InitPreprocessor.cpp revision 202379 
1//===--- InitPreprocessor.cpp - PP initialization code. ---------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the clang::InitializePreprocessor function.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Frontend/Utils.h"
15#include "clang/Basic/TargetInfo.h"
16#include "clang/Frontend/FrontendDiagnostic.h"
17#include "clang/Frontend/FrontendOptions.h"
18#include "clang/Frontend/PreprocessorOptions.h"
19#include "clang/Lex/Preprocessor.h"
20#include "clang/Basic/FileManager.h"
21#include "clang/Basic/SourceManager.h"
22#include "llvm/ADT/APFloat.h"
23#include "llvm/Support/MemoryBuffer.h"
24#include "llvm/System/Path.h"
25using namespace clang;
26
27// Append a #define line to Buf for Macro.  Macro should be of the form XXX,
28// in which case we emit "#define XXX 1" or "XXX=Y z W" in which case we emit
29// "#define XXX Y z W".  To get a #define with no value, use "XXX=".
30static void DefineBuiltinMacro(MacroBuilder &Builder, llvm::StringRef Macro,
31                               Diagnostic &Diags) {
32  std::pair<llvm::StringRef, llvm::StringRef> MacroPair = Macro.split('=');
33  llvm::StringRef MacroName = MacroPair.first;
34  llvm::StringRef MacroBody = MacroPair.second;
35  if (MacroName.size() != Macro.size()) {
36    // Per GCC -D semantics, the macro ends at \n if it exists.
37    llvm::StringRef::size_type End = MacroBody.find_first_of("\n\r");
38    if (End != llvm::StringRef::npos)
39      Diags.Report(diag::warn_fe_macro_contains_embedded_newline)
40        << MacroName;
41    Builder.defineMacro(MacroName, MacroBody.substr(0, End));
42  } else {
43    // Push "macroname 1".
44    Builder.defineMacro(Macro);
45  }
46}
47
48std::string clang::NormalizeDashIncludePath(llvm::StringRef File) {
49  // Implicit include paths should be resolved relative to the current
50  // working directory first, and then use the regular header search
51  // mechanism. The proper way to handle this is to have the
52  // predefines buffer located at the current working directory, but
53  // it has not file entry. For now, workaround this by using an
54  // absolute path if we find the file here, and otherwise letting
55  // header search handle it.
56  llvm::sys::Path Path(File);
57  Path.makeAbsolute();
58  if (!Path.exists())
59    Path = File;
60
61  return Lexer::Stringify(Path.str());
62}
63
64/// AddImplicitInclude - Add an implicit #include of the specified file to the
65/// predefines buffer.
66static void AddImplicitInclude(MacroBuilder &Builder, llvm::StringRef File) {
67  Builder.append("#include \"" +
68                 llvm::Twine(NormalizeDashIncludePath(File)) + "\"");
69}
70
71static void AddImplicitIncludeMacros(MacroBuilder &Builder,
72                                     llvm::StringRef File) {
73  Builder.append("#__include_macros \"" +
74                 llvm::Twine(NormalizeDashIncludePath(File)) + "\"");
75  // Marker token to stop the __include_macros fetch loop.
76  Builder.append("##"); // ##?
77}
78
79/// AddImplicitIncludePTH - Add an implicit #include using the original file
80///  used to generate a PTH cache.
81static void AddImplicitIncludePTH(MacroBuilder &Builder, Preprocessor &PP,
82                                  llvm::StringRef ImplicitIncludePTH) {
83  PTHManager *P = PP.getPTHManager();
84  assert(P && "No PTHManager.");
85  const char *OriginalFile = P->getOriginalSourceFile();
86
87  if (!OriginalFile) {
88    PP.getDiagnostics().Report(diag::err_fe_pth_file_has_no_source_header)
89      << ImplicitIncludePTH;
90    return;
91  }
92
93  AddImplicitInclude(Builder, OriginalFile);
94}
95
96/// PickFP - This is used to pick a value based on the FP semantics of the
97/// specified FP model.
