Nigel
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
llvm-project/clang/lib/Lex/PPDirectives.cpp

2517 lines
91 KiB
C++
Raw Blame History

//===--- PPDirectives.cpp - Directive Handling for Preprocessor -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief Implements # directive processing for the Preprocessor.
///
//===----------------------------------------------------------------------===//
#include "clang/Lex/Preprocessor.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Lex/CodeCompletionHandler.h"
#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/HeaderSearchOptions.h"
#include "clang/Lex/LexDiagnostic.h"
#include "clang/Lex/LiteralSupport.h"
#include "clang/Lex/MacroInfo.h"
#include "clang/Lex/ModuleLoader.h"
#include "clang/Lex/Pragma.h"
#include "llvm/ADT/APInt.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/SaveAndRestore.h"
using namespace clang;
//===----------------------------------------------------------------------===//
// Utility Methods for Preprocessor Directive Handling.
//===----------------------------------------------------------------------===//
MacroInfo *Preprocessor::AllocateMacroInfo() {
MacroInfoChain *MIChain = BP.Allocate<MacroInfoChain>();
MIChain->Next = MIChainHead;
MIChainHead = MIChain;
return &MIChain->MI;
}
MacroInfo *Preprocessor::AllocateMacroInfo(SourceLocation L) {
MacroInfo *MI = AllocateMacroInfo();
new (MI) MacroInfo(L);
return MI;
}
MacroInfo *Preprocessor::AllocateDeserializedMacroInfo(SourceLocation L,
unsigned SubModuleID) {
static_assert(llvm::AlignOf<MacroInfo>::Alignment >= sizeof(SubModuleID),
"alignment for MacroInfo is less than the ID");
DeserializedMacroInfoChain *MIChain =
BP.Allocate<DeserializedMacroInfoChain>();
MIChain->Next = DeserialMIChainHead;
DeserialMIChainHead = MIChain;
MacroInfo *MI = &MIChain->MI;
new (MI) MacroInfo(L);
MI->FromASTFile = true;
MI->setOwningModuleID(SubModuleID);
return MI;
}
DefMacroDirective *Preprocessor::AllocateDefMacroDirective(MacroInfo *MI,
SourceLocation Loc) {
return new (BP) DefMacroDirective(MI, Loc);
}
UndefMacroDirective *
Preprocessor::AllocateUndefMacroDirective(SourceLocation UndefLoc) {
return new (BP) UndefMacroDirective(UndefLoc);
}
VisibilityMacroDirective *
Preprocessor::AllocateVisibilityMacroDirective(SourceLocation Loc,
bool isPublic) {
return new (BP) VisibilityMacroDirective(Loc, isPublic);
}
/// \brief Read and discard all tokens remaining on the current line until
/// the tok::eod token is found.
void Preprocessor::DiscardUntilEndOfDirective() {
Token Tmp;
do {
LexUnexpandedToken(Tmp);
assert(Tmp.isNot(tok::eof) && "EOF seen while discarding directive tokens");
} while (Tmp.isNot(tok::eod));
}
/// \brief Enumerates possible cases of #define/#undef a reserved identifier.
enum MacroDiag {
MD_NoWarn, //> Not a reserved identifier
MD_KeywordDef, //> Macro hides keyword, enabled by default
MD_ReservedMacro //> #define of #undef reserved id, disabled by default
};
/// \brief Checks if the specified identifier is reserved in the specified
/// language.
/// This function does not check if the identifier is a keyword.
static bool isReservedId(StringRef Text, const LangOptions &Lang) {
// C++ [macro.names], C11 7.1.3:
// All identifiers that begin with an underscore and either an uppercase
// letter or another underscore are always reserved for any use.
if (Text.size() >= 2 && Text[0] == '_' &&
(isUppercase(Text[1]) || Text[1] == '_'))
return true;
// C++ [global.names]
// Each name that contains a double underscore ... is reserved to the
// implementation for any use.
if (Lang.CPlusPlus) {
if (Text.find("__") != StringRef::npos)
return true;
}
return false;
}
static MacroDiag shouldWarnOnMacroDef(Preprocessor &PP, IdentifierInfo *II) {
const LangOptions &Lang = PP.getLangOpts();
StringRef Text = II->getName();
if (isReservedId(Text, Lang))
return MD_ReservedMacro;
if (II->isKeyword(Lang))
return MD_KeywordDef;
if (Lang.CPlusPlus11 && (Text.equals("override") || Text.equals("final")))
return MD_KeywordDef;
return MD_NoWarn;
}
static MacroDiag shouldWarnOnMacroUndef(Preprocessor &PP, IdentifierInfo *II) {
const LangOptions &Lang = PP.getLangOpts();
StringRef Text = II->getName();
// Do not warn on keyword undef. It is generally harmless and widely used.
if (isReservedId(Text, Lang))
return MD_ReservedMacro;
return MD_NoWarn;
}
bool Preprocessor::CheckMacroName(Token &MacroNameTok, MacroUse isDefineUndef,
bool *ShadowFlag) {
// Missing macro name?
if (MacroNameTok.is(tok::eod))
return Diag(MacroNameTok, diag::err_pp_missing_macro_name);
IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
if (!II) {
bool Invalid = false;
std::string Spelling = getSpelling(MacroNameTok, &Invalid);
if (Invalid)
return Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
II = getIdentifierInfo(Spelling);
if (!II->isCPlusPlusOperatorKeyword())
return Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
// C++ 2.5p2: Alternative tokens behave the same as its primary token
// except for their spellings.
Diag(MacroNameTok, getLangOpts().MicrosoftExt
? diag::ext_pp_operator_used_as_macro_name
: diag::err_pp_operator_used_as_macro_name)
<< II << MacroNameTok.getKind();
// Allow #defining |and| and friends for Microsoft compatibility or
// recovery when legacy C headers are included in C++.
MacroNameTok.setIdentifierInfo(II);
}
if ((isDefineUndef != MU_Other) && II->getPPKeywordID() == tok::pp_defined) {
// Error if defining "defined": C99 6.10.8/4, C++ [cpp.predefined]p4.
return Diag(MacroNameTok, diag::err_defined_macro_name);
}
if (isDefineUndef == MU_Undef) {
auto *MI = getMacroInfo(II);
if (MI && MI->isBuiltinMacro()) {
// Warn if undefining "__LINE__" and other builtins, per C99 6.10.8/4
// and C++ [cpp.predefined]p4], but allow it as an extension.
Diag(MacroNameTok, diag::ext_pp_undef_builtin_macro);
}
}
// If defining/undefining reserved identifier or a keyword, we need to issue
// a warning.
SourceLocation MacroNameLoc = MacroNameTok.getLocation();
if (ShadowFlag)
*ShadowFlag = false;
if (!SourceMgr.isInSystemHeader(MacroNameLoc) &&
(strcmp(SourceMgr.getBufferName(MacroNameLoc), "<built-in>") != 0)) {
MacroDiag D = MD_NoWarn;
if (isDefineUndef == MU_Define) {
D = shouldWarnOnMacroDef(*this, II);
}
else if (isDefineUndef == MU_Undef)
D = shouldWarnOnMacroUndef(*this, II);
if (D == MD_KeywordDef) {
// We do not want to warn on some patterns widely used in configuration
// scripts. This requires analyzing next tokens, so do not issue warnings
// now, only inform caller.
if (ShadowFlag)
*ShadowFlag = true;
}
if (D == MD_ReservedMacro)
Diag(MacroNameTok, diag::warn_pp_macro_is_reserved_id);
}
// Okay, we got a good identifier.
return false;
}
/// \brief Lex and validate a macro name, which occurs after a
/// \#define or \#undef.
///
/// This sets the token kind to eod and discards the rest of the macro line if
/// the macro name is invalid.
///
/// \param MacroNameTok Token that is expected to be a macro name.
/// \param isDefineUndef Context in which macro is used.
/// \param ShadowFlag Points to a flag that is set if macro shadows a keyword.
void Preprocessor::ReadMacroName(Token &MacroNameTok, MacroUse isDefineUndef,
bool *ShadowFlag) {
// Read the token, don't allow macro expansion on it.
LexUnexpandedToken(MacroNameTok);
if (MacroNameTok.is(tok::code_completion)) {
if (CodeComplete)
CodeComplete->CodeCompleteMacroName(isDefineUndef == MU_Define);
setCodeCompletionReached();
LexUnexpandedToken(MacroNameTok);
}
if (!CheckMacroName(MacroNameTok, isDefineUndef, ShadowFlag))
return;
// Invalid macro name, read and discard the rest of the line and set the
// token kind to tok::eod if necessary.
if (MacroNameTok.isNot(tok::eod)) {
MacroNameTok.setKind(tok::eod);
DiscardUntilEndOfDirective();
}
}
/// \brief Ensure that the next token is a tok::eod token.
///
/// If not, emit a diagnostic and consume up until the eod. If EnableMacros is
/// true, then we consider macros that expand to zero tokens as being ok.
void Preprocessor::CheckEndOfDirective(const char *DirType, bool EnableMacros) {
Token Tmp;
// Lex unexpanded tokens for most directives: macros might expand to zero
// tokens, causing us to miss diagnosing invalid lines. Some directives (like
// #line) allow empty macros.
if (EnableMacros)
Lex(Tmp);
else
LexUnexpandedToken(Tmp);
// There should be no tokens after the directive, but we allow them as an
// extension.
while (Tmp.is(tok::comment)) // Skip comments in -C mode.
LexUnexpandedToken(Tmp);
if (Tmp.isNot(tok::eod)) {
// Add a fixit in GNU/C99/C++ mode. Don't offer a fixit for strict-C89,
// or if this is a macro-style preprocessing directive, because it is more
// trouble than it is worth to insert /**/ and check that there is no /**/
// in the range also.
FixItHint Hint;
if ((LangOpts.GNUMode || LangOpts.C99 || LangOpts.CPlusPlus) &&
!CurTokenLexer)
Hint = FixItHint::CreateInsertion(Tmp.getLocation(),"//");
Diag(Tmp, diag::ext_pp_extra_tokens_at_eol) << DirType << Hint;
DiscardUntilEndOfDirective();
}
}
/// SkipExcludedConditionalBlock - We just read a \#if or related directive and
/// decided that the subsequent tokens are in the \#if'd out portion of the
/// file. Lex the rest of the file, until we see an \#endif. If
/// FoundNonSkipPortion is true, then we have already emitted code for part of
/// this \#if directive, so \#else/\#elif blocks should never be entered.
/// If ElseOk is true, then \#else directives are ok, if not, then we have
/// already seen one so a \#else directive is a duplicate. When this returns,
/// the caller can lex the first valid token.
void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
bool FoundNonSkipPortion,
bool FoundElse,
SourceLocation ElseLoc) {
++NumSkipped;
assert(!CurTokenLexer && CurPPLexer && "Lexing a macro, not a file?");
CurPPLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false,
FoundNonSkipPortion, FoundElse);
if (CurPTHLexer) {
PTHSkipExcludedConditionalBlock();
return;
}
// Enter raw mode to disable identifier lookup (and thus macro expansion),
// disabling warnings, etc.
