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Diffstat (limited to 'clang/lib/Lex/PPDirectives.cpp')
-rw-r--r-- | clang/lib/Lex/PPDirectives.cpp | 1153 |
1 files changed, 1153 insertions, 0 deletions
diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp new file mode 100644 index 00000000000..b24f5b63760 --- /dev/null +++ b/clang/lib/Lex/PPDirectives.cpp @@ -0,0 +1,1153 @@ +//===--- 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. +// +//===----------------------------------------------------------------------===// +// +// This file implements # directive processing for the Preprocessor. +// +//===----------------------------------------------------------------------===// + +#include "clang/Lex/Preprocessor.h" +#include "clang/Lex/HeaderSearch.h" +#include "clang/Lex/MacroInfo.h" +#include "clang/Lex/PPCallbacks.h" +#include "clang/Basic/Diagnostic.h" +#include "clang/Basic/SourceManager.h" +using namespace clang; + +//===----------------------------------------------------------------------===// +// Utility Methods for Preprocessor Directive Handling. +//===----------------------------------------------------------------------===// + +/// DiscardUntilEndOfDirective - Read and discard all tokens remaining on the +/// current line until the tok::eom token is found. +void Preprocessor::DiscardUntilEndOfDirective() { + Token Tmp; + do { + LexUnexpandedToken(Tmp); + } while (Tmp.isNot(tok::eom)); +} + +/// isCXXNamedOperator - Returns "true" if the token is a named operator in C++. +static bool isCXXNamedOperator(const std::string &Spelling) { + return Spelling == "and" || Spelling == "bitand" || Spelling == "bitor" || + Spelling == "compl" || Spelling == "not" || Spelling == "not_eq" || + Spelling == "or" || Spelling == "xor"; +} + +/// ReadMacroName - Lex and validate a macro name, which occurs after a +/// #define or #undef. This sets the token kind to eom and discards the rest +/// of the macro line if the macro name is invalid. 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); + + // Missing macro name? + if (MacroNameTok.is(tok::eom)) + return Diag(MacroNameTok, diag::err_pp_missing_macro_name); + + IdentifierInfo *II = MacroNameTok.getIdentifierInfo(); + if (II == 0) { + std::string Spelling = getSpelling(MacroNameTok); + if (isCXXNamedOperator(Spelling)) + // C++ 2.5p2: Alternative tokens behave the same as its primary token + // except for their spellings. + Diag(MacroNameTok, diag::err_pp_operator_used_as_macro_name, Spelling); + else + Diag(MacroNameTok, diag::err_pp_macro_not_identifier); + // Fall through on error. + } else if (isDefineUndef && II->getPPKeywordID() == tok::pp_defined) { + // Error if defining "defined": C99 6.10.8.4. + Diag(MacroNameTok, diag::err_defined_macro_name); + } else if (isDefineUndef && II->hasMacroDefinition() && + getMacroInfo(II)->isBuiltinMacro()) { + // Error if defining "__LINE__" and other builtins: C99 6.10.8.4. + if (isDefineUndef == 1) + Diag(MacroNameTok, diag::pp_redef_builtin_macro); + else + Diag(MacroNameTok, diag::pp_undef_builtin_macro); + } else { + // Okay, we got a good identifier node. Return it. + return; + } + + // Invalid macro name, read and discard the rest of the line. Then set the + // token kind to tok::eom. + MacroNameTok.setKind(tok::eom); + return DiscardUntilEndOfDirective(); +} + +/// CheckEndOfDirective - Ensure that the next token is a tok::eom token. If +/// not, emit a diagnostic and consume up until the eom. +void Preprocessor::CheckEndOfDirective(const char *DirType) { + Token Tmp; + // Lex unexpanded tokens: macros might expand to zero tokens, causing us to + // miss diagnosing invalid lines. + 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::eom)) { + Diag(Tmp, diag::ext_pp_extra_tokens_at_eol, DirType); + 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) { + ++NumSkipped; + assert(CurTokenLexer == 0 && CurLexer && + "Lexing a macro, not a file?"); + + CurLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false, + FoundNonSkipPortion, FoundElse); + + // Enter raw mode to disable identifier lookup (and thus macro expansion), + // disabling warnings, etc. + CurLexer->LexingRawMode = true; + Token Tok; + while (1) { + CurLexer->Lex(Tok); + + // 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 (!CurLexer->ConditionalStack.empty()) { + Diag(CurLexer->ConditionalStack.back().IfLoc, + diag::err_pp_unterminated_conditional); + CurLexer->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 