98template <typename T>
99static T PickFP(const llvm::fltSemantics *Sem, T IEEESingleVal,
100                T IEEEDoubleVal, T X87DoubleExtendedVal, T PPCDoubleDoubleVal,
101                T IEEEQuadVal) {
102  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEsingle)
103    return IEEESingleVal;
104  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEdouble)
105    return IEEEDoubleVal;
106  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::x87DoubleExtended)
107    return X87DoubleExtendedVal;
108  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::PPCDoubleDouble)
109    return PPCDoubleDoubleVal;
110  assert(Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEquad);
111  return IEEEQuadVal;
112}
113
114static void DefineFloatMacros(MacroBuilder &Builder, llvm::StringRef Prefix,
115                              const llvm::fltSemantics *Sem) {
116  const char *DenormMin, *Epsilon, *Max, *Min;
117  DenormMin = PickFP(Sem, "1.40129846e-45F", "4.9406564584124654e-324",
118                     "3.64519953188247460253e-4951L",
119                     "4.94065645841246544176568792868221e-324L",
120                     "6.47517511943802511092443895822764655e-4966L");
121  int Digits = PickFP(Sem, 6, 15, 18, 31, 33);
122  Epsilon = PickFP(Sem, "1.19209290e-7F", "2.2204460492503131e-16",
123                   "1.08420217248550443401e-19L",
124                   "4.94065645841246544176568792868221e-324L",
125                   "1.92592994438723585305597794258492732e-34L");
126  int MantissaDigits = PickFP(Sem, 24, 53, 64, 106, 113);
127  int Min10Exp = PickFP(Sem, -37, -307, -4931, -291, -4931);
128  int Max10Exp = PickFP(Sem, 38, 308, 4932, 308, 4932);
129  int MinExp = PickFP(Sem, -125, -1021, -16381, -968, -16381);
130  int MaxExp = PickFP(Sem, 128, 1024, 16384, 1024, 16384);
131  Min = PickFP(Sem, "1.17549435e-38F", "2.2250738585072014e-308",
132               "3.36210314311209350626e-4932L",
133               "2.00416836000897277799610805135016e-292L",
134               "3.36210314311209350626267781732175260e-4932L");
135  Max = PickFP(Sem, "3.40282347e+38F", "1.7976931348623157e+308",
136               "1.18973149535723176502e+4932L",
137               "1.79769313486231580793728971405301e+308L",
138               "1.18973149535723176508575932662800702e+4932L");
139
140  llvm::Twine DefPrefix = "__" + Prefix + "_";
141
142  Builder.defineMacro(DefPrefix + "DENORM_MIN__", DenormMin);
143  Builder.defineMacro(DefPrefix + "HAS_DENORM__");
144  Builder.defineMacro(DefPrefix + "DIG__", llvm::Twine(Digits));
145  Builder.defineMacro(DefPrefix + "EPSILON__", llvm::Twine(Epsilon));
146  Builder.defineMacro(DefPrefix + "HAS_INFINITY__");
147  Builder.defineMacro(DefPrefix + "HAS_QUIET_NAN__");
148  Builder.defineMacro(DefPrefix + "MANT_DIG__", llvm::Twine(MantissaDigits));
149
150  Builder.defineMacro(DefPrefix + "MAX_10_EXP__", llvm::Twine(Max10Exp));
151  Builder.defineMacro(DefPrefix + "MAX_EXP__", llvm::Twine(MaxExp));
152  Builder.defineMacro(DefPrefix + "MAX__", llvm::Twine(Max));
153
154  Builder.defineMacro(DefPrefix + "MIN_10_EXP__","("+llvm::Twine(Min10Exp)+")");
155  Builder.defineMacro(DefPrefix + "MIN_EXP__", "("+llvm::Twine(MinExp)+")");
156  Builder.defineMacro(DefPrefix + "MIN__", llvm::Twine(Min));
157}
158
159
160/// DefineTypeSize - Emit a macro to the predefines buffer that declares a macro
161/// named MacroName with the max value for a type with width 'TypeWidth' a
162/// signedness of 'isSigned' and with a value suffix of 'ValSuffix' (e.g. LL).