CurPPLexer->LexingRawMode = true;
Token Tok;
while (1) {
CurLexer->Lex(Tok);
if (Tok.is(tok::code_completion)) {
if (CodeComplete)
CodeComplete->CodeCompleteInConditionalExclusion();
setCodeCompletionReached();
continue;
}
// If this is the end of the buffer, we have an error.
if (Tok.is(tok::eof)) {
// Emit errors for each unterminated conditional on the stack, including
// the current one.
while (!CurPPLexer->ConditionalStack.empty()) {
if (CurLexer->getFileLoc() != CodeCompletionFileLoc)
Diag(CurPPLexer->ConditionalStack.back().IfLoc,
diag::err_pp_unterminated_conditional);
CurPPLexer->ConditionalStack.pop_back();
}
// Just return and let the caller lex after this #include.
break;
}
// If this token is not a preprocessor directive, just skip it.
if (Tok.isNot(tok::hash) || !Tok.isAtStartOfLine())
continue;
// We just parsed a # character at the start of a line, so we're in
// directive mode. Tell the lexer this so any newlines we see will be
// converted into an EOD token (this terminates the macro).
CurPPLexer->ParsingPreprocessorDirective = true;
if (CurLexer) CurLexer->SetKeepWhitespaceMode(false);
// Read the next token, the directive flavor.
LexUnexpandedToken(Tok);
// If this isn't an identifier directive (e.g. is "# 1\n" or "#\n", or
// something bogus), skip it.
if (Tok.isNot(tok::raw_identifier)) {
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->resetExtendedTokenMode();
continue;
}
// If the first letter isn't i or e, it isn't intesting to us. We know that
// this is safe in the face of spelling differences, because there is no way
// to spell an i/e in a strange way that is another letter. Skipping this
// allows us to avoid looking up the identifier info for #define/#undef and
// other common directives.
StringRef RI = Tok.getRawIdentifier();
char FirstChar = RI[0];
if (FirstChar >= 'a' && FirstChar <= 'z' &&
FirstChar != 'i' && FirstChar != 'e') {
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->resetExtendedTokenMode();
continue;
}
// Get the identifier name without trigraphs or embedded newlines. Note
// that we can't use Tok.getIdentifierInfo() because its lookup is disabled
// when skipping.
char DirectiveBuf[20];
StringRef Directive;
if (!Tok.needsCleaning() && RI.size() < 20) {
Directive = RI;
} else {
std::string DirectiveStr = getSpelling(Tok);
unsigned IdLen = DirectiveStr.size();
if (IdLen >= 20) {
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->resetExtendedTokenMode();
continue;
}
memcpy(DirectiveBuf, &DirectiveStr[0], IdLen);
Directive = StringRef(DirectiveBuf, IdLen);
}
if (Directive.startswith("if")) {
StringRef Sub = Directive.substr(2);
if (Sub.empty() || // "if"
Sub == "def" || // "ifdef"
Sub == "ndef") { // "ifndef"
// We know the entire #if/#ifdef/#ifndef block will be skipped, don't
// bother parsing the condition.
DiscardUntilEndOfDirective();
CurPPLexer->pushConditionalLevel(Tok.getLocation(), /*wasskipping*/true,
/*foundnonskip*/false,
/*foundelse*/false);
}
} else if (Directive[0] == 'e') {
StringRef Sub = Directive.substr(1);
if (Sub == "ndif") { // "endif"
PPConditionalInfo CondInfo;
CondInfo.WasSkipping = true; // Silence bogus warning.
bool InCond = CurPPLexer->popConditionalLevel(CondInfo);
(void)InCond; // Silence warning in no-asserts mode.
assert(!InCond && "Can't be skipping if not in a conditional!");
// If we popped the outermost skipping block, we're done skipping!
if (!CondInfo.WasSkipping) {
// Restore the value of LexingRawMode so that trailing comments
// are handled correctly, if we've reached the outermost block.
CurPPLexer->LexingRawMode = false;
CheckEndOfDirective("endif");
CurPPLexer->LexingRawMode = true;
if (Callbacks)
Callbacks->Endif(Tok.getLocation(), CondInfo.IfLoc);
break;
} else {
DiscardUntilEndOfDirective();
}
} else if (Sub == "lse") { // "else".
// #else directive in a skipping conditional. If not in some other
// skipping conditional, and if #else hasn't already been seen, enter it
// as a non-skipping conditional.
PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel();
// If this is a #else with a #else before it, report the error.
if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_else_after_else);
// Note that we've seen a #else in this conditional.
CondInfo.FoundElse = true;
// If the conditional is at the top level, and the #if block wasn't
// entered, enter the #else block now.
if (!CondInfo.WasSkipping && !CondInfo.FoundNonSkip) {
CondInfo.FoundNonSkip = true;
// Restore the value of LexingRawMode so that trailing comments
// are handled correctly.
CurPPLexer->LexingRawMode = false;
CheckEndOfDirective("else");
CurPPLexer->LexingRawMode = true;
if (Callbacks)
Callbacks->Else(Tok.getLocation(), CondInfo.IfLoc);
break;
} else {
DiscardUntilEndOfDirective(); // C99 6.10p4.
}
} else if (Sub == "lif") { // "elif".
PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel();
// If this is a #elif with a #else before it, report the error.
if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_elif_after_else);
// If this is in a skipping block or if we're already handled this #if
// block, don't bother parsing the condition.
if (CondInfo.WasSkipping || CondInfo.FoundNonSkip) {
DiscardUntilEndOfDirective();
} else {
const SourceLocation CondBegin = CurPPLexer->getSourceLocation();
// Restore the value of LexingRawMode so that identifiers are
// looked up, etc, inside the #elif expression.
assert(CurPPLexer->LexingRawMode && "We have to be skipping here!");
CurPPLexer->LexingRawMode = false;
IdentifierInfo *IfNDefMacro = nullptr;
const bool CondValue = EvaluateDirectiveExpression(IfNDefMacro);
CurPPLexer->LexingRawMode = true;
if (Callbacks) {
const SourceLocation CondEnd = CurPPLexer->getSourceLocation();
Callbacks->Elif(Tok.getLocation(),
SourceRange(CondBegin, CondEnd),
(CondValue ? PPCallbacks::CVK_True : PPCallbacks::CVK_False), CondInfo.IfLoc);
}
// If this condition is true, enter it!
if (CondValue) {
CondInfo.FoundNonSkip = true;
break;
}
}
}
}
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->resetExtendedTokenMode();
}
// Finally, if we are out of the conditional (saw an #endif or ran off the end
// of the file, just stop skipping and return to lexing whatever came after
// the #if block.
CurPPLexer->LexingRawMode = false;
if (Callbacks) {
SourceLocation BeginLoc = ElseLoc.isValid() ? ElseLoc : IfTokenLoc;
Callbacks->SourceRangeSkipped(SourceRange(BeginLoc, Tok.getLocation()));
}
}
void Preprocessor::PTHSkipExcludedConditionalBlock() {
while (1) {
assert(CurPTHLexer);
assert(CurPTHLexer->LexingRawMode == false);
// Skip to the next '#else', '#elif', or #endif.
if (CurPTHLexer->SkipBlock()) {
// We have reached an #endif. Both the '#' and 'endif' tokens
// have been consumed by the PTHLexer. Just pop off the condition level.
PPConditionalInfo CondInfo;
bool InCond = CurPTHLexer->popConditionalLevel(CondInfo);
(void)InCond; // Silence warning in no-asserts mode.
assert(!InCond && "Can't be skipping if not in a conditional!");
break;
}
// We have reached a '#else' or '#elif'. Lex the next token to get
// the directive flavor.
Token Tok;
LexUnexpandedToken(Tok);
// We can actually look up the IdentifierInfo here since we aren't in
// raw mode.
tok::PPKeywordKind K = Tok.getIdentifierInfo()->getPPKeywordID();
if (K == tok::pp_else) {
// #else: Enter the else condition. We aren't in a nested condition
// since we skip those. We're always in the one matching the last
// blocked we skipped.
PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel();
// Note that we've seen a #else in this conditional.
CondInfo.FoundElse = true;
// If the #if block wasn't entered then enter the #else block now.
if (!CondInfo.FoundNonSkip) {
CondInfo.FoundNonSkip = true;
// Scan until the eod token.
CurPTHLexer->ParsingPreprocessorDirective = true;
DiscardUntilEndOfDirective();
CurPTHLexer->ParsingPreprocessorDirective = false;
break;
}
// Otherwise skip this block.
continue;
}
assert(K == tok::pp_elif);
PPConditionalInfo &CondInfo = CurPTHLexer->peekConditionalLevel();
// If this is a #elif with a #else before it, report the error.
if (CondInfo.FoundElse)
Diag(Tok, diag::pp_err_elif_after_else);
// If this is in a skipping block or if we're already handled this #if
// block, don't bother parsing the condition. We just skip this block.
if (CondInfo.FoundNonSkip)
continue;
// Evaluate the condition of the #elif.
IdentifierInfo *IfNDefMacro = nullptr;
CurPTHLexer->ParsingPreprocessorDirective = true;
bool ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro);
CurPTHLexer->ParsingPreprocessorDirective = false;
// If this condition is true, enter it!
if (ShouldEnter) {
CondInfo.FoundNonSkip = true;
break;
}
// Otherwise, skip this block and go to the next one.
continue;
}
}
Module *Preprocessor::getModuleForLocation(SourceLocation Loc) {
ModuleMap &ModMap = HeaderInfo.getModuleMap();
if (SourceMgr.isInMainFile(Loc)) {
if (Module *CurMod = getCurrentModule())
return CurMod; // Compiling a module.
return HeaderInfo.getModuleMap().SourceModule; // Compiling a source.
}
// Try to determine the module of the include directive.
// FIXME: Look into directly passing the FileEntry from LookupFile instead.
FileID IDOfIncl = SourceMgr.getFileID(SourceMgr.getExpansionLoc(Loc));
if (const FileEntry *EntryOfIncl = SourceMgr.getFileEntryForID(IDOfIncl)) {
// The include comes from a file.
return ModMap.findModuleForHeader(EntryOfIncl).getModule();
} else {
// The include does not come from a file,
// so it is probably a module compilation.
return getCurrentModule();
}
}
Module *Preprocessor::getModuleContainingLocation(SourceLocation Loc) {
return HeaderInfo.getModuleMap().inferModuleFromLocation(
FullSourceLoc(Loc, SourceMgr));
}
const FileEntry *Preprocessor::LookupFile(
SourceLocation FilenameLoc,
StringRef Filename,
bool isAngled,
const DirectoryLookup *FromDir,
const FileEntry *FromFile,
const DirectoryLookup *&CurDir,
SmallVectorImpl<char> *SearchPath,
SmallVectorImpl<char> *RelativePath,
ModuleMap::KnownHeader *SuggestedModule,
bool SkipCache) {
// If the header lookup mechanism may be relative to the current inclusion
// stack, record the parent #includes.
