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//===--- PrintPreprocessedOutput.cpp - Implement the -E mode --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This code simply runs the preprocessor on the input file and prints out the
// result. This is the traditional behavior of the -E option.
//
//===----------------------------------------------------------------------===//
#include "clang/Frontend/Utils.h"
#include "clang/Basic/CharInfo.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Frontend/PreprocessorOutputOptions.h"
#include "clang/Lex/MacroInfo.h"
#include "clang/Lex/PPCallbacks.h"
#include "clang/Lex/Pragma.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Lex/TokenConcatenation.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <cstdio>
using namespace clang;
/// PrintMacroDefinition - Print a macro definition in a form that will be
/// properly accepted back as a definition.
static void PrintMacroDefinition(const IdentifierInfo &II, const MacroInfo &MI,
Preprocessor &PP, raw_ostream &OS) {
OS << "#define " << II.getName();
if (MI.isFunctionLike()) {
OS << '(';
if (!MI.arg_empty()) {
MacroInfo::arg_iterator AI = MI.arg_begin(), E = MI.arg_end();
for (; AI+1 != E; ++AI) {
OS << (*AI)->getName();
OS << ',';
}
// Last argument.
if ((*AI)->getName() == "__VA_ARGS__")
OS << "...";
else
OS << (*AI)->getName();
}
if (MI.isGNUVarargs())
OS << "..."; // #define foo(x...)
OS << ')';
}
// GCC always emits a space, even if the macro body is empty. However, do not
// want to emit two spaces if the first token has a leading space.
if (MI.tokens_empty() || !MI.tokens_begin()->hasLeadingSpace())
OS << ' ';
SmallString<128> SpellingBuffer;
for (MacroInfo::tokens_iterator I = MI.tokens_begin(), E = MI.tokens_end();
I != E; ++I) {
if (I->hasLeadingSpace())
OS << ' ';
OS << PP.getSpelling(*I, SpellingBuffer);
}
}
//===----------------------------------------------------------------------===//
// Preprocessed token printer
//===----------------------------------------------------------------------===//
namespace {
class PrintPPOutputPPCallbacks : public PPCallbacks {
Preprocessor &PP;
SourceManager &SM;
TokenConcatenation ConcatInfo;
public:
raw_ostream &OS;
private:
unsigned CurLine;
bool EmittedTokensOnThisLine;
bool EmittedDirectiveOnThisLine;
SrcMgr::CharacteristicKind FileType;
SmallString<512> CurFilename;
bool Initialized;
bool DisableLineMarkers;
bool DumpDefines;
bool UseLineDirective;
bool IsFirstFileEntered;
public:
PrintPPOutputPPCallbacks(Preprocessor &pp, raw_ostream &os,
bool lineMarkers, bool defines)
: PP(pp), SM(PP.getSourceManager()),
ConcatInfo(PP), OS(os), DisableLineMarkers(lineMarkers),
DumpDefines(defines) {
CurLine = 0;
CurFilename += "<uninit>";
EmittedTokensOnThisLine = false;
EmittedDirectiveOnThisLine = false;
FileType = SrcMgr::C_User;
Initialized = false;
IsFirstFileEntered = false;
// If we're in microsoft mode, use normal #line instead of line markers.
