InitPreprocessor.cpp revision 1ee4b9e6d2d0d031708e2e6dd52aa9e32b83f1c3 
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/PreprocessorOptions.h"
18#include "clang/Lex/Preprocessor.h"
19#include "clang/Basic/FileManager.h"
20#include "clang/Basic/SourceManager.h"
21#include "llvm/ADT/APFloat.h"
22#include "llvm/Support/MemoryBuffer.h"
23#include "llvm/System/Path.h"
24using namespace clang;
25
26// Append a #define line to Buf for Macro.  Macro should be of the form XXX,
27// in which case we emit "#define XXX 1" or "XXX=Y z W" in which case we emit
28// "#define XXX Y z W".  To get a #define with no value, use "XXX=".
29static void DefineBuiltinMacro(MacroBuilder &Builder, llvm::StringRef Macro,
30                               Diagnostic &Diags) {
31  std::pair<llvm::StringRef, llvm::StringRef> MacroPair = Macro.split('=');
32  llvm::StringRef MacroName = MacroPair.first;
33  llvm::StringRef MacroBody = MacroPair.second;
34  if (MacroName.size() != Macro.size()) {
35    // Per GCC -D semantics, the macro ends at \n if it exists.
36    llvm::StringRef::size_type End = MacroBody.find_first_of("\n\r");
37    if (End != llvm::StringRef::npos)
38      Diags.Report(diag::warn_fe_macro_contains_embedded_newline)
39        << MacroName;
40    Builder.defineMacro(MacroName, MacroBody.substr(0, End));
41  } else {
42    // Push "macroname 1".
43    Builder.defineMacro(Macro);
44  }
45}
46
47std::string clang::NormalizeDashIncludePath(llvm::StringRef File) {
48  // Implicit include paths should be resolved relative to the current
49  // working directory first, and then use the regular header search
50  // mechanism. The proper way to handle this is to have the
51  // predefines buffer located at the current working directory, but
52  // it has not file entry. For now, workaround this by using an
53  // absolute path if we find the file here, and otherwise letting
54  // header search handle it.
55  llvm::sys::Path Path(File);
56  Path.makeAbsolute();
57  if (!Path.exists())
58    Path = File;
59
60  return Lexer::Stringify(Path.str());
61}
62
63/// AddImplicitInclude - Add an implicit #include of the specified file to the
64/// predefines buffer.
65static void AddImplicitInclude(MacroBuilder &Builder, llvm::StringRef File) {
66  Builder.append("#include \"" +
67                 llvm::Twine(NormalizeDashIncludePath(File)) + "\"");
68}
69
70static void AddImplicitIncludeMacros(MacroBuilder &Builder,
71                                     llvm::StringRef File) {
72  Builder.append("#__include_macros \"" +
73                 llvm::Twine(NormalizeDashIncludePath(File)) + "\"");
74  // Marker token to stop the __include_macros fetch loop.
75  Builder.append("##"); // ##?
76}
77
78/// AddImplicitIncludePTH - Add an implicit #include using the original file
79///  used to generate a PTH cache.
80static void AddImplicitIncludePTH(MacroBuilder &Builder, Preprocessor &PP,
81                                  llvm::StringRef ImplicitIncludePTH) {
82  PTHManager *P = PP.getPTHManager();
83  assert(P && "No PTHManager.");
84  const char *OriginalFile = P->getOriginalSourceFile();
85
86  if (!OriginalFile) {
87    PP.getDiagnostics().Report(diag::err_fe_pth_file_has_no_source_header)
88      << ImplicitIncludePTH;
89    return;
90  }
91
92  AddImplicitInclude(Builder, OriginalFile);
93}
94
95/// PickFP - This is used to pick a value based on the FP semantics of the
96/// specified FP model.