SmallVector<std::pair<const FileEntry *, const DirectoryEntry *>, 16>
Includers;
if (!FromDir && !FromFile) {
FileID FID = getCurrentFileLexer()->getFileID();
const FileEntry *FileEnt = SourceMgr.getFileEntryForID(FID);
// If there is no file entry associated with this file, it must be the
// predefines buffer or the module includes buffer. Any other file is not
// lexed with a normal lexer, so it won't be scanned for preprocessor
// directives.
//
// If we have the predefines buffer, resolve #include references (which come
// from the -include command line argument) from the current working
// directory instead of relative to the main file.
//
// If we have the module includes buffer, resolve #include references (which
// come from header declarations in the module map) relative to the module
// map file.
if (!FileEnt) {
if (FID == SourceMgr.getMainFileID() && MainFileDir)
Includers.push_back(std::make_pair(nullptr, MainFileDir));
else if ((FileEnt =
SourceMgr.getFileEntryForID(SourceMgr.getMainFileID())))
Includers.push_back(std::make_pair(FileEnt, FileMgr.getDirectory(".")));
} else {
Includers.push_back(std::make_pair(FileEnt, FileEnt->getDir()));
}
// MSVC searches the current include stack from top to bottom for
// headers included by quoted include directives.
// See: http://msdn.microsoft.com/en-us/library/36k2cdd4.aspx
if (LangOpts.MSVCCompat && !isAngled) {
for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) {
IncludeStackInfo &ISEntry = IncludeMacroStack[e - i - 1];
if (IsFileLexer(ISEntry))
if ((FileEnt = SourceMgr.getFileEntryForID(
ISEntry.ThePPLexer->getFileID())))
Includers.push_back(std::make_pair(FileEnt, FileEnt->getDir()));
}
}
}
CurDir = CurDirLookup;
if (FromFile) {
// We're supposed to start looking from after a particular file. Search
// the include path until we find that file or run out of files.
const DirectoryLookup *TmpCurDir = CurDir;
const DirectoryLookup *TmpFromDir = nullptr;
while (const FileEntry *FE = HeaderInfo.LookupFile(
Filename, FilenameLoc, isAngled, TmpFromDir, TmpCurDir,
Includers, SearchPath, RelativePath, SuggestedModule,
SkipCache)) {
// Keep looking as if this file did a #include_next.
TmpFromDir = TmpCurDir;
++TmpFromDir;
if (FE == FromFile) {
// Found it.
FromDir = TmpFromDir;
CurDir = TmpCurDir;
break;
}
}
}
// Do a standard file entry lookup.
const FileEntry *FE = HeaderInfo.LookupFile(
Filename, FilenameLoc, isAngled, FromDir, CurDir, Includers, SearchPath,
RelativePath, SuggestedModule, SkipCache);
if (FE) {
if (SuggestedModule && !LangOpts.AsmPreprocessor)
HeaderInfo.getModuleMap().diagnoseHeaderInclusion(
getModuleForLocation(FilenameLoc), FilenameLoc, Filename, FE);
return FE;
}
const FileEntry *CurFileEnt;
// Otherwise, see if this is a subframework header. If so, this is relative
// to one of the headers on the #include stack. Walk the list of the current
// headers on the #include stack and pass them to HeaderInfo.
if (IsFileLexer()) {
if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID()))) {
if ((FE = HeaderInfo.LookupSubframeworkHeader(Filename, CurFileEnt,
SearchPath, RelativePath,
SuggestedModule))) {
if (SuggestedModule && !LangOpts.AsmPreprocessor)
HeaderInfo.getModuleMap().diagnoseHeaderInclusion(
getModuleForLocation(FilenameLoc), FilenameLoc, Filename, FE);
return FE;
}
}
}
for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) {
IncludeStackInfo &ISEntry = IncludeMacroStack[e-i-1];
if (IsFileLexer(ISEntry)) {
if ((CurFileEnt =
SourceMgr.getFileEntryForID(ISEntry.ThePPLexer->getFileID()))) {
if ((FE = HeaderInfo.LookupSubframeworkHeader(
Filename, CurFileEnt, SearchPath, RelativePath,
SuggestedModule))) {
if (SuggestedModule && !LangOpts.AsmPreprocessor)
HeaderInfo.getModuleMap().diagnoseHeaderInclusion(
getModuleForLocation(FilenameLoc), FilenameLoc, Filename, FE);
return FE;
}
}
}
}
// Otherwise, we really couldn't find the file.
return nullptr;
}
//===----------------------------------------------------------------------===//
// Preprocessor Directive Handling.
//===----------------------------------------------------------------------===//
class Preprocessor::ResetMacroExpansionHelper {
public:
ResetMacroExpansionHelper(Preprocessor *pp)
: PP(pp), save(pp->DisableMacroExpansion) {
if (pp->MacroExpansionInDirectivesOverride)
pp->DisableMacroExpansion = false;
}
~ResetMacroExpansionHelper() {
PP->DisableMacroExpansion = save;
}
private:
Preprocessor *PP;
bool save;
};
/// HandleDirective - This callback is invoked when the lexer sees a # token
/// at the start of a line. This consumes the directive, modifies the
/// lexer/preprocessor state, and advances the lexer(s) so that the next token
/// read is the correct one.
void Preprocessor::HandleDirective(Token &Result) {
// FIXME: Traditional: # with whitespace before it not recognized by K&R?
// We just parsed a # character at the start of a line, so we're in directive
// mode. Tell the lexer this so any newlines we see will be converted into an
// EOD token (which terminates the directive).
CurPPLexer->ParsingPreprocessorDirective = true;
if (CurLexer) CurLexer->SetKeepWhitespaceMode(false);
bool ImmediatelyAfterTopLevelIfndef =
CurPPLexer->MIOpt.getImmediatelyAfterTopLevelIfndef();
CurPPLexer->MIOpt.resetImmediatelyAfterTopLevelIfndef();
++NumDirectives;
// We are about to read a token. For the multiple-include optimization FA to
// work, we have to remember if we had read any tokens *before* this
// pp-directive.
bool ReadAnyTokensBeforeDirective =CurPPLexer->MIOpt.getHasReadAnyTokensVal();
// Save the '#' token in case we need to return it later.
Token SavedHash = Result;
// Read the next token, the directive flavor. This isn't expanded due to
// C99 6.10.3p8.
LexUnexpandedToken(Result);
// C99 6.10.3p11: Is this preprocessor directive in macro invocation? e.g.:
// #define A(x) #x
// A(abc
// #warning blah
// def)
// If so, the user is relying on undefined behavior, emit a diagnostic. Do
// not support this for #include-like directives, since that can result in
// terrible diagnostics, and does not work in GCC.
if (InMacroArgs) {
if (IdentifierInfo *II = Result.getIdentifierInfo()) {
switch (II->getPPKeywordID()) {
case tok::pp_include:
case tok::pp_import:
case tok::pp_include_next:
case tok::pp___include_macros:
case tok::pp_pragma:
Diag(Result, diag::err_embedded_directive) << II->getName();
DiscardUntilEndOfDirective();
return;
default:
break;
}
}
Diag(Result, diag::ext_embedded_directive);
}
// Temporarily enable macro expansion if set so
// and reset to previous state when returning from this function.
ResetMacroExpansionHelper helper(this);
switch (Result.getKind()) {
case tok::eod:
return; // null directive.
case tok::code_completion:
if (CodeComplete)
CodeComplete->CodeCompleteDirective(
CurPPLexer->getConditionalStackDepth() > 0);
setCodeCompletionReached();
return;
case tok::numeric_constant: // # 7 GNU line marker directive.
if (getLangOpts().AsmPreprocessor)
break; // # 4 is not a preprocessor directive in .S files.
return HandleDigitDirective(Result);
default:
IdentifierInfo *II = Result.getIdentifierInfo();
if (!II) break; // Not an identifier.
// Ask what the preprocessor keyword ID is.
switch (II->getPPKeywordID()) {
default: break;
// C99 6.10.1 - Conditional Inclusion.
case tok::pp_if:
return HandleIfDirective(Result, ReadAnyTokensBeforeDirective);
case tok::pp_ifdef:
return HandleIfdefDirective(Result, false, true/*not valid for miopt*/);
case tok::pp_ifndef:
return HandleIfdefDirective(Result, true, ReadAnyTokensBeforeDirective);
case tok::pp_elif:
return HandleElifDirective(Result);
case tok::pp_else:
return HandleElseDirective(Result);
case tok::pp_endif:
return HandleEndifDirective(Result);
// C99 6.10.2 - Source File Inclusion.
case tok::pp_include:
// Handle #include.
return HandleIncludeDirective(SavedHash.getLocation(), Result);
case tok::pp___include_macros:
// Handle -imacros.
return HandleIncludeMacrosDirective(SavedHash.getLocation(), Result);
// C99 6.10.3 - Macro Replacement.
case tok::pp_define:
return HandleDefineDirective(Result, ImmediatelyAfterTopLevelIfndef);
case tok::pp_undef:
return HandleUndefDirective(Result);
// C99 6.10.4 - Line Control.
case tok::pp_line:
return HandleLineDirective(Result);
// C99 6.10.5 - Error Directive.
case tok::pp_error:
return HandleUserDiagnosticDirective(Result, false);
// C99 6.10.6 - Pragma Directive.
case tok::pp_pragma:
return HandlePragmaDirective(SavedHash.getLocation(), PIK_HashPragma);
// GNU Extensions.
case tok::pp_import:
return HandleImportDirective(SavedHash.getLocation(), Result);
case tok::pp_include_next:
return HandleIncludeNextDirective(SavedHash.getLocation(), Result);
case tok::pp_warning:
Diag(Result, diag::ext_pp_warning_directive);
return HandleUserDiagnosticDirective(Result, true);
case tok::pp_ident:
return HandleIdentSCCSDirective(Result);
case tok::pp_sccs:
return HandleIdentSCCSDirective(Result);
case tok::pp_assert:
//isExtension = true; // FIXME: implement #assert
break;
case tok::pp_unassert:
//isExtension = true; // FIXME: implement #unassert
break;
case tok::pp___public_macro:
if (getLangOpts().Modules)
return HandleMacroPublicDirective(Result);
break;
case tok::pp___private_macro:
if (getLangOpts().Modules)
return HandleMacroPrivateDirective(Result);
break;
}
break;
}
// If this is a .S file, treat unknown # directives as non-preprocessor
// directives. This is important because # may be a comment or introduce
// various pseudo-ops. Just return the # token and push back the following
// token to be lexed next time.
if (getLangOpts().AsmPreprocessor) {
Token *Toks = new Token[2];
// Return the # and the token after it.
