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llvm-project/clang/lib/Lex/PPDirectives.cpp

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//===--- 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/LiteralSupport.h"
#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/MacroInfo.h"
#include "clang/Lex/LexDiagnostic.h"
#include "clang/Lex/CodeCompletionHandler.h"
#include "clang/Lex/Pragma.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "llvm/ADT/APInt.h"
using namespace clang;
//===----------------------------------------------------------------------===//
// Utility Methods for Preprocessor Directive Handling.
//===----------------------------------------------------------------------===//
MacroInfo *Preprocessor::AllocateMacroInfo() {
MacroInfoChain *MIChain;
if (MICache) {
MIChain = MICache;
MICache = MICache->Next;
}
else {
MIChain = BP.Allocate<MacroInfoChain>();
}
MIChain->Next = MIChainHead;
MIChain->Prev = 0;
if (MIChainHead)
MIChainHead->Prev = MIChain;
MIChainHead = MIChain;
return &(MIChain->MI);
}
MacroInfo *Preprocessor::AllocateMacroInfo(SourceLocation L) {
MacroInfo *MI = AllocateMacroInfo();
new (MI) MacroInfo(L);
return MI;
}
MacroInfo *Preprocessor::CloneMacroInfo(const MacroInfo &MacroToClone) {
MacroInfo *MI = AllocateMacroInfo();
new (MI) MacroInfo(MacroToClone, BP);
return MI;
}
/// ReleaseMacroInfo - Release the specified MacroInfo. This memory will
/// be reused for allocating new MacroInfo objects.
void Preprocessor::ReleaseMacroInfo(MacroInfo *MI) {
MacroInfoChain *MIChain = (MacroInfoChain*) MI;
if (MacroInfoChain *Prev = MIChain->Prev) {
MacroInfoChain *Next = MIChain->Next;
Prev->Next = Next;
if (Next)
Next->Prev = Prev;
}
else {
assert(MIChainHead == MIChain);
MIChainHead = MIChain->Next;
MIChainHead->Prev = 0;
}
MIChain->Next = MICache;
MICache = MIChain;
MI->Destroy();
}
/// DiscardUntilEndOfDirective - 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));
}
/// ReadMacroName - 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. isDefineUndef is 1 if
/// this is due to a a #define, 2 if #undef directive, 0 if it is something
/// else (e.g. #ifdef).
void Preprocessor::ReadMacroName(Token &MacroNameTok, char isDefineUndef) {
// Read the token, don't allow macro expansion on it.
LexUnexpandedToken(MacroNameTok);
if (MacroNameTok.is(tok::code_completion)) {
if (CodeComplete)
CodeComplete->CodeCompleteMacroName(isDefineUndef == 1);
LexUnexpandedToken(MacroNameTok);
return;
}
// Missing macro name?
if (MacroNameTok.is(tok::eod)) {
Diag(MacroNameTok, diag::err_pp_missing_macro_name);
return;
}
IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
if (II == 0) {
bool Invalid = false;
std::string Spelling = getSpelling(MacroNameTok, &Invalid);
if (Invalid)
return;
const IdentifierInfo &Info = Identifiers.get(Spelling);
if (Info.isCPlusPlusOperatorKeyword())
// 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::eod.
MacroNameTok.setKind(tok::eod);
return DiscardUntilEndOfDirective();
}
/// CheckEndOfDirective - 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 ((Features.GNUMode || Features.C99 || Features.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) {
++NumSkipped;
assert(CurTokenLexer == 0 && 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();
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 (!isCodeCompletionFile(Tok.getLocation()))
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->SetCommentRetentionState(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->SetCommentRetentionState(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 = Tok.getRawIdentifierData();
char FirstChar = RawCharData[0];
if (FirstChar >= 'a' && FirstChar <= 'z' &&
FirstChar != 'i' && FirstChar != 'e') {
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->SetCommentRetentionState(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.
char DirectiveBuf[20];
llvm::StringRef Directive;
if (!Tok.needsCleaning() && Tok.getLength() < 20) {
Directive = llvm::StringRef(RawCharData, Tok.getLength());
} else {
std::string DirectiveStr = getSpelling(Tok);
unsigned IdLen = DirectiveStr.size();
if (IdLen >= 20) {
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->SetCommentRetentionState(KeepComments);
continue;
}
memcpy(DirectiveBuf, &DirectiveStr[0], IdLen);
Directive = llvm::StringRef(DirectiveBuf, IdLen);
}
if (Directive.startswith("if")) {
llvm::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);
if (Callbacks)
Callbacks->Endif();
}
} else if (Directive[0] == 'e') {
llvm::StringRef Sub = Directive.substr(1);
if (Sub == "ndif") { // "endif"
CheckEndOfDirective("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)
break;
} 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.