UseLineDirective = PP.getLangOpts().MicrosoftExt;
}
void setEmittedTokensOnThisLine() { EmittedTokensOnThisLine = true; }
bool hasEmittedTokensOnThisLine() const { return EmittedTokensOnThisLine; }
void setEmittedDirectiveOnThisLine() { EmittedDirectiveOnThisLine = true; }
bool hasEmittedDirectiveOnThisLine() const {
return EmittedDirectiveOnThisLine;
}
bool startNewLineIfNeeded(bool ShouldUpdateCurrentLine = true);
virtual void FileChanged(SourceLocation Loc, FileChangeReason Reason,
SrcMgr::CharacteristicKind FileType,
FileID PrevFID);
virtual void InclusionDirective(SourceLocation HashLoc,
const Token &IncludeTok,
StringRef FileName,
bool IsAngled,
CharSourceRange FilenameRange,
const FileEntry *File,
StringRef SearchPath,
StringRef RelativePath,
const Module *Imported);
virtual void Ident(SourceLocation Loc, const std::string &str);
virtual void PragmaCaptured(SourceLocation Loc, StringRef Str);
virtual void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
const std::string &Str);
virtual void PragmaDetectMismatch(SourceLocation Loc,
const std::string &Name,
const std::string &Value);
virtual void PragmaMessage(SourceLocation Loc, StringRef Namespace,
PragmaMessageKind Kind, StringRef Str);
virtual void PragmaDebug(SourceLocation Loc, StringRef DebugType);
virtual void PragmaDiagnosticPush(SourceLocation Loc,
StringRef Namespace);
virtual void PragmaDiagnosticPop(SourceLocation Loc,
StringRef Namespace);
virtual void PragmaDiagnostic(SourceLocation Loc, StringRef Namespace,
diag::Mapping Map, StringRef Str);
bool HandleFirstTokOnLine(Token &Tok);
/// Move to the line of the provided source location. This will
/// return true if the output stream required adjustment or if
/// the requested location is on the first line.
bool MoveToLine(SourceLocation Loc) {
PresumedLoc PLoc = SM.getPresumedLoc(Loc);
if (PLoc.isInvalid())
return false;
return MoveToLine(PLoc.getLine()) || (PLoc.getLine() == 1);
}
bool MoveToLine(unsigned LineNo);
bool AvoidConcat(const Token &PrevPrevTok, const Token &PrevTok,
const Token &Tok) {
return ConcatInfo.AvoidConcat(PrevPrevTok, PrevTok, Tok);
}
void WriteLineInfo(unsigned LineNo, const char *Extra=0, unsigned ExtraLen=0);
bool LineMarkersAreDisabled() const { return DisableLineMarkers; }
void HandleNewlinesInToken(const char *TokStr, unsigned Len);
/// MacroDefined - This hook is called whenever a macro definition is seen.
void MacroDefined(const Token &MacroNameTok, const MacroDirective *MD);
/// MacroUndefined - This hook is called whenever a macro #undef is seen.
void MacroUndefined(const Token &MacroNameTok, const MacroDirective *MD);
};
} // end anonymous namespace
void PrintPPOutputPPCallbacks::WriteLineInfo(unsigned LineNo,
const char *Extra,
unsigned ExtraLen) {
startNewLineIfNeeded(/*ShouldUpdateCurrentLine=*/false);
// Emit #line directives or GNU line markers depending on what mode we're in.
if (UseLineDirective) {
OS << "#line" << ' ' << LineNo << ' ' << '"';
OS.write_escaped(CurFilename);
OS << '"';
} else {
OS << '#' << ' ' << LineNo << ' ' << '"';
OS.write_escaped(CurFilename);
OS << '"';
if (ExtraLen)
OS.write(Extra, ExtraLen);
if (FileType == SrcMgr::C_System)
OS.write(" 3", 2);
else if (FileType == SrcMgr::C_ExternCSystem)
OS.write(" 3 4", 4);
}
OS << '\n';
}
/// MoveToLine - Move the output to the source line specified by the location
/// object. We can do this by emitting some number of \n's, or be emitting a
/// #line directive. This returns false if already at the specified line, true
/// if some newlines were emitted.
bool PrintPPOutputPPCallbacks::MoveToLine(unsigned LineNo) {
// If this line is "close enough" to the original line, just print newlines,
// otherwise print a #line directive.
if (LineNo-CurLine <= 8) {
if (LineNo-CurLine == 1)
OS << '\n';
else if (LineNo == CurLine)
return false; // Spelling line moved, but expansion line didn't.
else {
const char *NewLines = "\n\n\n\n\n\n\n\n";
OS.write(NewLines, LineNo-CurLine);
}
} else if (!DisableLineMarkers) {
// Emit a #line or line marker.