Toks[0] = SavedHash;
Toks[1] = Result;
// If the second token is a hashhash token, then we need to translate it to
// unknown so the token lexer doesn't try to perform token pasting.
if (Result.is(tok::hashhash))
Toks[1].setKind(tok::unknown);
// Enter this token stream so that we re-lex the tokens. Make sure to
// enable macro expansion, in case the token after the # is an identifier
// that is expanded.
EnterTokenStream(Toks, 2, false, true);
return;
}
// If we reached here, the preprocessing token is not valid!
Diag(Result, diag::err_pp_invalid_directive);
// Read the rest of the PP line.
DiscardUntilEndOfDirective();
// Okay, we're done parsing the directive.
}
/// GetLineValue - Convert a numeric token into an unsigned value, emitting
/// Diagnostic DiagID if it is invalid, and returning the value in Val.
static bool GetLineValue(Token &DigitTok, unsigned &Val,
unsigned DiagID, Preprocessor &PP,
bool IsGNULineDirective=false) {
if (DigitTok.isNot(tok::numeric_constant)) {
PP.Diag(DigitTok, DiagID);
if (DigitTok.isNot(tok::eod))
PP.DiscardUntilEndOfDirective();
return true;
}
SmallString<64> IntegerBuffer;
IntegerBuffer.resize(DigitTok.getLength());
const char *DigitTokBegin = &IntegerBuffer[0];
bool Invalid = false;
unsigned ActualLength = PP.getSpelling(DigitTok, DigitTokBegin, &Invalid);
if (Invalid)
return true;
// Verify that we have a simple digit-sequence, and compute the value. This
// is always a simple digit string computed in decimal, so we do this manually
// here.
Val = 0;
for (unsigned i = 0; i != ActualLength; ++i) {
// C++1y [lex.fcon]p1:
// Optional separating single quotes in a digit-sequence are ignored
if (DigitTokBegin[i] == '\'')
continue;
if (!isDigit(DigitTokBegin[i])) {
PP.Diag(PP.AdvanceToTokenCharacter(DigitTok.getLocation(), i),
diag::err_pp_line_digit_sequence) << IsGNULineDirective;
PP.DiscardUntilEndOfDirective();
return true;
}
unsigned NextVal = Val*10+(DigitTokBegin[i]-'0');
if (NextVal < Val) { // overflow.
PP.Diag(DigitTok, DiagID);
PP.DiscardUntilEndOfDirective();
return true;
}
Val = NextVal;
}
if (DigitTokBegin[0] == '0' && Val)
PP.Diag(DigitTok.getLocation(), diag::warn_pp_line_decimal)
<< IsGNULineDirective;
return false;
}
/// \brief Handle a \#line directive: C99 6.10.4.
///
/// The two acceptable forms are:
/// \verbatim
/// # line digit-sequence
/// # line digit-sequence "s-char-sequence"
/// \endverbatim
void Preprocessor::HandleLineDirective(Token &Tok) {
// Read the line # and string argument. Per C99 6.10.4p5, these tokens are
// expanded.
Token DigitTok;
Lex(DigitTok);
// Validate the number and convert it to an unsigned.
unsigned LineNo;
if (GetLineValue(DigitTok, LineNo, diag::err_pp_line_requires_integer,*this))
return;
if (LineNo == 0)
Diag(DigitTok, diag::ext_pp_line_zero);
// Enforce C99 6.10.4p3: "The digit sequence shall not specify ... a
// number greater than 2147483647". C90 requires that the line # be <= 32767.
unsigned LineLimit = 32768U;
if (LangOpts.C99 || LangOpts.CPlusPlus11)
LineLimit = 2147483648U;
if (LineNo >= LineLimit)
Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit;
else if (LangOpts.CPlusPlus11 && LineNo >= 32768U)
Diag(DigitTok, diag::warn_cxx98_compat_pp_line_too_big);
int FilenameID = -1;
Token StrTok;
Lex(StrTok);
// If the StrTok is "eod", then it wasn't present. Otherwise, it must be a
// string followed by eod.
if (StrTok.is(tok::eod))
; // ok
else if (StrTok.isNot(tok::string_literal)) {
Diag(StrTok, diag::err_pp_line_invalid_filename);
return DiscardUntilEndOfDirective();
} else if (StrTok.hasUDSuffix()) {
Diag(StrTok, diag::err_invalid_string_udl);
return DiscardUntilEndOfDirective();
} else {
// Parse and validate the string, converting it into a unique ID.
StringLiteralParser Literal(StrTok, *this);
assert(Literal.isAscii() && "Didn't allow wide strings in");
if (Literal.hadError)
return DiscardUntilEndOfDirective();
if (Literal.Pascal) {
Diag(StrTok, diag::err_pp_linemarker_invalid_filename);
return DiscardUntilEndOfDirective();
}
FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString());
// Verify that there is nothing after the string, other than EOD. Because
// of C99 6.10.4p5, macros that expand to empty tokens are ok.
CheckEndOfDirective("line", true);
}
SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID);
if (Callbacks)
Callbacks->FileChanged(CurPPLexer->getSourceLocation(),
PPCallbacks::RenameFile,
SrcMgr::C_User);
}
/// ReadLineMarkerFlags - Parse and validate any flags at the end of a GNU line
/// marker directive.
static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit,
bool &IsSystemHeader, bool &IsExternCHeader,
Preprocessor &PP) {
unsigned FlagVal;
Token FlagTok;
PP.Lex(FlagTok);
if (FlagTok.is(tok::eod)) return false;
if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP))
return true;
if (FlagVal == 1) {
IsFileEntry = true;
PP.Lex(FlagTok);
if (FlagTok.is(tok::eod)) return false;
if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP))
return true;
} else if (FlagVal == 2) {
IsFileExit = true;
SourceManager &SM = PP.getSourceManager();
// If we are leaving the current presumed file, check to make sure the
// presumed include stack isn't empty!
FileID CurFileID =
SM.getDecomposedExpansionLoc(FlagTok.getLocation()).first;
PresumedLoc PLoc = SM.getPresumedLoc(FlagTok.getLocation());
if (PLoc.isInvalid())
return true;
// If there is no include loc (main file) or if the include loc is in a
// different physical file, then we aren't in a "1" line marker flag region.
SourceLocation IncLoc = PLoc.getIncludeLoc();
if (IncLoc.isInvalid() ||
SM.getDecomposedExpansionLoc(IncLoc).first != CurFileID) {
PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_pop);
PP.DiscardUntilEndOfDirective();
return true;
}
PP.Lex(FlagTok);
if (FlagTok.is(tok::eod)) return false;
if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag,PP))
return true;
}
// We must have 3 if there are still flags.
if (FlagVal != 3) {
PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag);
PP.DiscardUntilEndOfDirective();
return true;
}
IsSystemHeader = true;
PP.Lex(FlagTok);
if (FlagTok.is(tok::eod)) return false;
if (GetLineValue(FlagTok, FlagVal, diag::err_pp_linemarker_invalid_flag, PP))
return true;
// We must have 4 if there is yet another flag.
if (FlagVal != 4) {
PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag);
PP.DiscardUntilEndOfDirective();
return true;
}
IsExternCHeader = true;
PP.Lex(FlagTok);
if (FlagTok.is(tok::eod)) return false;
// There are no more valid flags here.
PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_flag);
PP.DiscardUntilEndOfDirective();
return true;
}
/// HandleDigitDirective - Handle a GNU line marker directive, whose syntax is
/// one of the following forms:
///
/// # 42
/// # 42 "file" ('1' | '2')?
/// # 42 "file" ('1' | '2')? '3' '4'?
///
void Preprocessor::HandleDigitDirective(Token &DigitTok) {
// Validate the number and convert it to an unsigned. GNU does not have a
// line # limit other than it fit in 32-bits.
unsigned LineNo;
if (GetLineValue(DigitTok, LineNo, diag::err_pp_linemarker_requires_integer,
*this, true))
return;
Token StrTok;
Lex(StrTok);
bool IsFileEntry = false, IsFileExit = false;
bool IsSystemHeader = false, IsExternCHeader = false;
int FilenameID = -1;
// If the StrTok is "eod", then it wasn't present. Otherwise, it must be a
// string followed by eod.
if (StrTok.is(tok::eod))
; // ok
else if (StrTok.isNot(tok::string_literal)) {
Diag(StrTok, diag::err_pp_linemarker_invalid_filename);
return DiscardUntilEndOfDirective();
} else if (StrTok.hasUDSuffix()) {
Diag(StrTok, diag::err_invalid_string_udl);
return DiscardUntilEndOfDirective();
} else {
// Parse and validate the string, converting it into a unique ID.
StringLiteralParser Literal(StrTok, *this);
assert(Literal.isAscii() && "Didn't allow wide strings in");
if (Literal.hadError)
return DiscardUntilEndOfDirective();
if (Literal.Pascal) {
Diag(StrTok, diag::err_pp_linemarker_invalid_filename);
return DiscardUntilEndOfDirective();
}
FilenameID = SourceMgr.getLineTableFilenameID(Literal.GetString());
// If a filename was present, read any flags that are present.
if (ReadLineMarkerFlags(IsFileEntry, IsFileExit,
IsSystemHeader, IsExternCHeader, *this))
return;
}
// Create a line note with this information.
SourceMgr.AddLineNote(DigitTok.getLocation(), LineNo, FilenameID,
IsFileEntry, IsFileExit,
IsSystemHeader, IsExternCHeader);
// If the preprocessor has callbacks installed, notify them of the #line
// change. This is used so that the line marker comes out in -E mode for
// example.
if (Callbacks) {
PPCallbacks::FileChangeReason Reason = PPCallbacks::RenameFile;
if (IsFileEntry)
Reason = PPCallbacks::EnterFile;
else if (IsFileExit)
Reason = PPCallbacks::ExitFile;
SrcMgr::CharacteristicKind FileKind = SrcMgr::C_User;
if (IsExternCHeader)
FileKind = SrcMgr::C_ExternCSystem;
else if (IsSystemHeader)
FileKind = SrcMgr::C_System;
Callbacks->FileChanged(CurPPLexer->getSourceLocation(), Reason, FileKind);
}
}
/// HandleUserDiagnosticDirective - Handle a #warning or #error directive.
///
void Preprocessor::HandleUserDiagnosticDirective(Token &Tok,
bool isWarning) {
// PTH doesn't emit #warning or #error directives.
if (CurPTHLexer)
return CurPTHLexer->DiscardToEndOfLine();
// Read the rest of the line raw. We do this because we don't want macros
// to be expanded and we don't require that the tokens be valid preprocessing
// tokens. For example, this is allowed: "#warning ` 'foo". GCC does
// collapse multiple consequtive white space between tokens, but this isn't
// specified by the standard.
SmallString<128> Message;
CurLexer->ReadToEndOfLine(&Message);
// Find the first non-whitespace character, so that we can make the
// diagnostic more succinct.