EOM token (this terminates the macro). + CurLexer->ParsingPreprocessorDirective = true; + CurLexer->KeepCommentMode = 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::identifier)) { + CurLexer->ParsingPreprocessorDirective = false; + // Restore comment saving mode. + CurLexer->KeepCommentMode = KeepComments; + 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. + const char *RawCharData = SourceMgr.getCharacterData(Tok.getLocation()); + char FirstChar = RawCharData[0]; + if (FirstChar >= 'a' && FirstChar <= 'z' && + FirstChar != 'i' && FirstChar != 'e') { + CurLexer->ParsingPreprocessorDirective = false; + // Restore comment saving mode. + CurLexer->KeepCommentMode = KeepComments; + 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. + // TODO: could do this with zero copies in the no-clean case by using + // strncmp below. + char Directive[20]; + unsigned IdLen; + if (!Tok.needsCleaning() && Tok.getLength() < 20) { + IdLen = Tok.getLength(); + memcpy(Directive, RawCharData, IdLen); + Directive[IdLen] = 0; + } else { + std::string DirectiveStr = getSpelling(Tok); + IdLen = DirectiveStr.size(); + if (IdLen >= 20) { + CurLexer->ParsingPreprocessorDirective = false; + // Restore comment saving mode. + CurLexer->KeepCommentMode = KeepComments; + continue; + } + memcpy(Directive, &DirectiveStr[0], IdLen); + Directive[IdLen] = 0; + } + + if (FirstChar == 'i' && Directive[1] == 'f') { + if ((IdLen == 2) || // "if" + (IdLen == 5 && !strcmp(Directive+2, "def")) || // "ifdef" + (IdLen == 6 && !strcmp(Directive+2, "ndef"))) { // "ifndef" + // We know the entire #if/#ifdef/#ifndef block will be skipped, don't + // bother parsing the condition. + DiscardUntilEndOfDirective(); + CurLexer->pushConditionalLevel(Tok.getLocation(), /*wasskipping*/true, + /*foundnonskip*/false, + /*fnddelse*/false); + } + } else if (FirstChar == 'e') { + if (IdLen == 5 && !strcmp(Directive+1, "ndif")) { // "endif" + CheckEndOfDirective("#endif"); + PPConditionalInfo CondInfo; + CondInfo.WasSkipping = true; // Silence bogus warning. + bool InCond = CurLexer->popConditionalLevel(CondInfo); + InCond = 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) + break; + } else if (IdLen == 4 && !strcmp(Directive+1, "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. + CheckEndOfDirective("#else"); + PPConditionalInfo &CondInfo = CurLexer->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; + break; + } + } else if (IdLen == 4 && !strcmp(Directive+1, "lif")) { // "elif". + PPConditionalInfo &CondInfo = CurLexer->peekConditionalLevel(); + + bool ShouldEnter; + // 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(); + ShouldEnter = false; + } else { + // Restore the value of LexingRawMode so that identifiers are + // looked up, etc, inside the #elif expression. + assert(CurLexer->LexingRawMode && "We have to be skipping here!"); + CurLexer->LexingRawMode = false; + IdentifierInfo *IfNDefMacro = 0; + ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro); + CurLexer->LexingRawMode = true; + } + + // 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 condition is true, enter it! + if (ShouldEnter) { + CondInfo.FoundNonSkip = true; + break; + } + } + } + + CurLexer->ParsingPreprocessorDirective = false; + // Restore comment saving mode. + CurLexer->KeepCommentMode = KeepComments; + } + + // 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. + CurLexer->LexingRawMode = false; +} + +/// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, +/// return null on failure. isAngled indicates whether the file reference is +/// for system #include's or not (i.e. using <> instead of ""). +const FileEntry *Preprocessor::LookupFile(const char *FilenameStart, + const char *FilenameEnd, + bool isAngled, + const DirectoryLookup *FromDir, + const DirectoryLookup *&CurDir) { + // If the header lookup mechanism may be relative to the current file, pass in + // info about where the current file is. + const FileEntry *CurFileEnt = 0; + if (!FromDir) { + SourceLocation FileLoc = getCurrentFileLexer()->getFileLoc(); + CurFileEnt = SourceMgr.getFileEntryForLoc(FileLoc); + } + + // Do a standard file entry lookup. + CurDir = CurDirLookup; + const FileEntry *FE = + HeaderInfo.LookupFile(FilenameStart, FilenameEnd, + isAngled, FromDir, CurDir, CurFileEnt); + if (FE) return FE; + + // 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 (CurLexer && !CurLexer->Is_PragmaLexer) { + if ((CurFileEnt = SourceMgr.getFileEntryForLoc(CurLexer->getFileLoc()))) + if ((FE = HeaderInfo.LookupSubframeworkHeader(FilenameStart, FilenameEnd, + CurFileEnt))) + return FE; + } + + for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) { + IncludeStackInfo &ISEntry = IncludeMacroStack[e-i-1]; + if (ISEntry.TheLexer && !ISEntry.TheLexer->Is_PragmaLexer) { + if ((CurFileEnt = + SourceMgr.getFileEntryForLoc(ISEntry.TheLexer->getFileLoc()))) + if ((FE = HeaderInfo.LookupSubframeworkHeader(FilenameStart, + FilenameEnd, CurFileEnt))) + return FE; + } + } + + // Otherwise, we really couldn't find the file. + return 0; +} + + +//===----------------------------------------------------------------------===// +// Preprocessor Directive Handling. +//===----------------------------------------------------------------------===// + +/// 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 + // EOM token (which terminates the directive). + CurLexer->ParsingPreprocessorDirective = true; + + ++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 = CurLexer->MIOpt.getHasReadAnyTokensVal(); + + // 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 non-portable behavior, emit a diagnostic. + if (InMacroArgs) + Diag(Result, diag::ext_embedded_directive); + +TryAgain: + switch (Result.getKind()) { + case tok::eom: + return; // null directive. + case tok::comment: + // Handle stuff like "# /*foo*/ define X" in -E -C mode. + LexUnexpandedToken(Result); + goto TryAgain; + + case tok::numeric_constant: + // FIXME: implement # 7 line numbers! + DiscardUntilEndOfDirective(); + return; + default: + IdentifierInfo *II = Result.getIdentifierInfo(); + if (II == 0) 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: + return HandleIncludeDirective(Result); // Handle #include. + + // C99 6.10.3 - Macro Replacement. + case tok::pp_define: + return HandleDefineDirective(Result); + case tok::pp_undef: + return HandleUndefDirective(Result); + + // C99 6.10.4 - Line Control. + case tok::pp_line: + // FIXME: implement #line + DiscardUntilEndOfDirective(); + return; + + // 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(); + + // GNU Extensions. + case tok::pp_import: + return HandleImportDirective(Result); + case tok::pp_include_next: + return HandleIncludeNextDirective(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; + } + break; + } + + // 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. +} + +void Preprocessor::HandleUserDiagnosticDirective(Token &Tok, + bool isWarning) { + // 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. + std::string Message = CurLexer->ReadToEndOfLine(); + + unsigned DiagID = isWarning ? diag::pp_hash_warning : diag::err_pp_hash_error; + return Diag(Tok, DiagID, Message); +} + +/// 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)) + return Diag(StrTok, diag::err_pp_malformed_ident); + + // Verify that there is nothing after the string, other than EOM. + CheckEndOfDirective("#ident"); + + if (Callbacks) + Callbacks->Ident(Tok.getLocation(), getSpelling(StrTok)); +} + +//===----------------------------------------------------------------------===// +// 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, + const char *&BufStart, + const char *&BufEnd) { + // Get the text form of the filename. + assert(BufStart != BufEnd && "Can't have tokens with empty spellings!"); + + // Make sure the filename is <x> or "x". + bool isAngled; + if (BufStart[0] == '<') { + if (BufEnd[-1] != '>') { + Diag(Loc, diag::err_pp_expects_filename); + BufStart = 0; + return true; + } + isAngled = true; + } else if (BufStart[0] == '"') { + if (BufEnd[-1] != '"') { + Diag(Loc, diag::err_pp_expects_filename); + BufStart = 0; + return true; + } + isAngled = false; + } else { + Diag(Loc, diag::err_pp_expects_filename); + BufStart = 0; + return true; + } + + // Diagnose #include "" as invalid. + if (BufEnd-BufStart <= 2) { + Diag(Loc, diag::err_pp_empty_filename); + BufStart = 0; + return ""; + } + + // Skip the brackets. + ++BufStart; + --BufEnd; + return isAngled; +} + +/// ConcatenateIncludeName - 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: +/// #define FOO <a/b.h> +/// #include FOO +/// because in this case, "<a/b.h>" 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 EOM marker. +static bool ConcatenateIncludeName(llvm::SmallVector<char, 128> &FilenameBuffer, + Preprocessor &PP) { + Token CurTok; + + PP.Lex(CurTok); + while (CurTok.isNot(tok::eom)) { + // 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 = PP.