WriteLineInfo(LineNo, 0, 0);
} else {
// Okay, we're in -P mode, which turns off line markers. However, we still
// need to emit a newline between tokens on different lines.
startNewLineIfNeeded(/*ShouldUpdateCurrentLine=*/false);
}
CurLine = LineNo;
return true;
}
bool
PrintPPOutputPPCallbacks::startNewLineIfNeeded(bool ShouldUpdateCurrentLine) {
if (EmittedTokensOnThisLine || EmittedDirectiveOnThisLine) {
OS << '\n';
EmittedTokensOnThisLine = false;
EmittedDirectiveOnThisLine = false;
if (ShouldUpdateCurrentLine)
++CurLine;
return true;
}
return false;
}
/// FileChanged - Whenever the preprocessor enters or exits a #include file
/// it invokes this handler. Update our conception of the current source
/// position.
void PrintPPOutputPPCallbacks::FileChanged(SourceLocation Loc,
FileChangeReason Reason,
SrcMgr::CharacteristicKind NewFileType,
FileID PrevFID) {
// Unless we are exiting a #include, make sure to skip ahead to the line the
// #include directive was at.
SourceManager &SourceMgr = SM;
PresumedLoc UserLoc = SourceMgr.getPresumedLoc(Loc);
if (UserLoc.isInvalid())
return;
unsigned NewLine = UserLoc.getLine();
if (Reason == PPCallbacks::EnterFile) {
SourceLocation IncludeLoc = UserLoc.getIncludeLoc();
if (IncludeLoc.isValid())
MoveToLine(IncludeLoc);
} else if (Reason == PPCallbacks::SystemHeaderPragma) {
// GCC emits the # directive for this directive on the line AFTER the
// directive and emits a bunch of spaces that aren't needed. This is because
// otherwise we will emit a line marker for THIS line, which requires an
// extra blank line after the directive to avoid making all following lines
// off by one. We can do better by simply incrementing NewLine here.
NewLine += 1;
}
CurLine = NewLine;
CurFilename.clear();
CurFilename += UserLoc.getFilename();
FileType = NewFileType;
if (DisableLineMarkers) {
startNewLineIfNeeded(/*ShouldUpdateCurrentLine=*/false);
return;
}
if (!Initialized) {
WriteLineInfo(CurLine);
Initialized = true;
}
// Do not emit an enter marker for the main file (which we expect is the first
// entered file). This matches gcc, and improves compatibility with some tools
// which track the # line markers as a way to determine when the preprocessed
// output is in the context of the main file.
if (Reason == PPCallbacks::EnterFile && !IsFirstFileEntered) {
IsFirstFileEntered = true;
return;
}
switch (Reason) {
case PPCallbacks::EnterFile:
WriteLineInfo(CurLine, " 1", 2);
break;
case PPCallbacks::ExitFile:
WriteLineInfo(CurLine, " 2", 2);
break;
case PPCallbacks::SystemHeaderPragma:
case PPCallbacks::RenameFile:
WriteLineInfo(CurLine);
break;
}
}
void PrintPPOutputPPCallbacks::InclusionDirective(SourceLocation HashLoc,
const Token &IncludeTok,
StringRef FileName,
bool IsAngled,
CharSourceRange FilenameRange,
const FileEntry *File,
StringRef SearchPath,
StringRef RelativePath,
const Module *Imported) {
// When preprocessing, turn implicit imports into @imports.
// FIXME: This is a stop-gap until a more comprehensive "preprocessing with
// modules" solution is introduced.
if (Imported) {
startNewLineIfNeeded();
MoveToLine(HashLoc);
OS << "@import " << Imported->getFullModuleName() << ";"
<< " /* clang -E: implicit import for \"" << File->getName() << "\" */";
EmittedTokensOnThisLine = true;
}
}
/// Ident - Handle #ident directives when read by the preprocessor.
///
void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, const std::string &S) {
MoveToLine(Loc);
OS.write("#ident ", strlen("#ident "));
OS.write(&S[0], S.size());
EmittedTokensOnThisLine = true;
}
void PrintPPOutputPPCallbacks::PragmaCaptured(SourceLocation Loc,
StringRef Str) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma captured";
setEmittedDirectiveOnThisLine();
}
/// MacroDefined - This hook is called whenever a macro definition is seen.
void PrintPPOutputPPCallbacks::MacroDefined(const Token &MacroNameTok,
const MacroDirective *MD) {
const MacroInfo *MI = MD->getMacroInfo();
// Only print out macro definitions in -dD mode.
if (!DumpDefines ||
// Ignore __FILE__ etc.