StringRef Msg = StringRef(Message).ltrim(" ");
if (isWarning)
Diag(Tok, diag::pp_hash_warning) << Msg;
else
Diag(Tok, diag::err_pp_hash_error) << Msg;
}
/// HandleIdentSCCSDirective - Handle a #ident/#sccs directive.
///
void Preprocessor::HandleIdentSCCSDirective(Token &Tok) {
// Yes, this directive is an extension.
Diag(Tok, diag::ext_pp_ident_directive);
// Read the string argument.
Token StrTok;
Lex(StrTok);
// If the token kind isn't a string, it's a malformed directive.
if (StrTok.isNot(tok::string_literal) &&
StrTok.isNot(tok::wide_string_literal)) {
Diag(StrTok, diag::err_pp_malformed_ident);
if (StrTok.isNot(tok::eod))
DiscardUntilEndOfDirective();
return;
}
if (StrTok.hasUDSuffix()) {
Diag(StrTok, diag::err_invalid_string_udl);
return DiscardUntilEndOfDirective();
}
// Verify that there is nothing after the string, other than EOD.
CheckEndOfDirective("ident");
if (Callbacks) {
bool Invalid = false;
std::string Str = getSpelling(StrTok, &Invalid);
if (!Invalid)
Callbacks->Ident(Tok.getLocation(), Str);
}
}
/// \brief Handle a #public directive.
void Preprocessor::HandleMacroPublicDirective(Token &Tok) {
Token MacroNameTok;
ReadMacroName(MacroNameTok, MU_Undef);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.is(tok::eod))
return;
// Check to see if this is the last token on the #__public_macro line.
CheckEndOfDirective("__public_macro");
IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
// Okay, we finally have a valid identifier to undef.
MacroDirective *MD = getLocalMacroDirective(II);
// If the macro is not defined, this is an error.
if (!MD) {
Diag(MacroNameTok, diag::err_pp_visibility_non_macro) << II;
return;
}
// Note that this macro has now been exported.
appendMacroDirective(II, AllocateVisibilityMacroDirective(
MacroNameTok.getLocation(), /*IsPublic=*/true));
}
/// \brief Handle a #private directive.
void Preprocessor::HandleMacroPrivateDirective(Token &Tok) {
Token MacroNameTok;
ReadMacroName(MacroNameTok, MU_Undef);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.is(tok::eod))
return;
// Check to see if this is the last token on the #__private_macro line.
CheckEndOfDirective("__private_macro");
IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
// Okay, we finally have a valid identifier to undef.
MacroDirective *MD = getLocalMacroDirective(II);
// If the macro is not defined, this is an error.
if (!MD) {
Diag(MacroNameTok, diag::err_pp_visibility_non_macro) << II;
return;
}
// Note that this macro has now been marked private.
appendMacroDirective(II, AllocateVisibilityMacroDirective(
MacroNameTok.getLocation(), /*IsPublic=*/false));
}
//===----------------------------------------------------------------------===//
// Preprocessor Include Directive Handling.
//===----------------------------------------------------------------------===//
/// GetIncludeFilenameSpelling - Turn the specified lexer token into a fully
/// checked and spelled filename, e.g. as an operand of \#include. This returns
/// true if the input filename was in <>'s or false if it were in ""'s. The
/// caller is expected to provide a buffer that is large enough to hold the
/// spelling of the filename, but is also expected to handle the case when
/// this method decides to use a different buffer.
bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc,
StringRef &Buffer) {
// Get the text form of the filename.
assert(!Buffer.empty() && "Can't have tokens with empty spellings!");
// Make sure the filename is <x> or "x".
bool isAngled;
if (Buffer[0] == '<') {
if (Buffer.back() != '>') {
Diag(Loc, diag::err_pp_expects_filename);
Buffer = StringRef();
return true;
}
isAngled = true;
} else if (Buffer[0] == '"') {
if (Buffer.back() != '"') {
Diag(Loc, diag::err_pp_expects_filename);
Buffer = StringRef();
return true;
}
isAngled = false;
} else {
Diag(Loc, diag::err_pp_expects_filename);
Buffer = StringRef();
return true;
}
// Diagnose #include "" as invalid.
if (Buffer.size() <= 2) {
Diag(Loc, diag::err_pp_empty_filename);
Buffer = StringRef();
return true;
}
// Skip the brackets.
Buffer = Buffer.substr(1, Buffer.size()-2);
return isAngled;
}
// \brief Handle cases where the \#include name is expanded from a macro
// as multiple tokens, which need to be glued together.
//
// This occurs for code like:
// \code
// \#define FOO <a/b.h>
// \#include FOO
// \endcode
// 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 EOD marker.
bool Preprocessor::ConcatenateIncludeName(SmallString<128> &FilenameBuffer,
SourceLocation &End) {
Token CurTok;
Lex(CurTok);
while (CurTok.isNot(tok::eod)) {
End = CurTok.getLocation();
// FIXME: Provide code completion for #includes.
if (CurTok.is(tok::code_completion)) {
setCodeCompletionReached();
Lex(CurTok);
continue;
}
// Append the spelling of this token to the buffer. If there was a space
// before it, add it now.
if (CurTok.hasLeadingSpace())
FilenameBuffer.push_back(' ');
// Get the spelling of the token, directly into FilenameBuffer if possible.
unsigned PreAppendSize = FilenameBuffer.size();
FilenameBuffer.resize(PreAppendSize+CurTok.getLength());
const char *BufPtr = &FilenameBuffer[PreAppendSize];
unsigned ActualLen = getSpelling(CurTok, BufPtr);
// If the token was spelled somewhere else, copy it into FilenameBuffer.
if (BufPtr != &FilenameBuffer[PreAppendSize])
memcpy(&FilenameBuffer[PreAppendSize], BufPtr, ActualLen);
// Resize FilenameBuffer to the correct size.
if (CurTok.getLength() != ActualLen)
FilenameBuffer.resize(PreAppendSize+ActualLen);
// If we found the '>' marker, return success.
if (CurTok.is(tok::greater))
return false;
Lex(CurTok);
}
// If we hit the eod marker, emit an error and return true so that the caller
// knows the EOD has been read.
Diag(CurTok.getLocation(), diag::err_pp_expects_filename);
return true;
}
/// \brief Push a token onto the token stream containing an annotation.
static void EnterAnnotationToken(Preprocessor &PP,
SourceLocation Begin, SourceLocation End,
tok::TokenKind Kind, void *AnnotationVal) {
// FIXME: Produce this as the current token directly, rather than
// allocating a new token for it.
Token *Tok = new Token[1];
Tok[0].startToken();
Tok[0].setKind(Kind);
Tok[0].setLocation(Begin);
Tok[0].setAnnotationEndLoc(End);
Tok[0].setAnnotationValue(AnnotationVal);
PP.EnterTokenStream(Tok, 1, true, true);
}
/// \brief Produce a diagnostic informing the user that a #include or similar
/// was implicitly treated as a module import.
static void diagnoseAutoModuleImport(
Preprocessor &PP, SourceLocation HashLoc, Token &IncludeTok,
ArrayRef<std::pair<IdentifierInfo *, SourceLocation>> Path,
SourceLocation PathEnd) {
assert(PP.getLangOpts().ObjC2 && "no import syntax available");
SmallString<128> PathString;
for (unsigned I = 0, N = Path.size(); I != N; ++I) {
if (I)
PathString += '.';
PathString += Path[I].first->getName();
}
int IncludeKind = 0;
switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
case tok::pp_include:
IncludeKind = 0;
break;
case tok::pp_import:
IncludeKind = 1;
break;
case tok::pp_include_next:
IncludeKind = 2;
break;
case tok::pp___include_macros:
IncludeKind = 3;
break;
default:
llvm_unreachable("unknown include directive kind");
}
CharSourceRange ReplaceRange(SourceRange(HashLoc, PathEnd),
/*IsTokenRange=*/false);
PP.Diag(HashLoc, diag::warn_auto_module_import)
<< IncludeKind << PathString
<< FixItHint::CreateReplacement(ReplaceRange,
("@import " + PathString + ";").str());
}
/// HandleIncludeDirective - The "\#include" tokens have just been read, read
/// the file to be included from the lexer, then include it! This is a common
/// routine with functionality shared between \#include, \#include_next and
/// \#import. LookupFrom is set when this is a \#include_next directive, it
/// specifies the file to start searching from.
void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
Token &IncludeTok,
const DirectoryLookup *LookupFrom,
const FileEntry *LookupFromFile,
bool isImport) {
Token FilenameTok;
CurPPLexer->LexIncludeFilename(FilenameTok);
// Reserve a buffer to get the spelling.
SmallString<128> FilenameBuffer;
StringRef Filename;
SourceLocation End;
SourceLocation CharEnd; // the end of this directive, in characters
switch (FilenameTok.getKind()) {
case tok::eod:
// If the token kind is EOD, the error has already been diagnosed.
return;
case tok::angle_string_literal:
case tok::string_literal:
Filename = getSpelling(FilenameTok, FilenameBuffer);
End = FilenameTok.getLocation();
CharEnd = End.getLocWithOffset(FilenameTok.getLength());
break;
case tok::less:
// This could be a <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, End))
return; // Found <eod> but no ">"? Diagnostic already emitted.
Filename = FilenameBuffer;
CharEnd = End.getLocWithOffset(1);
break;
default:
Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename);
DiscardUntilEndOfDirective();
return;
}
CharSourceRange FilenameRange
= CharSourceRange::getCharRange(FilenameTok.getLocation(), CharEnd);
StringRef OriginalFilename = Filename;
bool isAngled =
GetIncludeFilenameSpelling(FilenameTok.getLocation(), Filename);
// If GetIncludeFilenameSpelling set the start ptr to null, there was an
// error.
if (Filename.empty()) {
DiscardUntilEndOfDirective();
return;
}
// Verify that there is nothing after the filename, other than EOD. Note that
// we allow macros that expand to nothing after the filename, because this
// falls into the category of "#include pp-tokens new-line" specified in
// C99 6.10.2p4.
CheckEndOfDirective(IncludeTok.getIdentifierInfo()->getNameStart(), true);
// Check that we don't have infinite #include recursion.
if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1) {
Diag(FilenameTok, diag::err_pp_include_too_deep);
return;
}
// Complain about attempts to #include files in an audit pragma.
if (PragmaARCCFCodeAuditedLoc.isValid()) {
Diag(HashLoc, diag::err_pp_include_in_arc_cf_code_audited);
Diag(PragmaARCCFCodeAuditedLoc, diag::note_pragma_entered_here);
// Immediately leave the pragma.
PragmaARCCFCodeAuditedLoc = SourceLocation();
}
if (HeaderInfo.HasIncludeAliasMap()) {
// Map the filename with the brackets still attached. If the name doesn't
// map to anything, fall back on the filename we've already gotten the
// spelling for.