DiscardUntilEndOfDirective(); // C99 6.10p4.
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 (Callbacks)
Callbacks->Else();
// 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 (Sub == "lif") { // "elif".
PPConditionalInfo &CondInfo = CurPPLexer->peekConditionalLevel();
bool ShouldEnter;
const SourceLocation ConditionalBegin = CurPPLexer->getSourceLocation();
// 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(CurPPLexer->LexingRawMode && "We have to be skipping here!");
CurPPLexer->LexingRawMode = false;
IdentifierInfo *IfNDefMacro = 0;
ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro);
CurPPLexer->LexingRawMode = true;
}
const SourceLocation ConditionalEnd = CurPPLexer->getSourceLocation();
// 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 (Callbacks)
Callbacks->Elif(SourceRange(ConditionalBegin, ConditionalEnd));
// If this condition is true, enter it!
if (ShouldEnter) {
CondInfo.FoundNonSkip = true;
break;
}
}
}
CurPPLexer->ParsingPreprocessorDirective = false;
// Restore comment saving mode.
if (CurLexer) CurLexer->SetCommentRetentionState(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.
CurPPLexer->LexingRawMode = false;
}
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 = 0;
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;
}
}
/// 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(
llvm::StringRef Filename,
bool isAngled,
const DirectoryLookup *FromDir,
const DirectoryLookup *&CurDir,
llvm::SmallVectorImpl<char> *RawPath) {
// 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) {
FileID FID = getCurrentFileLexer()->getFileID();
CurFileEnt = SourceMgr.getFileEntryForID(FID);
// If there is no file entry associated with this file, it must be the
// predefines buffer. Any other file is not lexed with a normal lexer, so
// it won't be scanned for preprocessor directives. If we have the
// predefines buffer, resolve #include references (which come from the
// -include command line argument) as if they came from the main file, this
// affects file lookup etc.
if (CurFileEnt == 0) {
FID = SourceMgr.getMainFileID();
CurFileEnt = SourceMgr.getFileEntryForID(FID);
}
}
// Do a standard file entry lookup.
CurDir = CurDirLookup;
const FileEntry *FE = HeaderInfo.LookupFile(
Filename, isAngled, FromDir, CurDir, CurFileEnt, RawPath);
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 (IsFileLexer()) {
if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID())))
if ((FE = HeaderInfo.LookupSubframeworkHeader(Filename, CurFileEnt,
RawPath)))
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,
RawPath)))
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
// EOD token (which terminates the directive).
CurPPLexer->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 =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 non-portable behavior, emit a diagnostic.
if (InMacroArgs)
Diag(Result, diag::ext_embedded_directive);
TryAgain:
switch (Result.getKind()) {
case tok::eod:
return; // null directive.
case tok::comment:
// Handle stuff like "# /*foo*/ define X" in -E -C mode.
LexUnexpandedToken(Result);
goto TryAgain;
case tok::code_completion:
if (CodeComplete)
CodeComplete->CodeCompleteDirective(
CurPPLexer->getConditionalStackDepth() > 0);
return;
case tok::numeric_constant: // # 7 GNU line marker directive.
if (getLangOptions().AsmPreprocessor)
break; // # 4 is not a preprocessor directive in .S files.
return HandleDigitDirective(Result);
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:
// 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);
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(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;
}
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 (getLangOptions().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) {
if (DigitTok.isNot(tok::numeric_constant)) {
PP.Diag(DigitTok, DiagID);
if (DigitTok.isNot(tok::eod))
PP.DiscardUntilEndOfDirective();
return true;
}
llvm::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) {
if (!isdigit(DigitTokBegin[i])) {
PP.Diag(PP.AdvanceToTokenCharacter(DigitTok.getLocation(), i),
diag::err_pp_line_digit_sequence);
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;
}
// Reject 0, this is needed both by #line numbers and flags.
if (Val == 0) {
PP.Diag(DigitTok, DiagID);
PP.DiscardUntilEndOfDirective();
return true;
}
if (DigitTokBegin[0] == '0')
PP.Diag(DigitTok.getLocation(), diag::warn_pp_line_decimal);
return false;
}
/// HandleLineDirective - Handle #line directive: C99 6.10.4. The two
/// acceptable forms are:
/// # line digit-sequence
/// # line digit-sequence "s-char-sequence"
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;
// 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 = Features.C99 ? 2147483648U : 32768U;
if (LineNo >= LineLimit)
Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit;
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);
DiscardUntilEndOfDirective();
return;
} else {
// Parse and validate the string, converting it into a unique ID.