97template <typename T>
98static T PickFP(const llvm::fltSemantics *Sem, T IEEESingleVal,
99                T IEEEDoubleVal, T X87DoubleExtendedVal, T PPCDoubleDoubleVal,
100                T IEEEQuadVal) {
101  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEsingle)
102    return IEEESingleVal;
103  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEdouble)
104    return IEEEDoubleVal;
105  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::x87DoubleExtended)
106    return X87DoubleExtendedVal;
107  if (Sem == (const llvm::fltSemantics*)&llvm::APFloat::PPCDoubleDouble)
108    return PPCDoubleDoubleVal;
109  assert(Sem == (const llvm::fltSemantics*)&llvm::APFloat::IEEEquad);
110  return IEEEQuadVal;
111}
112
113static void DefineFloatMacros(MacroBuilder &Builder, llvm::StringRef Prefix,
114                              const llvm::fltSemantics *Sem) {
115  const char *DenormMin, *Epsilon, *Max, *Min;
116  DenormMin = PickFP(Sem, "1.40129846e-45F", "4.9406564584124654e-324",
117                     "3.64519953188247460253e-4951L",
118                     "4.94065645841246544176568792868221e-324L",
119                     "6.47517511943802511092443895822764655e-4966L");
120  int Digits = PickFP(Sem, 6, 15, 18, 31, 33);
121  Epsilon = PickFP(Sem, "1.19209290e-7F", "2.2204460492503131e-16",
122                   "1.08420217248550443401e-19L",
123                   "4.94065645841246544176568792868221e-324L",
124                   "1.92592994438723585305597794258492732e-34L");
125  int MantissaDigits = PickFP(Sem, 24, 53, 64, 106, 113);
126  int Min10Exp = PickFP(Sem, -37, -307, -4931, -291, -4931);
127  int Max10Exp = PickFP(Sem, 38, 308, 4932, 308, 4932);
128  int MinExp = PickFP(Sem, -125, -1021, -16381, -968, -16381);
129  int MaxExp = PickFP(Sem, 128, 1024, 16384, 1024, 16384);
130  Min = PickFP(Sem, "1.17549435e-38F", "2.2250738585072014e-308",
131               "3.36210314311209350626e-4932L",
132               "2.00416836000897277799610805135016e-292L",
133               "3.36210314311209350626267781732175260e-4932L");
134  Max = PickFP(Sem, "3.40282347e+38F", "1.7976931348623157e+308",
135               "1.18973149535723176502e+4932L",
136               "1.79769313486231580793728971405301e+308L",
137               "1.18973149535723176508575932662800702e+4932L");
138
139  llvm::Twine DefPrefix = "__" + Prefix + "_";
140
141  Builder.defineMacro(DefPrefix + "DENORM_MIN__", DenormMin);
142  Builder.defineMacro(DefPrefix + "HAS_DENORM__");
143  Builder.defineMacro(DefPrefix + "DIG__", llvm::Twine(Digits));
144  Builder.defineMacro(DefPrefix + "EPSILON__", llvm::Twine(Epsilon));
145  Builder.defineMacro(DefPrefix + "HAS_INFINITY__");
146  Builder.defineMacro(DefPrefix + "HAS_QUIET_NAN__");
147  Builder.defineMacro(DefPrefix + "MANT_DIG__", llvm::Twine(MantissaDigits));
148
149  Builder.defineMacro(DefPrefix + "MAX_10_EXP__", llvm::Twine(Max10Exp));
150  Builder.defineMacro(DefPrefix + "MAX_EXP__", llvm::Twine(MaxExp));
151  Builder.defineMacro(DefPrefix + "MAX__", llvm::Twine(Max));
152
153  Builder.defineMacro(DefPrefix + "MIN_10_EXP__","("+llvm::Twine(Min10Exp)+")");
154  Builder.defineMacro(DefPrefix + "MIN_EXP__", "("+llvm::Twine(MinExp)+")");
155  Builder.defineMacro(DefPrefix + "MIN__", llvm::Twine(Min));
156}
157
158
159/// DefineTypeSize - Emit a macro to the predefines buffer that declares a macro
160/// named MacroName with the max value for a type with width 'TypeWidth' a
161/// signedness of 'isSigned' and with a value suffix of 'ValSuffix' (e.g. LL).