StringRef NewName = HeaderInfo.MapHeaderToIncludeAlias(OriginalFilename);
if (!NewName.empty())
Filename = NewName;
}
// Search include directories.
const DirectoryLookup *CurDir;
SmallString<1024> SearchPath;
SmallString<1024> RelativePath;
// We get the raw path only if we have 'Callbacks' to which we later pass
// the path.
ModuleMap::KnownHeader SuggestedModule;
SourceLocation FilenameLoc = FilenameTok.getLocation();
SmallString<128> NormalizedPath;
if (LangOpts.MSVCCompat) {
NormalizedPath = Filename.str();
#ifndef LLVM_ON_WIN32
llvm::sys::path::native(NormalizedPath);
#endif
}
const FileEntry *File = LookupFile(
FilenameLoc, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename,
isAngled, LookupFrom, LookupFromFile, CurDir,
Callbacks ? &SearchPath : nullptr, Callbacks ? &RelativePath : nullptr,
HeaderInfo.getHeaderSearchOpts().ModuleMaps ? &SuggestedModule : nullptr);
if (!File) {
if (Callbacks) {
// Give the clients a chance to recover.
SmallString<128> RecoveryPath;
if (Callbacks->FileNotFound(Filename, RecoveryPath)) {
if (const DirectoryEntry *DE = FileMgr.getDirectory(RecoveryPath)) {
// Add the recovery path to the list of search paths.
DirectoryLookup DL(DE, SrcMgr::C_User, false);
HeaderInfo.AddSearchPath(DL, isAngled);
// Try the lookup again, skipping the cache.
File = LookupFile(
FilenameLoc,
LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled,
LookupFrom, LookupFromFile, CurDir, nullptr, nullptr,
HeaderInfo.getHeaderSearchOpts().ModuleMaps ? &SuggestedModule
: nullptr,
/*SkipCache*/ true);
}
}
}
if (!SuppressIncludeNotFoundError) {
// If the file could not be located and it was included via angle
// brackets, we can attempt a lookup as though it were a quoted path to
// provide the user with a possible fixit.
if (isAngled) {
File = LookupFile(
FilenameLoc,
LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, false,
LookupFrom, LookupFromFile, CurDir,
Callbacks ? &SearchPath : nullptr,
Callbacks ? &RelativePath : nullptr,
HeaderInfo.getHeaderSearchOpts().ModuleMaps ? &SuggestedModule
: nullptr);
if (File) {
SourceRange Range(FilenameTok.getLocation(), CharEnd);
Diag(FilenameTok, diag::err_pp_file_not_found_not_fatal) <<
Filename <<
FixItHint::CreateReplacement(Range, "\"" + Filename.str() + "\"");
}
}
// If the file is still not found, just go with the vanilla diagnostic
if (!File)
Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
}
}
// Should we enter the source file? Set to false if either the source file is
// known to have no effect beyond its effect on module visibility -- that is,
// if it's got an include guard that is already defined or is a modular header
// we've imported or already built.
bool ShouldEnter = true;
// Determine whether we should try to import the module for this #include, if
// there is one. Don't do so if precompiled module support is disabled or we
// are processing this module textually (because we're building the module).
if (File && SuggestedModule && getLangOpts().Modules &&
SuggestedModule.getModule()->getTopLevelModuleName() !=
getLangOpts().CurrentModule &&
SuggestedModule.getModule()->getTopLevelModuleName() !=
getLangOpts().ImplementationOfModule) {
// Compute the module access path corresponding to this module.
// FIXME: Should we have a second loadModule() overload to avoid this
// extra lookup step?
SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
for (Module *Mod = SuggestedModule.getModule(); Mod; Mod = Mod->Parent)
Path.push_back(std::make_pair(getIdentifierInfo(Mod->Name),
FilenameTok.getLocation()));
std::reverse(Path.begin(), Path.end());
// Warn that we're replacing the include/import with a module import.
// We only do this in Objective-C, where we have a module-import syntax.
if (getLangOpts().ObjC2)
diagnoseAutoModuleImport(*this, HashLoc, IncludeTok, Path, CharEnd);
// Load the module to import its macros. We'll make the declarations
// visible when the parser gets here.
// FIXME: Pass SuggestedModule in here rather than converting it to a path
// and making the module loader convert it back again.
ModuleLoadResult Imported = TheModuleLoader.loadModule(
IncludeTok.getLocation(), Path, Module::Hidden,
/*IsIncludeDirective=*/true);
assert((Imported == nullptr || Imported == SuggestedModule.getModule()) &&
"the imported module is different than the suggested one");
if (Imported)
ShouldEnter = false;
else if (Imported.isMissingExpected()) {
// We failed to find a submodule that we assumed would exist (because it
// was in the directory of an umbrella header, for instance), but no
// actual module exists for it (because the umbrella header is
// incomplete). Treat this as a textual inclusion.
SuggestedModule = ModuleMap::KnownHeader();
} else {
// We hit an error processing the import. Bail out.
if (hadModuleLoaderFatalFailure()) {
// With a fatal failure in the module loader, we abort parsing.
Token &Result = IncludeTok;
if (CurLexer) {
Result.startToken();
CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd, tok::eof);
CurLexer->cutOffLexing();
} else {
assert(CurPTHLexer && "#include but no current lexer set!");
CurPTHLexer->getEOF(Result);
}
}
return;
}
}
if (Callbacks) {
// Notify the callback object that we've seen an inclusion directive.
Callbacks->InclusionDirective(
HashLoc, IncludeTok,
LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled,
FilenameRange, File, SearchPath, RelativePath,
ShouldEnter ? nullptr : SuggestedModule.getModule());
}
if (!File)
return;
// The #included file will be considered to be a system header if either it is
// in a system include directory, or if the #includer is a system include
// header.
SrcMgr::CharacteristicKind FileCharacter =
std::max(HeaderInfo.getFileDirFlavor(File),
SourceMgr.getFileCharacteristic(FilenameTok.getLocation()));
// FIXME: If we have a suggested module, and we've already visited this file,
// don't bother entering it again. We know it has no further effect.
// Ask HeaderInfo if we should enter this #include file. If not, #including
// this file will have no effect.
if (ShouldEnter &&
!HeaderInfo.ShouldEnterIncludeFile(*this, File, isImport)) {
ShouldEnter = false;
if (Callbacks)
Callbacks->FileSkipped(*File, FilenameTok, FileCharacter);
}
// If we don't need to enter the file, stop now.
if (!ShouldEnter) {
// If this is a module import, make it visible if needed.
if (auto *M = SuggestedModule.getModule()) {
makeModuleVisible(M, HashLoc);
if (IncludeTok.getIdentifierInfo()->getPPKeywordID() !=
tok::pp___include_macros)
EnterAnnotationToken(*this, HashLoc, End, tok::annot_module_include, M);
}
return;
}
// Look up the file, create a File ID for it.
SourceLocation IncludePos = End;
// If the filename string was the result of macro expansions, set the include
// position on the file where it will be included and after the expansions.
if (IncludePos.isMacroID())
IncludePos = SourceMgr.getExpansionRange(IncludePos).second;
FileID FID = SourceMgr.createFileID(File, IncludePos, FileCharacter);
assert(!FID.isInvalid() && "Expected valid file ID");
// If all is good, enter the new file!
if (EnterSourceFile(FID, CurDir, FilenameTok.getLocation()))
return;
// Determine if we're switching to building a new submodule, and which one.
if (auto *M = SuggestedModule.getModule()) {
assert(!CurSubmodule && "should not have marked this as a module yet");
CurSubmodule = M;
// Let the macro handling code know that any future macros are within
// the new submodule.
EnterSubmodule(M, HashLoc);
// Let the parser know that any future declarations are within the new
// submodule.
// FIXME: There's no point doing this if we're handling a #__include_macros
// directive.
EnterAnnotationToken(*this, HashLoc, End, tok::annot_module_begin, M);
}
}
/// HandleIncludeNextDirective - Implements \#include_next.
///
void Preprocessor::HandleIncludeNextDirective(SourceLocation HashLoc,
Token &IncludeNextTok) {
Diag(IncludeNextTok, diag::ext_pp_include_next_directive);
// #include_next is like #include, except that we start searching after
// the current found directory. If we can't do this, issue a
// diagnostic.
const DirectoryLookup *Lookup = CurDirLookup;
const FileEntry *LookupFromFile = nullptr;
if (isInPrimaryFile()) {
Lookup = nullptr;
Diag(IncludeNextTok, diag::pp_include_next_in_primary);
} else if (CurSubmodule) {
// Start looking up in the directory *after* the one in which the current
// file would be found, if any.
assert(CurPPLexer && "#include_next directive in macro?");
LookupFromFile = CurPPLexer->getFileEntry();
Lookup = nullptr;
} else if (!Lookup) {
Diag(IncludeNextTok, diag::pp_include_next_absolute_path);
} else {
// Start looking up in the next directory.
++Lookup;
}
return HandleIncludeDirective(HashLoc, IncludeNextTok, Lookup,
LookupFromFile);
}
/// HandleMicrosoftImportDirective - Implements \#import for Microsoft Mode
void Preprocessor::HandleMicrosoftImportDirective(Token &Tok) {
// The Microsoft #import directive takes a type library and generates header
// files from it, and includes those. This is beyond the scope of what clang
// does, so we ignore it and error out. However, #import can optionally have
// trailing attributes that span multiple lines. We're going to eat those
// so we can continue processing from there.
Diag(Tok, diag::err_pp_import_directive_ms );
// Read tokens until we get to the end of the directive. Note that the
// directive can be split over multiple lines using the backslash character.
DiscardUntilEndOfDirective();
}
/// HandleImportDirective - Implements \#import.
///
void Preprocessor::HandleImportDirective(SourceLocation HashLoc,
Token &ImportTok) {
if (!LangOpts.ObjC1) { // #import is standard for ObjC.
if (LangOpts.MSVCCompat)
return HandleMicrosoftImportDirective(ImportTok);
Diag(ImportTok, diag::ext_pp_import_directive);
}
return HandleIncludeDirective(HashLoc, ImportTok, nullptr, nullptr, true);
}
/// HandleIncludeMacrosDirective - The -imacros command line option turns into a
/// pseudo directive in the predefines buffer. This handles it by sucking all
/// tokens through the preprocessor and discarding them (only keeping the side
/// effects on the preprocessor).
void Preprocessor::HandleIncludeMacrosDirective(SourceLocation HashLoc,
Token &IncludeMacrosTok) {
// This directive should only occur in the predefines buffer. If not, emit an
// error and reject it.
SourceLocation Loc = IncludeMacrosTok.getLocation();
if (strcmp(SourceMgr.getBufferName(Loc), "<built-in>") != 0) {
Diag(IncludeMacrosTok.getLocation(),
diag::pp_include_macros_out_of_predefines);
DiscardUntilEndOfDirective();
return;
}
// Treat this as a normal #include for checking purposes. If this is
// successful, it will push a new lexer onto the include stack.