StringLiteralParser Literal(&StrTok, 1, *this);
assert(!Literal.AnyWide && "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(),
Literal.GetStringLength());
// 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.getDecomposedInstantiationLoc(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.getDecomposedInstantiationLoc(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))
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 {
// Parse and validate the string, converting it into a unique ID.
StringLiteralParser Literal(&StrTok, 1, *this);
assert(!Literal.AnyWide && "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(),
Literal.GetStringLength());
// 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.
std::string Message = CurLexer->ReadToEndOfLine();
if (isWarning)
Diag(Tok, diag::pp_hash_warning) << Message;
else
Diag(Tok, diag::err_pp_hash_error) << 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)) {
Diag(StrTok, diag::err_pp_malformed_ident);
if (StrTok.isNot(tok::eod))
DiscardUntilEndOfDirective();
return;
}
// 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);
}
}
//===----------------------------------------------------------------------===//
// 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,
llvm::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 = llvm::StringRef();
return true;
}
isAngled = true;
} else if (Buffer[0] == '"') {
if (Buffer.back() != '"') {
Diag(Loc, diag::err_pp_expects_filename);
Buffer = llvm::StringRef();
return true;
}
isAngled = false;
} else {
Diag(Loc, diag::err_pp_expects_filename);
Buffer = llvm::StringRef();
return true;
}
// Diagnose #include "" as invalid.
if (Buffer.size() <= 2) {
Diag(Loc, diag::err_pp_empty_filename);
Buffer = llvm::StringRef();
return true;
}
// Skip the brackets.
Buffer = Buffer.substr(1, Buffer.size()-2);
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 EOD marker.
bool Preprocessor::ConcatenateIncludeName(
llvm::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)) {
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;
}
/// HandleIncludeDirective - The "#include" tokens have just been read, read the
/// file to be included from the lexer, then include it! This is a common
/// routine with functionality shared between #include, #include_next and
/// #import. LookupFrom is set when this is a #include_next directive, it
/// specifies the file to start searching from.
void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
Token &IncludeTok,
const DirectoryLookup *LookupFrom,
bool isImport) {
Token FilenameTok;
CurPPLexer->LexIncludeFilename(FilenameTok);
// Reserve a buffer to get the spelling.
llvm::SmallString<128> FilenameBuffer;
llvm::StringRef Filename;
SourceLocation End;
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();
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.str();
break;
default:
Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename);
DiscardUntilEndOfDirective();
return;
}
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;
}
// Search include directories.
const DirectoryLookup *CurDir;
llvm::SmallString<1024> RawPath;
// We get the raw path only if we have 'Callbacks' to which we later pass
// the path.
const FileEntry *File = LookupFile(
Filename, isAngled, LookupFrom, CurDir, Callbacks ? &RawPath : NULL);
if (File == 0) {
Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
return;
}
// Notify the callback object that we've seen an inclusion directive.
if (Callbacks)
Callbacks->InclusionDirective(HashLoc, IncludeTok, Filename, isAngled, File,
End, RawPath);
// The #included file will be considered to be a system header if either it is
// in a system include directory, or if the #includer is a system include
// header.
SrcMgr::CharacteristicKind FileCharacter =
std::max(HeaderInfo.getFileDirFlavor(File),
SourceMgr.getFileCharacteristic(FilenameTok.getLocation()));
// Ask HeaderInfo if we should enter this #include file. If not, #including
// this file will have no effect.
if (!HeaderInfo.ShouldEnterIncludeFile(File, isImport)) {
if (Callbacks)
Callbacks->FileSkipped(*File, FilenameTok, FileCharacter);
return;
}
// Look up the file, create a File ID for it.
FileID FID = SourceMgr.createFileID(File, FilenameTok.getLocation(),
FileCharacter);
if (FID.isInvalid()) {
Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
return;
}
// Finally, if all is good, enter the new file!
