].first; return; } M = NewM; } // If the module isn't available, it doesn't make sense to enter it. if (Preprocessor::checkModuleIsAvailable( PP.getLangOpts(), PP.getTargetInfo(), PP.getDiagnostics(), M)) { PP.Diag(BeginLoc, diag::note_pp_module_begin_here) << M->getTopLevelModuleName(); return; } // Enter the scope of the submodule. PP.EnterSubmodule(M, BeginLoc, /*ForPragma*/true); PP.EnterAnnotationToken(SourceRange(BeginLoc, ModuleName.back().second), tok::annot_module_begin, M); } }; /// Handle the clang \#pragma module end extension. struct PragmaModuleEndHandler : public PragmaHandler { PragmaModuleEndHandler() : PragmaHandler("end") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { SourceLocation Loc = Tok.getLocation(); PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; Module *M = PP.LeaveSubmodule(/*ForPragma*/true); if (M) PP.EnterAnnotationToken(SourceRange(Loc), tok::annot_module_end, M); else PP.Diag(Loc, diag::err_pp_module_end_without_module_begin); } }; /// Handle the clang \#pragma module build extension. struct PragmaModuleBuildHandler : public PragmaHandler { PragmaModuleBuildHandler() : PragmaHandler("build") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { PP.HandlePragmaModuleBuild(Tok); } }; /// Handle the clang \#pragma module load extension. struct PragmaModuleLoadHandler : public PragmaHandler { PragmaModuleLoadHandler() : PragmaHandler("load") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &Tok) override { SourceLocation Loc = Tok.getLocation(); // Read the module name. llvm::SmallVector, 8> ModuleName; if (LexModuleName(PP, Tok, ModuleName)) return; if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; // Load the module, don't make it visible. PP.getModuleLoader().loadModule(Loc, ModuleName, Module::Hidden, /*IsInclusionDirective=*/false); } }; /// PragmaPushMacroHandler - "\#pragma push_macro" saves the value of the /// macro on the top of the stack. struct PragmaPushMacroHandler : public PragmaHandler { PragmaPushMacroHandler() : PragmaHandler("push_macro") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &PushMacroTok) override { PP.HandlePragmaPushMacro(PushMacroTok); } }; /// PragmaPopMacroHandler - "\#pragma pop_macro" sets the value of the /// macro to the value on the top of the stack. struct PragmaPopMacroHandler : public PragmaHandler { PragmaPopMacroHandler() : PragmaHandler("pop_macro") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &PopMacroTok) override { PP.HandlePragmaPopMacro(PopMacroTok); } }; /// PragmaARCCFCodeAuditedHandler - /// \#pragma clang arc_cf_code_audited begin/end struct PragmaARCCFCodeAuditedHandler : public PragmaHandler { PragmaARCCFCodeAuditedHandler() : PragmaHandler("arc_cf_code_audited") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &NameTok) override { SourceLocation Loc = NameTok.getLocation(); bool IsBegin; Token Tok; // Lex the 'begin' or 'end'. PP.LexUnexpandedToken(Tok); const IdentifierInfo *BeginEnd = Tok.getIdentifierInfo(); if (BeginEnd && BeginEnd->isStr("begin")) { IsBegin = true; } else if (BeginEnd && BeginEnd->isStr("end")) { IsBegin = false; } else { PP.Diag(Tok.getLocation(), diag::err_pp_arc_cf_code_audited_syntax); return; } // Verify that this is followed by EOD. PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; // The start location of the active audit. SourceLocation BeginLoc = PP.getPragmaARCCFCodeAuditedInfo().second; // The start location we want after processing this. SourceLocation NewLoc; if (IsBegin) { // Complain about attempts to re-enter an audit. if (BeginLoc.isValid()) { PP.Diag(Loc, diag::err_pp_double_begin_of_arc_cf_code_audited); PP.Diag(BeginLoc, diag::note_pragma_entered_here); } NewLoc = Loc; } else { // Complain about attempts to leave an audit that doesn't exist. if (!BeginLoc.isValid()) { PP.Diag(Loc, diag::err_pp_unmatched_end_of_arc_cf_code_audited); return; } NewLoc = SourceLocation(); } PP.setPragmaARCCFCodeAuditedInfo(NameTok.getIdentifierInfo(), NewLoc); } }; /// PragmaAssumeNonNullHandler - /// \#pragma clang assume_nonnull begin/end struct PragmaAssumeNonNullHandler : public PragmaHandler { PragmaAssumeNonNullHandler() : PragmaHandler("assume_nonnull") {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &NameTok) override { SourceLocation Loc = NameTok.getLocation(); bool IsBegin; Token Tok; // Lex the 'begin' or 'end'. PP.LexUnexpandedToken(Tok); const IdentifierInfo *BeginEnd = Tok.getIdentifierInfo(); if (BeginEnd && BeginEnd->isStr("begin")) { IsBegin = true; } else if (BeginEnd && BeginEnd->isStr("end")) { IsBegin = false; } else { PP.Diag(Tok.getLocation(), diag::err_pp_assume_nonnull_syntax); return; } // Verify that this is followed by EOD. PP.LexUnexpandedToken(Tok); if (Tok.isNot(tok::eod)) PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma"; // The start location of the active audit. SourceLocation BeginLoc = PP.getPragmaAssumeNonNullLoc(); // The start location we want after processing this. SourceLocation NewLoc; PPCallbacks *Callbacks = PP.getPPCallbacks(); if (IsBegin) { // Complain about attempts to re-enter an audit. if (BeginLoc.isValid()) { PP.Diag(Loc, diag::err_pp_double_begin_of_assume_nonnull); PP.Diag(BeginLoc, diag::note_pragma_entered_here); } NewLoc = Loc; if (Callbacks) Callbacks->PragmaAssumeNonNullBegin(NewLoc); } else { // Complain about attempts to leave an audit that doesn't exist. if (!BeginLoc.isValid()) { PP.Diag(Loc, diag::err_pp_unmatched_end_of_assume_nonnull); return; } NewLoc = SourceLocation(); if (Callbacks) Callbacks->PragmaAssumeNonNullEnd(NewLoc); } PP.setPragmaAssumeNonNullLoc(NewLoc); } }; /// Handle "\#pragma region [...]" /// /// The syntax is /// \code /// #pragma region [optional name] /// #pragma endregion [optional comment] /// \endcode /// /// \note This is /// editor-only /// pragma, just skipped by compiler. struct PragmaRegionHandler : public PragmaHandler { PragmaRegionHandler(const char *pragma) : PragmaHandler(pragma) {} void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer, Token &NameTok) override { // #pragma region: endregion matches can be verified // __pragma(region): no sense, but ignored by msvc // _Pragma is not valid for MSVC, but there isn't any point // to handle a _Pragma differently. } }; } // namespace /// RegisterBuiltinPragmas - Install the standard preprocessor pragmas: /// \#pragma GCC poison/system_header/dependency and \#pragma once. void Preprocessor::RegisterBuiltinPragmas() { AddPragmaHandler(new PragmaOnceHandler()); AddPragmaHandler(new PragmaMarkHandler()); AddPragmaHandler(new PragmaPushMacroHandler()); AddPragmaHandler(new PragmaPopMacroHandler()); AddPragmaHandler(new PragmaMessageHandler(PPCallbacks::PMK_Message)); // #pragma GCC ... AddPragmaHandler("GCC", new PragmaPoisonHandler()); AddPragmaHandler("GCC", new PragmaSystemHeaderHandler()); AddPragmaHandler("GCC", new PragmaDependencyHandler()); AddPragmaHandler("GCC", new PragmaDiagnosticHandler("GCC")); AddPragmaHandler("GCC", new PragmaMessageHandler(PPCallbacks::PMK_Warning, "GCC")); AddPragmaHandler("GCC", new PragmaMessageHandler(PPCallbacks::PMK_Error, "GCC")); // #pragma clang ... AddPragmaHandler("clang", new PragmaPoisonHandler()); AddPragmaHandler("clang", new PragmaSystemHeaderHandler()); AddPragmaHandler("clang", new PragmaDebugHandler()); AddPragmaHandler("clang", new PragmaDependencyHandler()); AddPragmaHandler("clang", new PragmaDiagnosticHandler("clang")); AddPragmaHandler("clang", new PragmaARCCFCodeAuditedHandler()); AddPragmaHandler("clang", new PragmaAssumeNonNullHandler()); // #pragma clang module ... auto *ModuleHandler = new PragmaNamespace("module"); AddPragmaHandler("clang", ModuleHandler); ModuleHandler->AddPragma(new PragmaModuleImportHandler()); ModuleHandler->AddPragma(new PragmaModuleBeginHandler()); ModuleHandler->AddPragma(new PragmaModuleEndHandler()); ModuleHandler->AddPragma(new PragmaModuleBuildHandler()); ModuleHandler->AddPragma(new PragmaModuleLoadHandler()); // Add region pragmas. AddPragmaHandler(new PragmaRegionHandler("region")); AddPragmaHandler(new PragmaRegionHandler("endregion")); // MS extensions. if (LangOpts.MicrosoftExt) { AddPragmaHandler(new PragmaWarningHandler()); AddPragmaHandler(new PragmaExecCharsetHandler()); AddPragmaHandler(new PragmaIncludeAliasHandler()); AddPragmaHandler(new PragmaHdrstopHandler()); } // Pragmas added by plugins for (const PragmaHandlerRegistry::entry &handler : PragmaHandlerRegistry::entries()) { AddPragmaHandler(handler.instantiate().release()); } } /// Ignore all pragmas, useful for modes such as -Eonly which would otherwise /// warn about those pragmas being unknown. void Preprocessor::IgnorePragmas() { AddPragmaHandler(new EmptyPragmaHandler()); // Also ignore all pragmas in all namespaces created // in Preprocessor::RegisterBuiltinPragmas(). AddPragmaHandler("GCC", new EmptyPragmaHandler()); AddPragmaHandler("clang", new EmptyPragmaHandler()); }