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; + + PP.Lex(CurTok); + } + + // If we hit the eom marker, emit an error and return true so that the caller + // knows the EOM has been read. + PP.Diag(CurTok.getLocation(), diag::err_pp_expects_filename); + return 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. +void Preprocessor::HandleIncludeDirective(Token &IncludeTok, + const DirectoryLookup *LookupFrom, + bool isImport) { + + Token FilenameTok; + CurLexer->LexIncludeFilename(FilenameTok); + + // Reserve a buffer to get the spelling. + llvm::SmallVector<char, 128> FilenameBuffer; + const char *FilenameStart, *FilenameEnd; + + switch (FilenameTok.getKind()) { + case tok::eom: + // If the token kind is EOM, the error has already been diagnosed. + return; + + case tok::angle_string_literal: + case tok::string_literal: { + FilenameBuffer.resize(FilenameTok.getLength()); + FilenameStart = &FilenameBuffer[0]; + unsigned Len = getSpelling(FilenameTok, FilenameStart); + FilenameEnd = FilenameStart+Len; + break; + } + + case tok::less: + // This could be a <foo/bar.h> file coming from a macro expansion. In this + // case, glue the tokens together into FilenameBuffer and interpret those. + FilenameBuffer.push_back('<'); + if (ConcatenateIncludeName(FilenameBuffer, *this)) + return; // Found <eom> but no ">"? Diagnostic already emitted. + FilenameStart = &FilenameBuffer[0]; + FilenameEnd = &FilenameBuffer[FilenameBuffer.size()]; + break; + default: + Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename); + DiscardUntilEndOfDirective(); + return; + } + + bool isAngled = GetIncludeFilenameSpelling(FilenameTok.getLocation(), + FilenameStart, FilenameEnd); + // If GetIncludeFilenameSpelling set the start ptr to null, there was an + // error. + if (FilenameStart == 0) { + DiscardUntilEndOfDirective(); + return; + } + + // Verify that there is nothing after the filename, other than EOM. Use the + // preprocessor to lex this in case lexing the filename entered a macro. + CheckEndOfDirective("#include"); + + // Check that we don't have infinite #include recursion. + if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1) + return Diag(FilenameTok, diag::err_pp_include_too_deep); + + // Search include directories. + const DirectoryLookup *CurDir; + const FileEntry *File = LookupFile(FilenameStart, FilenameEnd, + isAngled, LookupFrom, CurDir); + if (File == 0) + return Diag(FilenameTok, diag::err_pp_file_not_found, + std::string(FilenameStart, FilenameEnd)); + + // Ask HeaderInfo if we should enter this #include file. + if (!HeaderInfo.ShouldEnterIncludeFile(File, isImport)) { + // If it returns true, #including this file will have no effect. + return; + } + + // Look up the file, create a File ID for it. + unsigned FileID = SourceMgr.createFileID(File, FilenameTok.getLocation()); + if (FileID == 0) + return Diag(FilenameTok, diag::err_pp_file_not_found, + std::string(FilenameStart, FilenameEnd)); + + // Finally, if all is good, enter the new file! + EnterSourceFile(FileID, CurDir); +} + +/// HandleIncludeNextDirective - Implements #include_next. +/// +void Preprocessor::HandleIncludeNextDirective(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 = 0; + Diag(IncludeNextTok, diag::pp_include_next_in_primary); + } else if (Lookup == 0) { + Diag(IncludeNextTok, diag::pp_include_next_absolute_path); + } else { + // Start looking up in the next directory. + ++Lookup; + } + + return HandleIncludeDirective(IncludeNextTok, Lookup); +} + +/// HandleImportDirective - Implements #import. +/// +void Preprocessor::HandleImportDirective(Token &ImportTok) { + Diag(ImportTok, diag::ext_pp_import_directive); + + return HandleIncludeDirective(ImportTok, 0, true); +} + +//===----------------------------------------------------------------------===// +// 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) { + llvm::SmallVector<IdentifierInfo*, 32> Arguments; + + Token Tok; + while (1) { + LexUnexpandedToken(Tok); + switch (Tok.getKind()) { + case tok::r_paren: + // Found the end of the argument list. + if (Arguments.empty()) { // #define FOO() + MI->setArgumentList(Arguments.begin(), Arguments.end()); + 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 + // Warn if use of C99 feature