162static void DefineTypeSize(llvm::StringRef MacroName, unsigned TypeWidth,
163                           llvm::StringRef ValSuffix, bool isSigned,
164                           MacroBuilder& Builder) {
165  long long MaxVal;
166  if (isSigned)
167    MaxVal = (1LL << (TypeWidth - 1)) - 1;
168  else
169    MaxVal = ~0LL >> (64-TypeWidth);
170
171  Builder.defineMacro(MacroName, llvm::Twine(MaxVal) + ValSuffix);
172}
173
174/// DefineTypeSize - An overloaded helper that uses TargetInfo to determine
175/// the width, suffix, and signedness of the given type
176static void DefineTypeSize(llvm::StringRef MacroName, TargetInfo::IntType Ty,
177                           const TargetInfo &TI, MacroBuilder &Builder) {
178  DefineTypeSize(MacroName, TI.getTypeWidth(Ty), TI.getTypeConstantSuffix(Ty),
179                 TI.isTypeSigned(Ty), Builder);
180}
181
182static void DefineType(const llvm::Twine &MacroName, TargetInfo::IntType Ty,
183                       MacroBuilder &Builder) {
184  Builder.defineMacro(MacroName, TargetInfo::getTypeName(Ty));
185}
186
187static void DefineTypeWidth(llvm::StringRef MacroName, TargetInfo::IntType Ty,
188                            const TargetInfo &TI, MacroBuilder &Builder) {
189  Builder.defineMacro(MacroName, llvm::Twine(TI.getTypeWidth(Ty)));
190}
191
192static void DefineExactWidthIntType(TargetInfo::IntType Ty,
193                               const TargetInfo &TI, MacroBuilder &Builder) {
194  int TypeWidth = TI.getTypeWidth(Ty);
195  DefineType("__INT" + llvm::Twine(TypeWidth) + "_TYPE__", Ty, Builder);
196
197  llvm::StringRef ConstSuffix(TargetInfo::getTypeConstantSuffix(Ty));
198  if (!ConstSuffix.empty())
199    Builder.defineMacro("__INT" + llvm::Twine(TypeWidth) + "_C_SUFFIX__",
200                        ConstSuffix);
201}
202
203static void InitializePredefinedMacros(const TargetInfo &TI,
204                                       const LangOptions &LangOpts,
205                                       MacroBuilder &Builder) {
206  // Compiler version introspection macros.
207  Builder.defineMacro("__llvm__");  // LLVM Backend
208  Builder.defineMacro("__clang__"); // Clang Frontend
209
210  // Currently claim to be compatible with GCC 4.2.1-5621.
211  Builder.defineMacro("__GNUC_MINOR__", "2");
212  Builder.defineMacro("__GNUC_PATCHLEVEL__", "1");
213  Builder.defineMacro("__GNUC__", "4");
214  Builder.defineMacro("__GXX_ABI_VERSION", "1002");
215  Builder.defineMacro("__VERSION__", "\"4.2.1 Compatible Clang Compiler\"");
216
217  // Initialize language-specific preprocessor defines.
218
219  // These should all be defined in the preprocessor according to the
220  // current language configuration.
221  if (!LangOpts.Microsoft)
222    Builder.defineMacro("__STDC__");
223  if (LangOpts.AsmPreprocessor)
224    Builder.defineMacro("__ASSEMBLER__");
225
226  if (!LangOpts.CPlusPlus) {
227    if (LangOpts.C99)
228      Builder.defineMacro("__STDC_VERSION__", "199901L");
229    else if (!LangOpts.GNUMode && LangOpts.Digraphs)
230      Builder.defineMacro("__STDC_VERSION__", "199409L");
231  }
232
233  // Standard conforming mode?
234  if (!LangOpts.GNUMode)
235    Builder.defineMacro("__STRICT_ANSI__");
236
237  if (LangOpts.CPlusPlus0x)
238    Builder.defineMacro("__GXX_EXPERIMENTAL_CXX0X__");
239
240  if (LangOpts.Freestanding)
241    Builder.defineMacro("__STDC_HOSTED__", "0");
242  else
243    Builder.defineMacro("__STDC_HOSTED__");
244
245  if (LangOpts.ObjC1) {
246    Builder.defineMacro("__OBJC__");
247    if (LangOpts.ObjCNonFragileABI) {
248      Builder.defineMacro("__OBJC2__");
249      Builder.defineMacro("OBJC_ZEROCOST_EXCEPTIONS");
250    }
251
252    if (LangOpts.getGCMode() != LangOptions::NonGC)
253      Builder.defineMacro("__OBJC_GC__");
254
255    if (LangOpts.NeXTRuntime)
256      Builder.defineMacro("__NEXT_RUNTIME__");
257  }
258
259  // darwin_constant_cfstrings controls this. This is also dependent
260  // on other things like the runtime I believe.  This is set even for C code.