163static void DefineTypeSize(llvm::StringRef MacroName, unsigned TypeWidth,
164                           llvm::StringRef ValSuffix, bool isSigned,
165                           MacroBuilder& Builder) {
166  long long MaxVal;
167  if (isSigned)
168    MaxVal = (1LL << (TypeWidth - 1)) - 1;
169  else
170    MaxVal = ~0LL >> (64-TypeWidth);
171
172  Builder.defineMacro(MacroName, llvm::Twine(MaxVal) + ValSuffix);
173}
174
175/// DefineTypeSize - An overloaded helper that uses TargetInfo to determine
176/// the width, suffix, and signedness of the given type
177static void DefineTypeSize(llvm::StringRef MacroName, TargetInfo::IntType Ty,
178                           const TargetInfo &TI, MacroBuilder &Builder) {
179  DefineTypeSize(MacroName, TI.getTypeWidth(Ty), TI.getTypeConstantSuffix(Ty),
180                 TI.isTypeSigned(Ty), Builder);
181}
182
183static void DefineType(const llvm::Twine &MacroName, TargetInfo::IntType Ty,
184                       MacroBuilder &Builder) {
185  Builder.defineMacro(MacroName, TargetInfo::getTypeName(Ty));
186}
187
188static void DefineTypeWidth(llvm::StringRef MacroName, TargetInfo::IntType Ty,
189                            const TargetInfo &TI, MacroBuilder &Builder) {
190  Builder.defineMacro(MacroName, llvm::Twine(TI.getTypeWidth(Ty)));
191}
192
193static void DefineExactWidthIntType(TargetInfo::IntType Ty,
194                               const TargetInfo &TI, MacroBuilder &Builder) {
195  int TypeWidth = TI.getTypeWidth(Ty);
196  DefineType("__INT" + llvm::Twine(TypeWidth) + "_TYPE__", Ty, Builder);
197
198  llvm::StringRef ConstSuffix(TargetInfo::getTypeConstantSuffix(Ty));
199  if (!ConstSuffix.empty())
200    Builder.defineMacro("__INT" + llvm::Twine(TypeWidth) + "_C_SUFFIX__",
201                        ConstSuffix);
202}
203
204static void InitializePredefinedMacros(const TargetInfo &TI,
205                                       const LangOptions &LangOpts,
206                                       const FrontendOptions &FEOpts,
207                                       MacroBuilder &Builder) {
208  // Compiler version introspection macros.
209  Builder.defineMacro("__llvm__");  // LLVM Backend
210  Builder.defineMacro("__clang__"); // Clang Frontend
211
212  // Currently claim to be compatible with GCC 4.2.1-5621.
213  Builder.defineMacro("__GNUC_MINOR__", "2");
214  Builder.defineMacro("__GNUC_PATCHLEVEL__", "1");
215  Builder.defineMacro("__GNUC__", "4");
216  Builder.defineMacro("__GXX_ABI_VERSION", "1002");
217  Builder.defineMacro("__VERSION__", "\"4.2.1 Compatible Clang Compiler\"");
218
219  // Initialize language-specific preprocessor defines.
220
221  // These should all be defined in the preprocessor according to the
222  // current language configuration.
223  if (!LangOpts.Microsoft)
224    Builder.defineMacro("__STDC__");
225  if (LangOpts.AsmPreprocessor)
226    Builder.defineMacro("__ASSEMBLER__");
227
228  if (!LangOpts.CPlusPlus) {
229    if (LangOpts.C99)
230      Builder.defineMacro("__STDC_VERSION__", "199901L");
231    else if (!LangOpts.GNUMode && LangOpts.Digraphs)
232      Builder.defineMacro("__STDC_VERSION__", "199409L");
233  }
234
235  // Standard conforming mode?
236  if (!LangOpts.GNUMode)
237    Builder.defineMacro("__STRICT_ANSI__");
238
239  if (LangOpts.CPlusPlus0x)
240    Builder.defineMacro("__GXX_EXPERIMENTAL_CXX0X__");
241
242  if (LangOpts.Freestanding)
243    Builder.defineMacro("__STDC_HOSTED__", "0");
244  else
245    Builder.defineMacro("__STDC_HOSTED__");
246
247  if (LangOpts.ObjC1) {
248    Builder.defineMacro("__OBJC__");
249    if (LangOpts.ObjCNonFragileABI) {
250      Builder.defineMacro("__OBJC2__");
251      Builder.defineMacro("OBJC_ZEROCOST_EXCEPTIONS");
252    }
253
254    if (LangOpts.getGCMode() != LangOptions::NonGC)
255      Builder.defineMacro("__OBJC_GC__");
256
257    if (LangOpts.NeXTRuntime)
258      Builder.defineMacro("__NEXT_RUNTIME__");
259  }
260
261  // darwin_constant_cfstrings controls this. This is also dependent
262  // on other things like the runtime I believe.  This is set even for C code.