in non-C99 mode. + if (!Features.C99) Diag(Tok, diag::ext_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; + } + // Add the __VA_ARGS__ identifier as an argument. + Arguments.push_back(Ident__VA_ARGS__); + MI->setIsC99Varargs(); + MI->setArgumentList(Arguments.begin(), Arguments.end()); + return false; + case tok::eom: // #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 == 0) { + // #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->getName()); + 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.begin(), Arguments.end()); + 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.begin(), Arguments.end()); + 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) { + ++NumDefined; + + Token MacroNameTok; + ReadMacroName(MacroNameTok, 1); + + // Error reading macro name? If so, diagnostic already issued. + if (MacroNameTok.is(tok::eom)) + return; + + // If we are supposed to keep comments in #defines, reenable comment saving + // mode. + CurLexer->KeepCommentMode = KeepMacroComments; + + // Create the new macro. + MacroInfo *MI = new MacroInfo(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::eom)) { + // If there is no body to this macro, we have no special handling here. + } else if (Tok.is(tok::l_paren) && !Tok.hasLeadingSpace()) { + // This is a function-like macro definition. Read the argument list. + MI->setIsFunctionLike(); + if (ReadMacroDefinitionArgList(MI)) { + // Forget about MI. + delete MI; + // Throw away the rest of the line. + if (CurLexer->ParsingPreprocessorDirective) + DiscardUntilEndOfDirective(); + return; + } + + // Read the first token after the arg list for down below. + LexUnexpandedToken(Tok); + } else if (!Tok.hasLeadingSpace()) { + // C99 requires whitespace between the macro definition and the body. Emit + // a diagnostic for something like "#define X+". + if (Features.C99) { + Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name); + } else { + // FIXME: C90/C++ do not get this diagnostic, but it does get a similar + // one in some cases! + } + } else { + // 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); + } + + // 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 rest of the macro body. + if (MI->isObjectLike()) { + // Object-like macros are very simple, just read their body. + while (Tok.isNot(tok::eom)) { + MI->AddTokenToBody(Tok); + // Get the next token of the macro. + LexUnexpandedToken(Tok); + } + + } else { + // Otherwise, read the body of a function-like macro. This has to validate + // the # (stringize) operator. + while (Tok.isNot(tok::eom)) { + MI->AddTokenToBody(Tok); + + // Check C99 6.10.3.2p1: ensure that # operators are followed by macro + // parameters in function-like macro expansions. + if (Tok.isNot(tok::hash)) { + // Get the next token of the macro. + LexUnexpandedToken(Tok); + continue; + } + + // Get the next token of the macro. + LexUnexpandedToken(Tok); + + // Not a macro arg identifier? + if (!Tok.getIdentifierInfo() || + MI->getArgumentNum(Tok.getIdentifierInfo()) == -1) { + Diag(Tok, diag::err_pp_stringize_not_parameter); + delete MI; + + // Disable __VA_ARGS__ again. + Ident__VA_ARGS__->setIsPoisoned(true); + return; + } + + // Things look ok, add the param name token to the macro. + MI->AddTokenToBody(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 begining 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); + delete MI; + return; + } + if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) { + Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end); + delete MI; + return; + } + } + + // If this is the primary source file, remember that this macro hasn't been + // used yet. + if (isInPrimaryFile()) + MI->setIsUsed(false); + + // Finally, if this identifier already had a macro defined for it, verify that + // the macro bodies are identical and free the old definition. + if (MacroInfo *OtherMI = getMacroInfo(MacroNameTok.getIdentifierInfo())) { + if (!OtherMI->isUsed()) + Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used); + + // Macros must be identical. This means all tokes and whitespace separation + // must be the same. C99 6.10.3.2. + if (!MI->isIdenticalTo(*OtherMI, *this)) { + Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef, + MacroNameTok.getIdentifierInfo()->getName()); + Diag(OtherMI->getDefinitionLoc(), diag::ext_pp_macro_redef2); + } + delete OtherMI; + } + + setMacroInfo(MacroNameTok.getIdentifierInfo(), MI); +} + +/// 