261  Builder.defineMacro("__CONSTANT_CFSTRINGS__");
262
263  if (LangOpts.ObjC2)
264    Builder.defineMacro("OBJC_NEW_PROPERTIES");
265
266  if (LangOpts.PascalStrings)
267    Builder.defineMacro("__PASCAL_STRINGS__");
268
269  if (LangOpts.Blocks) {
270    Builder.defineMacro("__block", "__attribute__((__blocks__(byref)))");
271    Builder.defineMacro("__BLOCKS__");
272  }
273
274  if (LangOpts.Exceptions)
275    Builder.defineMacro("__EXCEPTIONS");
276
277  if (LangOpts.CPlusPlus) {
278    Builder.defineMacro("__DEPRECATED");
279    Builder.defineMacro("__GNUG__", "4");
280    Builder.defineMacro("__GXX_WEAK__");
281    if (LangOpts.GNUMode)
282      Builder.defineMacro("__cplusplus");
283    else
284      // C++ [cpp.predefined]p1:
285      //   The name_ _cplusplusis defined to the value199711Lwhen compiling a
286      //   C++ translation unit.
287      Builder.defineMacro("__cplusplus", "199711L");
288    Builder.defineMacro("__private_extern__", "extern");
289    // Ugly hack to work with GNU libstdc++.
290    Builder.defineMacro("_GNU_SOURCE");
291  }
292
293  if (LangOpts.Microsoft) {
294    // Filter out some microsoft extensions when trying to parse in ms-compat
295    // mode.
296    Builder.defineMacro("__int8", "__INT8_TYPE__");
297    Builder.defineMacro("__int16", "__INT16_TYPE__");
298    Builder.defineMacro("__int32", "__INT32_TYPE__");
299    Builder.defineMacro("__int64", "__INT64_TYPE__");
300    // Both __PRETTY_FUNCTION__ and __FUNCTION__ are GCC extensions, however
301    // VC++ appears to only like __FUNCTION__.
302    Builder.defineMacro("__PRETTY_FUNCTION__", "__FUNCTION__");
303    // Work around some issues with Visual C++ headerws.
304    if (LangOpts.CPlusPlus) {
305      // Since we define wchar_t in C++ mode.
306      Builder.defineMacro("_WCHAR_T_DEFINED");
307      Builder.defineMacro("_NATIVE_WCHAR_T_DEFINED");
308      // FIXME:  This should be temporary until we have a __pragma
309      // solution, to avoid some errors flagged in VC++ headers.
310      Builder.defineMacro("_CRT_SECURE_CPP_OVERLOAD_SECURE_NAMES", "0");
311    }
312  }
313
314  if (LangOpts.Optimize)
315    Builder.defineMacro("__OPTIMIZE__");
316  if (LangOpts.OptimizeSize)
317    Builder.defineMacro("__OPTIMIZE_SIZE__");
318
319  // Initialize target-specific preprocessor defines.
320
321  // Define type sizing macros based on the target properties.