263  Builder.defineMacro("__CONSTANT_CFSTRINGS__");
264
265  if (LangOpts.ObjC2)
266    Builder.defineMacro("OBJC_NEW_PROPERTIES");
267
268  if (LangOpts.PascalStrings)
269    Builder.defineMacro("__PASCAL_STRINGS__");
270
271  if (LangOpts.Blocks) {
272    Builder.defineMacro("__block", "__attribute__((__blocks__(byref)))");
273    Builder.defineMacro("__BLOCKS__");
274  }
275
276  if (LangOpts.Exceptions)
277    Builder.defineMacro("__EXCEPTIONS");
278
279  if (LangOpts.CPlusPlus) {
280    Builder.defineMacro("__DEPRECATED");
281    Builder.defineMacro("__GNUG__", "4");
282    Builder.defineMacro("__GXX_WEAK__");
283    if (LangOpts.GNUMode)
284      Builder.defineMacro("__cplusplus");
285    else
286      // C++ [cpp.predefined]p1:
287      //   The name_ _cplusplusis defined to the value199711Lwhen compiling a
288      //   C++ translation unit.
289      Builder.defineMacro("__cplusplus", "199711L");
290    Builder.defineMacro("__private_extern__", "extern");
291    // Ugly hack to work with GNU libstdc++.
292    Builder.defineMacro("_GNU_SOURCE");
293  }
294
295  if (LangOpts.Microsoft) {
296    // Filter out some microsoft extensions when trying to parse in ms-compat
297    // mode.
298    Builder.defineMacro("__int8", "__INT8_TYPE__");
299    Builder.defineMacro("__int16", "__INT16_TYPE__");
300    Builder.defineMacro("__int32", "__INT32_TYPE__");
301    Builder.defineMacro("__int64", "__INT64_TYPE__");
302    // Both __PRETTY_FUNCTION__ and __FUNCTION__ are GCC extensions, however
303    // VC++ appears to only like __FUNCTION__.
304    Builder.defineMacro("__PRETTY_FUNCTION__", "__FUNCTION__");
305    // Work around some issues with Visual C++ headerws.
306    if (LangOpts.CPlusPlus) {
307      // Since we define wchar_t in C++ mode.
308      Builder.defineMacro("_WCHAR_T_DEFINED");
309      Builder.defineMacro("_NATIVE_WCHAR_T_DEFINED");
310      // FIXME:  This should be temporary until we have a __pragma
311      // solution, to avoid some errors flagged in VC++ headers.
312      Builder.defineMacro("_CRT_SECURE_CPP_OVERLOAD_SECURE_NAMES", "0");
313    }
314  }
315
316  if (LangOpts.Optimize)
317    Builder.defineMacro("__OPTIMIZE__");
318  if (LangOpts.OptimizeSize)
319    Builder.defineMacro("__OPTIMIZE_SIZE__");
320
321  // Initialize target-specific preprocessor defines.
322
323  // Define type sizing macros based on the target properties.
324  assert(TI.getCharWidth() == 8 && "Only support 8-bit char so far");
325  Builder.defineMacro("__CHAR_BIT__", "8");
326
327  DefineTypeSize("__SCHAR_MAX__", TI.getCharWidth(), "", true, Builder);
328  DefineTypeSize("__SHRT_MAX__", TargetInfo::SignedShort, TI, Builder);
329  DefineTypeSize("__INT_MAX__", TargetInfo::SignedInt, TI, Builder);
330  DefineTypeSize("__LONG_MAX__", TargetInfo::SignedLong, TI, Builder);
331  DefineTypeSize("__LONG_LONG_MAX__", TargetInfo::SignedLongLong, TI, Builder);
332  DefineTypeSize("__WCHAR_MAX__", TI.getWCharType(), TI, Builder);
333  DefineTypeSize("__INTMAX_MAX__", TI.getIntMaxType(), TI, Builder);
334
335  DefineType("__INTMAX_TYPE__", TI.getIntMaxType(), Builder);
336  DefineType("__UINTMAX_TYPE__", TI.getUIntMaxType(), Builder);
337  DefineTypeWidth("__INTMAX_WIDTH__",  TI.getIntMaxType(), TI, Builder);
338  DefineType("__PTRDIFF_TYPE__", TI.getPtrDiffType(0), Builder);
339  DefineTypeWidth("__PTRDIFF_WIDTH__", TI.getPtrDiffType(0), TI, Builder);
340  DefineType("__INTPTR_TYPE__", TI.getIntPtrType(), Builder);
341  DefineTypeWidth("__INTPTR_WIDTH__", TI.getIntPtrType(), TI, Builder);
342  DefineType("__SIZE_TYPE__", TI.getSizeType(), Builder);
343  DefineTypeWidth("__SIZE_WIDTH__", TI.getSizeType(), TI, Builder);
344  DefineType("__WCHAR_TYPE__", TI.getWCharType(), Builder);
345  DefineTypeWidth("__WCHAR_WIDTH__", TI.getWCharType(), TI, Builder);
346  DefineType("__WINT_TYPE__", TI.getWIntType(), Builder);
347  DefineTypeWidth("__WINT_WIDTH__", TI.getWIntType(), TI, Builder);
348  DefineTypeWidth("__SIG_ATOMIC_WIDTH__", TI.getSigAtomicType(), TI, Builder);
349
350  DefineFloatMacros(Builder, "FLT", &TI.getFloatFormat());
351  DefineFloatMacros(Builder, "DBL", &TI.getDoubleFormat());
352  DefineFloatMacros(Builder, "LDBL", &TI.getLongDoubleFormat());
353
354  // Define a __POINTER_WIDTH__ macro for stdint.h.