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::eom)) + 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. + MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo()); + + // If the macro is not defined, this is a noop undef, just return. + if (MI == 0) return; + + if (!MI->isUsed()) + Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used); + + // Free macro definition. + delete MI; + setMacroInfo(MacroNameTok.getIdentifierInfo(), 0); +} + + +//===----------------------------------------------------------------------===// +// 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::eom)) { + // 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"); + + if (CurLexer->getConditionalStackDepth() == 0) { + // If the start of a top-level #ifdef, inform MIOpt. + if (!ReadAnyTokensBeforeDirective) { + assert(isIfndef && "#ifdef shouldn't reach here"); + CurLexer->MIOpt.EnterTopLevelIFNDEF(MacroNameTok.getIdentifierInfo()); + } else + CurLexer->MIOpt.EnterTopLevelConditional(); + } + + IdentifierInfo *MII = MacroNameTok.getIdentifierInfo(); + MacroInfo *MI = getMacroInfo(MII); + + // If there is a macro, process it. + if (MI) // Mark it used. + MI->setIsUsed(true); + + // 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. + CurLexer->pushConditionalLevel(DirectiveTok.getLocation(), /*wasskip*/false, + /*foundnonskip*/true, /*foundelse*/false); + } else { + // No, skip the contents of this block and return the first token after it. + SkipExcludedConditionalBlock(DirectiveTok.getLocation(), + /*Foundnonskip*/false, + /*FoundElse*/false); + } +} + +/// HandleIfDirective - Implements the #if directive. +/// +void Preprocessor::HandleIfDirective(Token &IfToken, + bool ReadAnyTokensBeforeDirective) { + ++NumIf; + + // Parse and evaluation the conditional expression. + IdentifierInfo *IfNDefMacro = 0; + bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro); + + // Should we include the stuff contained by this directive? + if (ConditionalTrue) { + // If this condition is equivalent to #ifndef X, and if this is the first + // directive seen, handle it for the multiple-include optimization. + if (CurLexer->getConditionalStackDepth() == 0) { + if (!ReadAnyTokensBeforeDirective && IfNDefMacro) + CurLexer->MIOpt.EnterTopLevelIFNDEF(IfNDefMacro); + else + CurLexer->MIOpt.EnterTopLevelConditional(); + } + + // Yes, remember that we are inside a conditional, then lex the next token. + CurLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false, + /*foundnonskip*/true, /*foundelse*/false); + } else { + // No, skip the contents of this block and return the first token after it. + 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 (CurLexer->popConditionalLevel(CondInfo)) { + // No conditionals on the stack: this is an #endif without an #if. + return Diag(EndifToken, diag::err_pp_endif_without_if); + } + + // If this the end of a top-level #endif, inform MIOpt. + if (CurLexer->getConditionalStackDepth() == 0) + CurLexer->MIOpt.ExitTopLevelConditional(); + + assert(!CondInfo.WasSkipping && !CurLexer->LexingRawMode && + "This code should only be reachable in the non-skipping case!"); +} + + +void Preprocessor::HandleElseDirective(Token &Result) { + ++NumElse; + + // #else directive in a non-skipping conditional... start skipping. + CheckEndOfDirective("#else"); + + PPConditionalInfo CI; + if (CurLexer->popConditionalLevel(CI)) + return Diag(Result, diag::pp_err_else_without_if); + + // If this is a top-level #else, inform the MIOpt. + if (CurLexer->getConditionalStackDepth() == 0) + CurLexer->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); + + // Finally, skip the rest of the contents of this block and return the first + // token after it. + return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, + /*FoundElse*/true); +} + +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). + DiscardUntilEndOfDirective(); + + PPConditionalInfo CI; + if (CurLexer->popConditionalLevel(CI)) + return Diag(ElifToken, diag::pp_err_elif_without_if); + + // If this is a top-level #elif, inform the MIOpt. + if (CurLexer->getConditionalStackDepth() == 0) + CurLexer->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); + + // Finally, skip the rest of the contents of this block and return the first + // token after it. + return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true, + /*FoundElse*/CI.FoundElse); +} + |