EnterSourceFile(FID, CurDir, FilenameTok.getLocation());
}
/// HandleIncludeNextDirective - Implements #include_next.
///
void Preprocessor::HandleIncludeNextDirective(SourceLocation HashLoc,
Token &IncludeNextTok) {
Diag(IncludeNextTok, diag::ext_pp_include_next_directive);
// #include_next is like #include, except that we start searching after
// the current found directory. If we can't do this, issue a
// diagnostic.
const DirectoryLookup *Lookup = CurDirLookup;
if (isInPrimaryFile()) {
Lookup = 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(HashLoc, IncludeNextTok, Lookup);
}
/// HandleImportDirective - Implements #import.
///
void Preprocessor::HandleImportDirective(SourceLocation HashLoc,
Token &ImportTok) {
if (!Features.ObjC1) // #import is standard for ObjC.
Diag(ImportTok, diag::ext_pp_import_directive);
return HandleIncludeDirective(HashLoc, ImportTok, 0, 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, 0, false);
Token TmpTok;
do {
Lex(TmpTok);
assert(TmpTok.isNot(tok::eof) && "Didn't find end of -imacros!");
} while (TmpTok.isNot(tok::hashhash));
}
//===----------------------------------------------------------------------===//
// Preprocessor Macro Directive Handling.
//===----------------------------------------------------------------------===//
/// ReadMacroDefinitionArgList - The ( starting an argument list of a macro
/// definition has just been read. Lex the rest of the arguments and the
/// closing ), updating MI with what we learn. Return true if an error occurs
/// parsing the arg list.
bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) {
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()
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[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 == 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;
return true;
}
// Add the argument to the macro info.
Arguments.push_back(II);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
switch (Tok.getKind()) {
default: // #define X(A B
Diag(Tok, diag::err_pp_expected_comma_in_arg_list);
return true;
case tok::r_paren: // #define X(A)
MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
return false;
case tok::comma: // #define X(A,
break;
case tok::ellipsis: // #define X(A... -> GCC extension
// Diagnose extension.
Diag(Tok, diag::ext_named_variadic_macro);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
if (Tok.isNot(tok::r_paren)) {
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
}
MI->setIsGNUVarargs();
MI->setArgumentList(&Arguments[0], Arguments.size(), BP);
return false;
}
}
}
}
/// HandleDefineDirective - Implements #define. This consumes the entire macro
/// line then lets the caller lex the next real token.
void Preprocessor::HandleDefineDirective(Token &DefineTok) {
++NumDefined;
Token MacroNameTok;
ReadMacroName(MacroNameTok, 1);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.is(tok::eod))
return;
Token LastTok = MacroNameTok;
// If we are supposed to keep comments in #defines, reenable comment saving
// mode.
if (CurLexer) CurLexer->SetCommentRetentionState(KeepMacroComments);
// Create the new macro.
MacroInfo *MI = AllocateMacroInfo(MacroNameTok.getLocation());
Token Tok;
LexUnexpandedToken(Tok);
// If this is a function-like macro definition, parse the argument list,
// marking each of the identifiers as being used as macro arguments. Also,
// check other constraints on the first token of the macro body.
if (Tok.is(tok::eod)) {
// If 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)) {
// Forget about MI.
ReleaseMacroInfo(MI);
// Throw away the rest of the line.
if (CurPPLexer->ParsingPreprocessorDirective)
DiscardUntilEndOfDirective();
return;
}
// If this is a definition of a variadic C99 function-like macro, not using
// the GNU named varargs extension, enabled __VA_ARGS__.
// "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
// This gets unpoisoned where it is allowed.
assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned!");
if (MI->isC99Varargs())
Ident__VA_ARGS__->setIsPoisoned(false);
// Read the first token after the arg list for down below.
LexUnexpandedToken(Tok);
} else if (Features.C99) {
// 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)) {
MI->AddTokenToBody(Tok);
// Get the next token of the macro.
LexUnexpandedToken(Tok);
continue;
}
// Get the next token of the macro.
LexUnexpandedToken(Tok);
// Check for a valid macro arg identifier.
if (Tok.getIdentifierInfo() == 0 ||
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 (getLangOptions().AsmPreprocessor && Tok.isNot(tok::eod)) {
LastTok.setKind(tok::unknown);
} else {
Diag(Tok, diag::err_pp_stringize_not_parameter);
ReleaseMacroInfo(MI);
// Disable __VA_ARGS__ again.