322  assert(TI.getCharWidth() == 8 && "Only support 8-bit char so far");
323  Builder.defineMacro("__CHAR_BIT__", "8");
324
325  DefineTypeSize("__SCHAR_MAX__", TI.getCharWidth(), "", true, Builder);
326  DefineTypeSize("__SHRT_MAX__", TargetInfo::SignedShort, TI, Builder);
327  DefineTypeSize("__INT_MAX__", TargetInfo::SignedInt, TI, Builder);
328  DefineTypeSize("__LONG_MAX__", TargetInfo::SignedLong, TI, Builder);
329  DefineTypeSize("__LONG_LONG_MAX__", TargetInfo::SignedLongLong, TI, Builder);
330  DefineTypeSize("__WCHAR_MAX__", TI.getWCharType(), TI, Builder);
331  DefineTypeSize("__INTMAX_MAX__", TI.getIntMaxType(), TI, Builder);
332
333  DefineType("__INTMAX_TYPE__", TI.getIntMaxType(), Builder);
334  DefineType("__UINTMAX_TYPE__", TI.getUIntMaxType(), Builder);
335  DefineTypeWidth("__INTMAX_WIDTH__",  TI.getIntMaxType(), TI, Builder);
336  DefineType("__PTRDIFF_TYPE__", TI.getPtrDiffType(0), Builder);
337  DefineTypeWidth("__PTRDIFF_WIDTH__", TI.getPtrDiffType(0), TI, Builder);
338  DefineType("__INTPTR_TYPE__", TI.getIntPtrType(), Builder);
339  DefineTypeWidth("__INTPTR_WIDTH__", TI.getIntPtrType(), TI, Builder);
340  DefineType("__SIZE_TYPE__", TI.getSizeType(), Builder);
341  DefineTypeWidth("__SIZE_WIDTH__", TI.getSizeType(), TI, Builder);
342  DefineType("__WCHAR_TYPE__", TI.getWCharType(), Builder);
343  DefineTypeWidth("__WCHAR_WIDTH__", TI.getWCharType(), TI, Builder);
344  DefineType("__WINT_TYPE__", TI.getWIntType(), Builder);
345  DefineTypeWidth("__WINT_WIDTH__", TI.getWIntType(), TI, Builder);
346  DefineTypeWidth("__SIG_ATOMIC_WIDTH__", TI.getSigAtomicType(), TI, Builder);
347
348  DefineFloatMacros(Builder, "FLT", &TI.getFloatFormat());
349  DefineFloatMacros(Builder, "DBL", &TI.getDoubleFormat());
350  DefineFloatMacros(Builder, "LDBL", &TI.getLongDoubleFormat());
351
352  // Define a __POINTER_WIDTH__ macro for stdint.h.
353  Builder.defineMacro("__POINTER_WIDTH__",
354                      llvm::Twine((int)TI.getPointerWidth(0)));
355
356  if (!LangOpts.CharIsSigned)
357    Builder.defineMacro("__CHAR_UNSIGNED__");
358
359  // Define exact-width integer types for stdint.h
360  Builder.defineMacro("__INT" + llvm::Twine(TI.getCharWidth()) + "_TYPE__",
361                      "char");
362
363  if (TI.getShortWidth() > TI.getCharWidth())
364    DefineExactWidthIntType(TargetInfo::SignedShort, TI, Builder);
365
366  if (TI.getIntWidth() > TI.getShortWidth())
367    DefineExactWidthIntType(TargetInfo::SignedInt, TI, Builder);
368
369  if (TI.getLongWidth() > TI.getIntWidth())
370    DefineExactWidthIntType(TargetInfo::SignedLong, TI, Builder);
371
372  if (TI.getLongLongWidth() > TI.getLongWidth())
373    DefineExactWidthIntType(TargetInfo::SignedLongLong, TI, Builder);
374
375  // Add __builtin_va_list typedef.
376  Builder.append(TI.getVAListDeclaration());
377
378  if (const char *Prefix = TI.getUserLabelPrefix())
379    Builder.defineMacro("__USER_LABEL_PREFIX__", Prefix);
380
381  // Build configuration options.  FIXME: these should be controlled by
382  // command line options or something.
383  Builder.defineMacro("__FINITE_MATH_ONLY__", "0");
384
385  if (LangOpts.GNUInline)
386    Builder.defineMacro("__GNUC_GNU_INLINE__");
387  else
388    Builder.defineMacro("__GNUC_STDC_INLINE__");
389
390  if (LangOpts.NoInline)
391    Builder.defineMacro("__NO_INLINE__");
392
393  if (unsigned PICLevel = LangOpts.PICLevel) {
394    Builder.defineMacro("__PIC__", llvm::Twine(PICLevel));
395    Builder.defineMacro("__pic__", llvm::Twine(PICLevel));
396  }
397
398  // Macros to control C99 numerics and <float.h>
399  Builder.defineMacro("__FLT_EVAL_METHOD__", "0");
400  Builder.defineMacro("__FLT_RADIX__", "2");
401  int Dig = PickFP(&TI.getLongDoubleFormat(), -1/*FIXME*/, 17, 21, 33, 36);
402  Builder.defineMacro("__DECIMAL_DIG__", llvm::Twine(Dig));
403
404  if (LangOpts.getStackProtectorMode() == LangOptions::SSPOn)
405    Builder.defineMacro("__SSP__");
406  else if (LangOpts.getStackProtectorMode() == LangOptions::SSPReq)
407    Builder.defineMacro("__SSP_ALL__", "2");
408
409  // Get other target #defines.