355  Builder.defineMacro("__POINTER_WIDTH__",
356                      llvm::Twine((int)TI.getPointerWidth(0)));
357
358  if (!LangOpts.CharIsSigned)
359    Builder.defineMacro("__CHAR_UNSIGNED__");
360
361  // Define exact-width integer types for stdint.h
362  Builder.defineMacro("__INT" + llvm::Twine(TI.getCharWidth()) + "_TYPE__",
363                      "char");
364
365  if (TI.getShortWidth() > TI.getCharWidth())
366    DefineExactWidthIntType(TargetInfo::SignedShort, TI, Builder);
367
368  if (TI.getIntWidth() > TI.getShortWidth())
369    DefineExactWidthIntType(TargetInfo::SignedInt, TI, Builder);
370
371  if (TI.getLongWidth() > TI.getIntWidth())
372    DefineExactWidthIntType(TargetInfo::SignedLong, TI, Builder);
373
374  if (TI.getLongLongWidth() > TI.getLongWidth())
375    DefineExactWidthIntType(TargetInfo::SignedLongLong, TI, Builder);
376
377  // Add __builtin_va_list typedef.
378  Builder.append(TI.getVAListDeclaration());
379
380  if (const char *Prefix = TI.getUserLabelPrefix())
381    Builder.defineMacro("__USER_LABEL_PREFIX__", Prefix);
382
383  // Build configuration options.  FIXME: these should be controlled by
384  // command line options or something.
385  Builder.defineMacro("__FINITE_MATH_ONLY__", "0");
386
387  if (LangOpts.GNUInline)
388    Builder.defineMacro("__GNUC_GNU_INLINE__");
389  else
390    Builder.defineMacro("__GNUC_STDC_INLINE__");
391
392  if (LangOpts.NoInline)
393    Builder.defineMacro("__NO_INLINE__");
394
395  if (unsigned PICLevel = LangOpts.PICLevel) {
396    Builder.defineMacro("__PIC__", llvm::Twine(PICLevel));
397    Builder.defineMacro("__pic__", llvm::Twine(PICLevel));
398  }
399
400  // Macros to control C99 numerics and <float.h>
401  Builder.defineMacro("__FLT_EVAL_METHOD__", "0");
402  Builder.defineMacro("__FLT_RADIX__", "2");
403  int Dig = PickFP(&TI.getLongDoubleFormat(), -1/*FIXME*/, 17, 21, 33, 36);
404  Builder.defineMacro("__DECIMAL_DIG__", llvm::Twine(Dig));
405
406  if (LangOpts.getStackProtectorMode() == LangOptions::SSPOn)
407    Builder.defineMacro("__SSP__");
408  else if (LangOpts.getStackProtectorMode() == LangOptions::SSPReq)
409    Builder.defineMacro("__SSP_ALL__", "2");
410
411  if (FEOpts.ProgramAction == frontend::RewriteObjC)
412    Builder.defineMacro("__weak", "__attribute__((objc_gc(weak)))");
413  // Get other target #defines.
414  TI.getTargetDefines(LangOpts, Builder);
415}
416
417// Initialize the remapping of files to alternative contents, e.g.,
418// those specified through other files.