MI->isBuiltinMacro()) return;
MoveToLine(MI->getDefinitionLoc());
PrintMacroDefinition(*MacroNameTok.getIdentifierInfo(), *MI, PP, OS);
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::MacroUndefined(const Token &MacroNameTok,
const MacroDirective *MD) {
// Only print out macro definitions in -dD mode.
if (!DumpDefines) return;
MoveToLine(MacroNameTok.getLocation());
OS << "#undef " << MacroNameTok.getIdentifierInfo()->getName();
setEmittedDirectiveOnThisLine();
}
static void outputPrintable(llvm::raw_ostream& OS,
const std::string &Str) {
for (unsigned i = 0, e = Str.size(); i != e; ++i) {
unsigned char Char = Str[i];
if (isPrintable(Char) && Char != '\\' && Char != '"')
OS << (char)Char;
else // Output anything hard as an octal escape.
OS << '\\'
<< (char)('0'+ ((Char >> 6) & 7))
<< (char)('0'+ ((Char >> 3) & 7))
<< (char)('0'+ ((Char >> 0) & 7));
}
}
void PrintPPOutputPPCallbacks::PragmaComment(SourceLocation Loc,
const IdentifierInfo *Kind,
const std::string &Str) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma comment(" << Kind->getName();
if (!Str.empty()) {
OS << ", \"";
outputPrintable(OS, Str);
OS << '"';
}
OS << ')';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaDetectMismatch(SourceLocation Loc,
const std::string &Name,
const std::string &Value) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma detect_mismatch(\"" << Name << '"';
outputPrintable(OS, Name);
OS << "\", \"";
outputPrintable(OS, Value);
OS << "\")";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaMessage(SourceLocation Loc,
StringRef Namespace,
PragmaMessageKind Kind,
StringRef Str) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma ";
if (!Namespace.empty())
OS << Namespace << ' ';
switch (Kind) {
case PMK_Message:
OS << "message(\"";
break;
case PMK_Warning:
OS << "warning \"";
break;
case PMK_Error:
OS << "error \"";
break;
}
outputPrintable(OS, Str);
OS << '"';
if (Kind == PMK_Message)
OS << ')';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaDebug(SourceLocation Loc,
StringRef DebugType) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma clang __debug ";
OS << DebugType;
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma " << Namespace << " diagnostic push";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma " << Namespace << " diagnostic pop";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaDiagnostic(SourceLocation Loc, StringRef Namespace,
diag::Mapping Map, StringRef Str) {
startNewLineIfNeeded();
MoveToLine(Loc);
OS << "#pragma " << Namespace << " diagnostic ";
switch (Map) {
case diag::MAP_WARNING:
OS << "warning";
break;
case diag::MAP_ERROR:
OS << "error";
break;
case diag::MAP_IGNORE:
OS << "ignored";
break;
case diag::MAP_FATAL:
OS << "fatal";
break;
}
OS << " \"" << Str << '"';
setEmittedDirectiveOnThisLine();
}
/// HandleFirstTokOnLine - When emitting a preprocessed file in -E mode, this
/// is called for the first token on each new line. If this really is the start
/// of a new logical line, handle it and return true, otherwise return false.