HandleIncludeDirective(HashLoc, IncludeMacrosTok);
Token TmpTok;
do {
Lex(TmpTok);
assert(TmpTok.isNot(tok::eof) && "Didn't find end of -imacros!");
} while (TmpTok.isNot(tok::hashhash));
}
//===----------------------------------------------------------------------===//
// Preprocessor Macro Directive Handling.
//===----------------------------------------------------------------------===//
/// ReadMacroDefinitionArgList - The ( starting an argument list of a macro
/// definition has just been read. Lex the rest of the arguments and the
/// closing ), updating MI with what we learn. Return true if an error occurs
/// parsing the arg list.
bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI, Token &Tok) {
SmallVector<IdentifierInfo*, 32> Arguments;
while (1) {
LexUnexpandedToken(Tok);
switch (Tok.getKind()) {
case tok::r_paren:
// Found the end of the argument list.
if (Arguments.empty()) // #define FOO()
return false;
// Otherwise we have #define FOO(A,)
Diag(Tok, diag::err_pp_expected_ident_in_arg_list);
return true;
case tok::ellipsis: // #define X(... -> C99 varargs
if (!LangOpts.C99)
Diag(Tok, LangOpts.CPlusPlus11 ?
diag::warn_cxx98_compat_variadic_macro :
diag::ext_variadic_macro);
// OpenCL v1.2 s6.9.e: variadic macros are not supported.
if (LangOpts.OpenCL) {
Diag(Tok, diag::err_pp_opencl_variadic_macros);
return true;
}
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
if (Tok.isNot(tok::r_paren)) {
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
}
// Add the __VA_ARGS__ identifier as an argument.
Arguments.push_back(Ident__VA_ARGS__);
MI->setIsC99Varargs();
MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
return false;
case tok::eod: // #define X(
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
default:
// Handle keywords and identifiers here to accept things like
// #define Foo(for) for.
IdentifierInfo *II = Tok.getIdentifierInfo();
if (!II) {
// #define X(1
Diag(Tok, diag::err_pp_invalid_tok_in_arg_list);
return true;
}
// If this is already used as an argument, it is used multiple times (e.g.
// #define X(A,A.
if (std::find(Arguments.begin(), Arguments.end(), II) !=
Arguments.end()) { // C99 6.10.3p6
Diag(Tok, diag::err_pp_duplicate_name_in_arg_list) << II;
return true;
}
// Add the argument to the macro info.
Arguments.push_back(II);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
switch (Tok.getKind()) {
default: // #define X(A B
Diag(Tok, diag::err_pp_expected_comma_in_arg_list);
return true;
case tok::r_paren: // #define X(A)
MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
return false;
case tok::comma: // #define X(A,
break;
case tok::ellipsis: // #define X(A... -> GCC extension
// Diagnose extension.
Diag(Tok, diag::ext_named_variadic_macro);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
if (Tok.isNot(tok::r_paren)) {
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
}
MI->setIsGNUVarargs();
MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
return false;
}
}
}
}
static bool isConfigurationPattern(Token &MacroName, MacroInfo *MI,
const LangOptions &LOptions) {
if (MI->getNumTokens() == 1) {
const Token &Value = MI->getReplacementToken(0);
// Macro that is identity, like '#define inline inline' is a valid pattern.
if (MacroName.getKind() == Value.getKind())
return true;
// Macro that maps a keyword to the same keyword decorated with leading/
// trailing underscores is a valid pattern:
// #define inline __inline
// #define inline __inline__
// #define inline _inline (in MS compatibility mode)
StringRef MacroText = MacroName.getIdentifierInfo()->getName();
if (IdentifierInfo *II = Value.getIdentifierInfo()) {
if (!II->isKeyword(LOptions))
return false;
StringRef ValueText = II->getName();
StringRef TrimmedValue = ValueText;
if (!ValueText.startswith("__")) {
if (ValueText.startswith("_"))
TrimmedValue = TrimmedValue.drop_front(1);
else
return false;
} else {
TrimmedValue = TrimmedValue.drop_front(2);
if (TrimmedValue.endswith("__"))
TrimmedValue = TrimmedValue.drop_back(2);
}
return TrimmedValue.equals(MacroText);
} else {
return false;
}
}
// #define inline
if ((MacroName.is(tok::kw_extern) || MacroName.is(tok::kw_inline) ||
MacroName.is(tok::kw_static) || MacroName.is(tok::kw_const)) &&
MI->getNumTokens() == 0) {
return true;
}
return false;
}
/// HandleDefineDirective - Implements \#define. This consumes the entire macro
/// line then lets the caller lex the next real token.
void Preprocessor::HandleDefineDirective(Token &DefineTok,
bool ImmediatelyAfterHeaderGuard) {
++NumDefined;
Token MacroNameTok;
bool MacroShadowsKeyword;
ReadMacroName(MacroNameTok, MU_Define, &MacroShadowsKeyword);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.is(tok::eod))
return;
Token LastTok = MacroNameTok;
// If we are supposed to keep comments in #defines, reenable comment saving
// mode.
if (CurLexer) CurLexer->SetCommentRetentionState(KeepMacroComments);
// Create the new macro.
MacroInfo *MI = AllocateMacroInfo(MacroNameTok.getLocation());
Token Tok;
LexUnexpandedToken(Tok);
// If this is a function-like macro definition, parse the argument list,
// marking each of the identifiers as being used as macro arguments. Also,
// check other constraints on the first token of the macro body.
if (Tok.is(tok::eod)) {
if (ImmediatelyAfterHeaderGuard) {
// Save this macro information since it may part of a header guard.
CurPPLexer->MIOpt.SetDefinedMacro(MacroNameTok.getIdentifierInfo(),
MacroNameTok.getLocation());
}
// If there is no body to this macro, we have no special handling here.
} else if (Tok.hasLeadingSpace()) {
// This is a normal token with leading space. Clear the leading space
// marker on the first token to get proper expansion.
Tok.clearFlag(Token::LeadingSpace);
} else if (Tok.is(tok::l_paren)) {
// This is a function-like macro definition. Read the argument list.
MI->setIsFunctionLike();
if (ReadMacroDefinitionArgList(MI, LastTok)) {
// Throw away the rest of the line.
if (CurPPLexer->ParsingPreprocessorDirective)
DiscardUntilEndOfDirective();
return;
}
// If this is a definition of a variadic C99 function-like macro, not using
// the GNU named varargs extension, enabled __VA_ARGS__.
// "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
// This gets unpoisoned where it is allowed.
assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned!");
if (MI->isC99Varargs())
Ident__VA_ARGS__->setIsPoisoned(false);
// Read the first token after the arg list for down below.
LexUnexpandedToken(Tok);
} else if (LangOpts.C99 || LangOpts.CPlusPlus11) {
// C99 requires whitespace between the macro definition and the body. Emit
// a diagnostic for something like "#define X+".
Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name);
} else {
// C90 6.8 TC1 says: "In the definition of an object-like macro, if the
// first character of a replacement list is not a character required by
// subclause 5.2.1, then there shall be white-space separation between the
// identifier and the replacement list.". 5.2.1 lists this set:
// "A-Za-z0-9!"#%&'()*+,_./:;<=>?[\]^_{|}~" as well as whitespace, which
// is irrelevant here.
bool isInvalid = false;
if (Tok.is(tok::at)) // @ is not in the list above.
isInvalid = true;
else if (Tok.is(tok::unknown)) {
// If we have an unknown token, it is something strange like "`". Since
// all of valid characters would have lexed into a single character
// token of some sort, we know this is not a valid case.
isInvalid = true;
}
if (isInvalid)
Diag(Tok, diag::ext_missing_whitespace_after_macro_name);
else
Diag(Tok, diag::warn_missing_whitespace_after_macro_name);
}
if (!Tok.is(tok::eod))
LastTok = Tok;
// Read the rest of the macro body.
if (MI->isObjectLike()) {
// Object-like macros are very simple, just read their body.
while (Tok.isNot(tok::eod)) {
LastTok = Tok;
MI->AddTokenToBody(Tok);
// Get the next token of the macro.
LexUnexpandedToken(Tok);
}
} else {
// Otherwise, read the body of a function-like macro. While we are at it,
// check C99 6.10.3.2p1: ensure that # operators are followed by macro
// parameters in function-like macro expansions.
while (Tok.isNot(tok::eod)) {
LastTok = Tok;
if (Tok.isNot(tok::hash) && Tok.isNot(tok::hashhash)) {
MI->AddTokenToBody(Tok);
// Get the next token of the macro.
LexUnexpandedToken(Tok);
continue;
}
// If we're in -traditional mode, then we should ignore stringification
// and token pasting. Mark the tokens as unknown so as not to confuse
// things.
if (getLangOpts().TraditionalCPP) {
Tok.setKind(tok::unknown);
MI->AddTokenToBody(Tok);
// Get the next token of the macro.
LexUnexpandedToken(Tok);
continue;
}
if (Tok.is(tok::hashhash)) {
// If we see token pasting, check if it looks like the gcc comma
// pasting extension. We'll use this information to suppress
// diagnostics later on.
// Get the next token of the macro.
LexUnexpandedToken(Tok);
if (Tok.is(tok::eod)) {
MI->AddTokenToBody(LastTok);
break;
}
unsigned NumTokens = MI->getNumTokens();
if (NumTokens && Tok.getIdentifierInfo() == Ident__VA_ARGS__ &&
MI->getReplacementToken(NumTokens-1).is(tok::comma))
MI->setHasCommaPasting();
// Things look ok, add the '##' token to the macro.
MI->AddTokenToBody(LastTok);
continue;
}
// Get the next token of the macro.
LexUnexpandedToken(Tok);
// Check for a valid macro arg identifier.
if (Tok.getIdentifierInfo() == nullptr ||
MI->getArgumentNum(Tok.getIdentifierInfo()) == -1) {
// If this is assembler-with-cpp mode, we accept random gibberish after
// the '#' because '#' is often a comment character. However, change
// the kind of the token to tok::unknown so that the preprocessor isn't
// confused.
if (getLangOpts().AsmPreprocessor && Tok.isNot(tok::eod)) {
LastTok.setKind(tok::unknown);
MI->AddTokenToBody(LastTok);
continue;
} else {
Diag(Tok, diag::err_pp_stringize_not_parameter);
// Disable __VA_ARGS__ again.
Ident__VA_ARGS__->setIsPoisoned(true);
return;
}
}
// Things look ok, add the '#' and param name tokens to the macro.
MI->AddTokenToBody(LastTok);
MI->AddTokenToBody(Tok);
LastTok = Tok;
// Get the next token of the macro.
LexUnexpandedToken(Tok);
}
}
if (MacroShadowsKeyword &&
!isConfigurationPattern(MacroNameTok, MI, getLangOpts())) {
Diag(MacroNameTok, diag::warn_pp_macro_hides_keyword);
}
// Disable __VA_ARGS__ again.