419static void InitializeFileRemapping(Diagnostic &Diags,
420                                    SourceManager &SourceMgr,
421                                    FileManager &FileMgr,
422                                    const PreprocessorOptions &InitOpts) {
423  // Remap files in the source manager.
424  for (PreprocessorOptions::remapped_file_iterator
425         Remap = InitOpts.remapped_file_begin(),
426         RemapEnd = InitOpts.remapped_file_end();
427       Remap != RemapEnd;
428       ++Remap) {
429    // Find the file that we're mapping to.
430    const FileEntry *ToFile = FileMgr.getFile(Remap->second);
431    if (!ToFile) {
432      Diags.Report(diag::err_fe_remap_missing_to_file)
433        << Remap->first << Remap->second;
434      continue;
435    }
436
437    // Create the file entry for the file that we're mapping from.
438    const FileEntry *FromFile = FileMgr.getVirtualFile(Remap->first,
439                                                       ToFile->getSize(),
440                                                       0);
441    if (!FromFile) {
442      Diags.Report(diag::err_fe_remap_missing_from_file)
443        << Remap->first;
444      continue;
445    }
446
447    // Load the contents of the file we're mapping to.
448    std::string ErrorStr;
449    const llvm::MemoryBuffer *Buffer
450      = llvm::MemoryBuffer::getFile(ToFile->getName(), &ErrorStr);
451    if (!Buffer) {
452      Diags.Report(diag::err_fe_error_opening)
453        << Remap->second << ErrorStr;
454      continue;
455    }
456
457    // Override the contents of the "from" file with the contents of
458    // the "to" file.
459    SourceMgr.overrideFileContents(FromFile, Buffer);
460  }
461}
462
463/// InitializePreprocessor - Initialize the preprocessor getting it and the
464/// environment ready to process a single file. This returns true on error.
465///
466void clang::InitializePreprocessor(Preprocessor &PP,
467                                   const PreprocessorOptions &InitOpts,
468                                   const HeaderSearchOptions &HSOpts,
469                                   const FrontendOptions &FEOpts) {
470  std::string PredefineBuffer;
471  PredefineBuffer.reserve(4080);
472  llvm::raw_string_ostream Predefines(PredefineBuffer);
473  MacroBuilder Builder(Predefines);
474
475  InitializeFileRemapping(PP.getDiagnostics(), PP.getSourceManager(),
476                          PP.getFileManager(), InitOpts);
477
478  Builder.append("# 1 \"<built-in>\" 3");
479
480  // Install things like __POWERPC__, __GNUC__, etc into the macro table.
481  if (InitOpts.UsePredefines)
482    InitializePredefinedMacros(PP.getTargetInfo(), PP.getLangOptions(),
483                               FEOpts, Builder);
484
485  // Add on the predefines from the driver.  Wrap in a #line directive to report
486  // that they come from the command line.
487  Builder.append("# 1 \"<command line>\" 1");
488
489  // Process #define's and #undef's in the order they are given.
490  for (unsigned i = 0, e = InitOpts.Macros.size(); i != e; ++i) {
491    if (InitOpts.Macros[i].second)  // isUndef
492      Builder.undefineMacro(InitOpts.Macros[i].first);
493    else
494      DefineBuiltinMacro(Builder, InitOpts.Macros[i].first,
495                         PP.getDiagnostics());
496  }
497
498  // If -imacros are specified, include them now.  These are processed before
499  // any -include directives.
500  for (unsigned i = 0, e = InitOpts.MacroIncludes.size(); i != e; ++i)
501    AddImplicitIncludeMacros(Builder, InitOpts.MacroIncludes[i]);
502
503  // Process -include directives.
504  for (unsigned i = 0, e = InitOpts.Includes.size(); i != e; ++i) {
505    const std::string &Path = InitOpts.Includes[i];
506    if (Path == InitOpts.ImplicitPTHInclude)
507      AddImplicitIncludePTH(Builder, PP, Path);
508    else
509      AddImplicitInclude(Builder, Path);
510  }
511
512  // Exit the command line and go back to <built-in> (2 is LC_LEAVE).
513  Builder.append("# 1 \"<built-in>\" 2");
514
515  // Copy PredefinedBuffer into the Preprocessor.
516  PP.setPredefines(Predefines.str());
517
518  // Initialize the header search object.
519  ApplyHeaderSearchOptions(PP.getHeaderSearchInfo(), HSOpts,
520                           PP.getLangOptions(),
521                           PP.getTargetInfo().getTriple());
522}
523