/// This may not be the start of a logical line because the "start of line"
/// marker is set for spelling lines, not expansion ones.
bool PrintPPOutputPPCallbacks::HandleFirstTokOnLine(Token &Tok) {
// Figure out what line we went to and insert the appropriate number of
// newline characters.
if (!MoveToLine(Tok.getLocation()))
return false;
// Print out space characters so that the first token on a line is
// indented for easy reading.
unsigned ColNo = SM.getExpansionColumnNumber(Tok.getLocation());
// This hack prevents stuff like:
// #define HASH #
// HASH define foo bar
// From having the # character end up at column 1, which makes it so it
// is not handled as a #define next time through the preprocessor if in
// -fpreprocessed mode.
if (ColNo <= 1 && Tok.is(tok::hash))
OS << ' ';
// Otherwise, indent the appropriate number of spaces.
for (; ColNo > 1; --ColNo)
OS << ' ';
return true;
}
void PrintPPOutputPPCallbacks::HandleNewlinesInToken(const char *TokStr,
unsigned Len) {
unsigned NumNewlines = 0;
for (; Len; --Len, ++TokStr) {
if (*TokStr != '\n' &&
*TokStr != '\r')
continue;
++NumNewlines;
// If we have \n\r or \r\n, skip both and count as one line.
if (Len != 1 &&
(TokStr[1] == '\n' || TokStr[1] == '\r') &&
TokStr[0] != TokStr[1])
++TokStr, --Len;
}
if (NumNewlines == 0) return;
CurLine += NumNewlines;
}
namespace {
struct UnknownPragmaHandler : public PragmaHandler {
const char *Prefix;
PrintPPOutputPPCallbacks *Callbacks;
UnknownPragmaHandler(const char *prefix, PrintPPOutputPPCallbacks *callbacks)
: Prefix(prefix), Callbacks(callbacks) {}
virtual void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
Token &PragmaTok) {
// Figure out what line we went to and insert the appropriate number of
// newline characters.
Callbacks->startNewLineIfNeeded();
Callbacks->MoveToLine(PragmaTok.getLocation());
Callbacks->OS.write(Prefix, strlen(Prefix));
// Read and print all of the pragma tokens.
while (PragmaTok.isNot(tok::eod)) {
if (PragmaTok.hasLeadingSpace())
Callbacks->OS << ' ';
std::string TokSpell = PP.getSpelling(PragmaTok);
Callbacks->OS.write(&TokSpell[0], TokSpell.size());
PP.LexUnexpandedToken(PragmaTok);
}
Callbacks->setEmittedDirectiveOnThisLine();
}
};
} // end anonymous namespace
static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok,
PrintPPOutputPPCallbacks *Callbacks,
raw_ostream &OS) {
bool DropComments = PP.getLangOpts().TraditionalCPP &&
!PP.getCommentRetentionState();
char Buffer[256];
Token PrevPrevTok, PrevTok;
PrevPrevTok.startToken();
PrevTok.startToken();
while (1) {
if (Callbacks->hasEmittedDirectiveOnThisLine()) {
Callbacks->startNewLineIfNeeded();
Callbacks->MoveToLine(Tok.getLocation());
}
// If this token is at the start of a line, emit newlines if needed.
if (Tok.isAtStartOfLine() && Callbacks->HandleFirstTokOnLine(Tok)) {
// done.
} else if (Tok.hasLeadingSpace() ||
// If we haven't emitted a token on this line yet, PrevTok isn't
// useful to look at and no concatenation could happen anyway.
(Callbacks->hasEmittedTokensOnThisLine() &&
// Don't print "-" next to "-", it would form "--".
Callbacks->AvoidConcat(PrevPrevTok, PrevTok, Tok))) {
OS << ' ';
}
if (DropComments && Tok.is(tok::comment)) {
// Skip comments. Normally the preprocessor does not generate
// tok::comment nodes at all when not keeping comments, but under
// -traditional-cpp the lexer keeps /all/ whitespace, including comments.
SourceLocation StartLoc = Tok.getLocation();
Callbacks->MoveToLine(StartLoc.getLocWithOffset(Tok.getLength()));
} else if (IdentifierInfo *II = Tok.getIdentifierInfo()) {
OS << II->getName();
} else if (Tok.isLiteral() && !Tok.needsCleaning() &&
Tok.getLiteralData()) {
OS.write(Tok.getLiteralData(), Tok.getLength());
} else if (Tok.getLength() < 256) {
const char *TokPtr = Buffer;
unsigned Len = PP.getSpelling(Tok, TokPtr);
OS.write(TokPtr, Len);
// Tokens that can contain embedded newlines need to adjust our current
// line number.