Ident__VA_ARGS__->setIsPoisoned(true);
return;
}
}
// Things look ok, add the '#' and param name tokens to the macro.
MI->AddTokenToBody(LastTok);
MI->AddTokenToBody(Tok);
LastTok = Tok;
// Get the next token of the macro.
LexUnexpandedToken(Tok);
}
}
// Disable __VA_ARGS__ again.
Ident__VA_ARGS__->setIsPoisoned(true);
// Check that there is no paste (##) operator at the beginning or end of the
// replacement list.
unsigned NumTokens = MI->getNumTokens();
if (NumTokens != 0) {
if (MI->getReplacementToken(0).is(tok::hashhash)) {
Diag(MI->getReplacementToken(0), diag::err_paste_at_start);
ReleaseMacroInfo(MI);
return;
}
if (MI->getReplacementToken(NumTokens-1).is(tok::hashhash)) {
Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end);
ReleaseMacroInfo(MI);
return;
}
}
MI->setDefinitionEndLoc(LastTok.getLocation());
// Finally, if this identifier already had a macro defined for it, verify that
// the macro bodies are identical and free the old definition.
if (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);
// Macros must be identical. This means all tokens and whitespace
// separation must be the same. C99 6.10.3.2.
if (!OtherMI->isAllowRedefinitionsWithoutWarning() &&
!MI->isIdenticalTo(*OtherMI, *this)) {
Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef)
<< MacroNameTok.getIdentifierInfo();
Diag(OtherMI->getDefinitionLoc(), diag::note_previous_definition);
}
}
if (OtherMI->isWarnIfUnused())
WarnUnusedMacroLocs.erase(OtherMI->getDefinitionLoc());
ReleaseMacroInfo(OtherMI);
}
setMacroInfo(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 (isInPrimaryFile() && // don't warn for include'd macros.
Diags->getDiagnosticLevel(diag::pp_macro_not_used,
MI->getDefinitionLoc()) != Diagnostic::Ignored) {
MI->setIsWarnIfUnused(true);
WarnUnusedMacroLocs.insert(MI->getDefinitionLoc());
}
// If the callbacks want to know, tell them about the macro definition.
if (Callbacks)
Callbacks->MacroDefined(MacroNameTok, 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::eod))
return;
// Check to see if this is the last token on the #undef line.
CheckEndOfDirective("undef");
// Okay, we finally have a valid identifier to undef.
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);
// If the callbacks want to know, tell them about the macro #undef.
if (Callbacks)
Callbacks->MacroUndefined(MacroNameTok, MI);
if (MI->isWarnIfUnused())
WarnUnusedMacroLocs.erase(MI->getDefinitionLoc());
// Free macro definition.
ReleaseMacroInfo(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::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();
MacroInfo *MI = getMacroInfo(MII);
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 == 0) {
assert(isIfndef && "#ifdef shouldn't reach here");
CurPPLexer->MIOpt.EnterTopLevelIFNDEF(MII);
} else
CurPPLexer->MIOpt.EnterTopLevelConditional();
}
// If there is a macro, process it.
if (MI) // Mark it used.
markMacroAsUsed(MI);
// 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);
}
if (Callbacks) {
if (isIfndef)
Callbacks->Ifndef(MacroNameTok);
else
Callbacks->Ifdef(MacroNameTok);
}
}
/// HandleIfDirective - Implements the #if directive.
///
void Preprocessor::HandleIfDirective(Token &IfToken,
bool ReadAnyTokensBeforeDirective) {
++NumIf;
// Parse and evaluate the conditional expression.
IdentifierInfo *IfNDefMacro = 0;
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)
CurPPLexer->MIOpt.EnterTopLevelIFNDEF(IfNDefMacro);
else
CurPPLexer->MIOpt.EnterTopLevelConditional();
}
// 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);
}
if (Callbacks)
Callbacks->If(SourceRange(ConditionalBegin, ConditionalEnd));
}
/// 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();
}
/// 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);
// Finally, skip the rest of the contents of this block.
SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
/*FoundElse*/true);
if (Callbacks)
Callbacks->Else();
}
/// 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);
// Finally, skip the rest of the contents of this block.
SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
/*FoundElse*/CI.FoundElse);
if (Callbacks)
Callbacks->Elif(SourceRange(ConditionalBegin, ConditionalEnd));
}
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