Ident__VA_ARGS__->setIsPoisoned(true);
// Check that there is no paste (##) operator at the beginning or end of the
// replacement list.
unsigned NumTokens = MI->getNumTokens();
if (NumTokens != 0) {
if (MI->getReplacementToken(0).is(tok::hashhash)) {
Diag(MI->getReplacementToken(0), diag::err_paste_at_start);
return;
}
if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) {
Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end);
return;
}
}
MI->setDefinitionEndLoc(LastTok.getLocation());
// Finally, if this identifier already had a macro defined for it, verify that
// the macro bodies are identical, and issue diagnostics if they are not.
if (const MacroInfo *OtherMI=getMacroInfo(MacroNameTok.getIdentifierInfo())) {
// It is very common for system headers to have tons of macro redefinitions
// and for warnings to be disabled in system headers. If this is the case,
// then don't bother calling MacroInfo::isIdenticalTo.
if (!getDiagnostics().getSuppressSystemWarnings() ||
!SourceMgr.isInSystemHeader(DefineTok.getLocation())) {
if (!OtherMI->isUsed() && OtherMI->isWarnIfUnused())
Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used);
// Warn if defining "__LINE__" and other builtins, per C99 6.10.8/4 and
// C++ [cpp.predefined]p4, but allow it as an extension.
if (OtherMI->isBuiltinMacro())
Diag(MacroNameTok, diag::ext_pp_redef_builtin_macro);
// Macros must be identical. This means all tokens and whitespace
// separation must be the same. C99 6.10.3p2.
else if (!OtherMI->isAllowRedefinitionsWithoutWarning() &&
!MI->isIdenticalTo(*OtherMI, *this, /*Syntactic=*/LangOpts.MicrosoftExt)) {
Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef)
<< MacroNameTok.getIdentifierInfo();
Diag(OtherMI->getDefinitionLoc(), diag::note_previous_definition);
}
}
if (OtherMI->isWarnIfUnused())
WarnUnusedMacroLocs.erase(OtherMI->getDefinitionLoc());
}
DefMacroDirective *MD =
appendDefMacroDirective(MacroNameTok.getIdentifierInfo(), MI);
assert(!MI->isUsed());
// If we need warning for not using the macro, add its location in the
// warn-because-unused-macro set. If it gets used it will be removed from set.
if (getSourceManager().isInMainFile(MI->getDefinitionLoc()) &&
!Diags->isIgnored(diag::pp_macro_not_used, MI->getDefinitionLoc())) {
MI->setIsWarnIfUnused(true);
WarnUnusedMacroLocs.insert(MI->getDefinitionLoc());
}
// If the callbacks want to know, tell them about the macro definition.
if (Callbacks)
Callbacks->MacroDefined(MacroNameTok, MD);
}
/// HandleUndefDirective - Implements \#undef.
///
void Preprocessor::HandleUndefDirective(Token &UndefTok) {
++NumUndefined;
Token MacroNameTok;
ReadMacroName(MacroNameTok, MU_Undef);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.is(tok::eod))
return;
// Check to see if this is the last token on the #undef line.
CheckEndOfDirective("undef");
// Okay, we have a valid identifier to undef.
auto *II = MacroNameTok.getIdentifierInfo();
auto MD = getMacroDefinition(II);
// If the callbacks want to know, tell them about the macro #undef.
// Note: no matter if the macro was defined or not.
if (Callbacks)
Callbacks->MacroUndefined(MacroNameTok, MD);
// If the macro is not defined, this is a noop undef, just return.
const MacroInfo *MI = MD.getMacroInfo();
if (!MI)
return;
if (!MI->isUsed() && MI->isWarnIfUnused())
Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used);
if (MI->isWarnIfUnused())
WarnUnusedMacroLocs.erase(MI->getDefinitionLoc());
appendMacroDirective(MacroNameTok.getIdentifierInfo(),
AllocateUndefMacroDirective(MacroNameTok.getLocation()));
}
//===----------------------------------------------------------------------===//
// Preprocessor Conditional Directive Handling.
//===----------------------------------------------------------------------===//
/// HandleIfdefDirective - Implements the \#ifdef/\#ifndef directive. isIfndef
/// is true when this is a \#ifndef directive. ReadAnyTokensBeforeDirective is
/// true if any tokens have been returned or pp-directives activated before this
/// \#ifndef has been lexed.
///
void Preprocessor::HandleIfdefDirective(Token &Result, bool isIfndef,
bool ReadAnyTokensBeforeDirective) {
++NumIf;
Token DirectiveTok = Result;
Token MacroNameTok;
ReadMacroName(MacroNameTok);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.is(tok::eod)) {
// Skip code until we get to #endif. This helps with recovery by not
// emitting an error when the #endif is reached.
SkipExcludedConditionalBlock(DirectiveTok.getLocation(),
/*Foundnonskip*/false, /*FoundElse*/false);
return;
}
// Check to see if this is the last token on the #if[n]def line.
CheckEndOfDirective(isIfndef ? "ifndef" : "ifdef");
IdentifierInfo *MII = MacroNameTok.getIdentifierInfo();
auto MD = getMacroDefinition(MII);
MacroInfo *MI = MD.getMacroInfo();
if (CurPPLexer->getConditionalStackDepth() == 0) {
// If the start of a top-level #ifdef and if the macro is not defined,
// inform MIOpt that this might be the start of a proper include guard.
// Otherwise it is some other form of unknown conditional which we can't
// handle.
if (!ReadAnyTokensBeforeDirective && !MI) {
assert(isIfndef && "#ifdef shouldn't reach here");
CurPPLexer->MIOpt.EnterTopLevelIfndef(MII, MacroNameTok.getLocation());
} else
CurPPLexer->MIOpt.EnterTopLevelConditional();
}
// If there is a macro, process it.
if (MI) // Mark it used.
markMacroAsUsed(MI);
if (Callbacks) {
if (isIfndef)
Callbacks->Ifndef(DirectiveTok.getLocation(), MacroNameTok, MD);
else
Callbacks->Ifdef(DirectiveTok.getLocation(), MacroNameTok, MD);
}
// Should we include the stuff contained by this directive?
if (!MI == isIfndef) {
// Yes, remember that we are inside a conditional, then lex the next token.
CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(),
/*wasskip*/false, /*foundnonskip*/true,
/*foundelse*/false);
} else {
// No, skip the contents of this block.
SkipExcludedConditionalBlock(DirectiveTok.getLocation(),
/*Foundnonskip*/false,
/*FoundElse*/false);
}
}
/// HandleIfDirective - Implements the \#if directive.
///
void Preprocessor::HandleIfDirective(Token &IfToken,
bool ReadAnyTokensBeforeDirective) {
++NumIf;
// Parse and evaluate the conditional expression.
IdentifierInfo *IfNDefMacro = nullptr;
const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation();
const bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro);
const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation();
// If this condition is equivalent to #ifndef X, and if this is the first
// directive seen, handle it for the multiple-include optimization.
if (CurPPLexer->getConditionalStackDepth() == 0) {
if (!ReadAnyTokensBeforeDirective && IfNDefMacro && ConditionalTrue)
// FIXME: Pass in the location of the macro name, not the 'if' token.
CurPPLexer->MIOpt.EnterTopLevelIfndef(IfNDefMacro, IfToken.getLocation());
else
CurPPLexer->MIOpt.EnterTopLevelConditional();
}
if (Callbacks)
Callbacks->If(IfToken.getLocation(),
SourceRange(ConditionalBegin, ConditionalEnd),
(ConditionalTrue ? PPCallbacks::CVK_True : PPCallbacks::CVK_False));
// Should we include the stuff contained by this directive?
if (ConditionalTrue) {
// Yes, remember that we are inside a conditional, then lex the next token.
CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false,
/*foundnonskip*/true, /*foundelse*/false);
} else {
// No, skip the contents of this block.
SkipExcludedConditionalBlock(IfToken.getLocation(), /*Foundnonskip*/false,
/*FoundElse*/false);
}
}
/// HandleEndifDirective - Implements the \#endif directive.
///
void Preprocessor::HandleEndifDirective(Token &EndifToken) {
++NumEndif;
// Check that this is the whole directive.
CheckEndOfDirective("endif");
PPConditionalInfo CondInfo;
if (CurPPLexer->popConditionalLevel(CondInfo)) {
// No conditionals on the stack: this is an #endif without an #if.
Diag(EndifToken, diag::err_pp_endif_without_if);
return;
}
// If this the end of a top-level #endif, inform MIOpt.
if (CurPPLexer->getConditionalStackDepth() == 0)
CurPPLexer->MIOpt.ExitTopLevelConditional();
assert(!CondInfo.WasSkipping && !CurPPLexer->LexingRawMode &&
"This code should only be reachable in the non-skipping case!");
if (Callbacks)
Callbacks->Endif(EndifToken.getLocation(), CondInfo.IfLoc);
}
/// HandleElseDirective - Implements the \#else directive.
///
void Preprocessor::HandleElseDirective(Token &Result) {
++NumElse;
// #else directive in a non-skipping conditional... start skipping.
CheckEndOfDirective("else");
PPConditionalInfo CI;
if (CurPPLexer->popConditionalLevel(CI)) {
Diag(Result, diag::pp_err_else_without_if);
return;
}
// If this is a top-level #else, inform the MIOpt.
if (CurPPLexer->getConditionalStackDepth() == 0)
CurPPLexer->MIOpt.EnterTopLevelConditional();
// If this is a #else with a #else before it, report the error.
if (CI.FoundElse) Diag(Result, diag::pp_err_else_after_else);
if (Callbacks)
Callbacks->Else(Result.getLocation(), CI.IfLoc);
// Finally, skip the rest of the contents of this block.
SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
/*FoundElse*/true, Result.getLocation());
}
/// HandleElifDirective - Implements the \#elif directive.
///
void Preprocessor::HandleElifDirective(Token &ElifToken) {
++NumElse;
// #elif directive in a non-skipping conditional... start skipping.
// We don't care what the condition is, because we will always skip it (since
// the block immediately before it was included).
const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation();
DiscardUntilEndOfDirective();
const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation();
PPConditionalInfo CI;
if (CurPPLexer->popConditionalLevel(CI)) {
Diag(ElifToken, diag::pp_err_elif_without_if);
return;
}
// If this is a top-level #elif, inform the MIOpt.
if (CurPPLexer->getConditionalStackDepth() == 0)
CurPPLexer->MIOpt.EnterTopLevelConditional();
// If this is a #elif with a #else before it, report the error.
if (CI.FoundElse) Diag(ElifToken, diag::pp_err_elif_after_else);
if (Callbacks)
Callbacks->Elif(ElifToken.getLocation(),
SourceRange(ConditionalBegin, ConditionalEnd),
PPCallbacks::CVK_NotEvaluated, CI.IfLoc);
// Finally, skip the rest of the contents of this block.
SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
/*FoundElse*/CI.FoundElse,
ElifToken.getLocation());
}
Reference in New Issue View Git Blame Copy Permalink