if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)
Callbacks->HandleNewlinesInToken(TokPtr, Len);
} else {
std::string S = PP.getSpelling(Tok);
OS.write(&S[0], S.size());
// Tokens that can contain embedded newlines need to adjust our current
// line number.
if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)
Callbacks->HandleNewlinesInToken(&S[0], S.size());
}
Callbacks->setEmittedTokensOnThisLine();
if (Tok.is(tok::eof)) break;
PrevPrevTok = PrevTok;
PrevTok = Tok;
PP.Lex(Tok);
}
}
typedef std::pair<const IdentifierInfo *, MacroInfo *> id_macro_pair;
static int MacroIDCompare(const void* a, const void* b) {
const id_macro_pair *LHS = static_cast<const id_macro_pair*>(a);
const id_macro_pair *RHS = static_cast<const id_macro_pair*>(b);
return LHS->first->getName().compare(RHS->first->getName());
}
static void DoPrintMacros(Preprocessor &PP, raw_ostream *OS) {
// Ignore unknown pragmas.
PP.AddPragmaHandler(new EmptyPragmaHandler());
// -dM mode just scans and ignores all tokens in the files, then dumps out
// the macro table at the end.
PP.EnterMainSourceFile();
Token Tok;
do PP.Lex(Tok);
while (Tok.isNot(tok::eof));
SmallVector<id_macro_pair, 128> MacrosByID;
for (Preprocessor::macro_iterator I = PP.macro_begin(), E = PP.macro_end();
I != E; ++I) {
if (I->first->hasMacroDefinition())
MacrosByID.push_back(id_macro_pair(I->first, I->second->getMacroInfo()));
}
llvm::array_pod_sort(MacrosByID.begin(), MacrosByID.end(), MacroIDCompare);
for (unsigned i = 0, e = MacrosByID.size(); i != e; ++i) {
MacroInfo &MI = *MacrosByID[i].second;
// Ignore computed macros like __LINE__ and friends.
if (MI.isBuiltinMacro()) continue;
PrintMacroDefinition(*MacrosByID[i].first, MI, PP, *OS);
*OS << '\n';
}
}
/// DoPrintPreprocessedInput - This implements -E mode.
///
void clang::DoPrintPreprocessedInput(Preprocessor &PP, raw_ostream *OS,
const PreprocessorOutputOptions &Opts) {
// Show macros with no output is handled specially.
if (!Opts.ShowCPP) {
assert(Opts.ShowMacros && "Not yet implemented!");
DoPrintMacros(PP, OS);
return;
}
// Inform the preprocessor whether we want it to retain comments or not, due
// to -C or -CC.
PP.SetCommentRetentionState(Opts.ShowComments, Opts.ShowMacroComments);
PrintPPOutputPPCallbacks *Callbacks =
new PrintPPOutputPPCallbacks(PP, *OS, !Opts.ShowLineMarkers,
Opts.ShowMacros);
PP.AddPragmaHandler(new UnknownPragmaHandler("#pragma", Callbacks));
PP.AddPragmaHandler("GCC", new UnknownPragmaHandler("#pragma GCC",Callbacks));
PP.AddPragmaHandler("clang",
new UnknownPragmaHandler("#pragma clang", Callbacks));
PP.addPPCallbacks(Callbacks);
// After we have configured the preprocessor, enter the main file.
PP.EnterMainSourceFile();
// Consume all of the tokens that come from the predefines buffer. Those
// should not be emitted into the output and are guaranteed to be at the
// start.
const SourceManager &SourceMgr = PP.getSourceManager();
Token Tok;
do {
PP.Lex(Tok);
if (Tok.is(tok::eof) || !Tok.getLocation().isFileID())
break;
PresumedLoc PLoc = SourceMgr.getPresumedLoc(Tok.getLocation());
if (PLoc.isInvalid())
break;
if (strcmp(PLoc.getFilename(), "<built-in>"))
break;
} while (true);
// Read all the preprocessed tokens, printing them out to the stream.
PrintPreprocessedTokens(PP, Tok, Callbacks, *OS);
*OS << '\n';
}