410  TI.getTargetDefines(LangOpts, Builder);
411}
412
413// Initialize the remapping of files to alternative contents, e.g.,
414// those specified through other files.
415static void InitializeFileRemapping(Diagnostic &Diags,
416                                    SourceManager &SourceMgr,
417                                    FileManager &FileMgr,
418                                    const PreprocessorOptions &InitOpts) {
419  // Remap files in the source manager.
420  for (PreprocessorOptions::remapped_file_iterator
421         Remap = InitOpts.remapped_file_begin(),
422         RemapEnd = InitOpts.remapped_file_end();
423       Remap != RemapEnd;
424       ++Remap) {
425    // Find the file that we're mapping to.
426    const FileEntry *ToFile = FileMgr.getFile(Remap->second);
427    if (!ToFile) {
428      Diags.Report(diag::err_fe_remap_missing_to_file)
429        << Remap->first << Remap->second;
430      continue;
431    }
432
433    // Create the file entry for the file that we're mapping from.
434    const FileEntry *FromFile = FileMgr.getVirtualFile(Remap->first,
435                                                       ToFile->getSize(),
436                                                       0);
437    if (!FromFile) {
438      Diags.Report(diag::err_fe_remap_missing_from_file)
439        << Remap->first;
440      continue;
441    }
442
443    // Load the contents of the file we're mapping to.
444    std::string ErrorStr;
445    const llvm::MemoryBuffer *Buffer
446      = llvm::MemoryBuffer::getFile(ToFile->getName(), &ErrorStr);
447    if (!Buffer) {
448      Diags.Report(diag::err_fe_error_opening)
449        << Remap->second << ErrorStr;
450      continue;
451    }
452
453    // Override the contents of the "from" file with the contents of
454    // the "to" file.
455    SourceMgr.overrideFileContents(FromFile, Buffer);
456  }
457}
458
459/// InitializePreprocessor - Initialize the preprocessor getting it and the
460/// environment ready to process a single file. This returns true on error.
461///
462void clang::InitializePreprocessor(Preprocessor &PP,
463                                   const PreprocessorOptions &InitOpts,
464                                   const HeaderSearchOptions &HSOpts) {
465  std::string PredefineBuffer;
466  PredefineBuffer.reserve(4080);
467  llvm::raw_string_ostream Predefines(PredefineBuffer);
468  MacroBuilder Builder(Predefines);
469
470  InitializeFileRemapping(PP.getDiagnostics(), PP.getSourceManager(),
471                          PP.getFileManager(), InitOpts);
472
473  Builder.append("# 1 \"<built-in>\" 3");
474
475  // Install things like __POWERPC__, __GNUC__, etc into the macro table.
476  if (InitOpts.UsePredefines)
477    InitializePredefinedMacros(PP.getTargetInfo(), PP.getLangOptions(),
478                               Builder);
479
480  // Add on the predefines from the driver.  Wrap in a #line directive to report
481  // that they come from the command line.
482  Builder.append("# 1 \"<command line>\" 1");
483
484  // Process #define's and #undef's in the order they are given.
485  for (unsigned i = 0, e = InitOpts.Macros.size(); i != e; ++i) {
486    if (InitOpts.Macros[i].second)  // isUndef
487      Builder.undefineMacro(InitOpts.Macros[i].first);
488    else
489      DefineBuiltinMacro(Builder, InitOpts.Macros[i].first,
490                         PP.getDiagnostics());
491  }
492
493  // If -imacros are specified, include them now.  These are processed before
494  // any -include directives.
495  for (unsigned i = 0, e = InitOpts.MacroIncludes.size(); i != e; ++i)
496    AddImplicitIncludeMacros(Builder, InitOpts.MacroIncludes[i]);
497
498  // Process -include directives.
499  for (unsigned i = 0, e = InitOpts.Includes.size(); i != e; ++i) {
500    const std::string &Path = InitOpts.Includes[i];
501    if (Path == InitOpts.ImplicitPTHInclude)
502      AddImplicitIncludePTH(Builder, PP, Path);
503    else
504      AddImplicitInclude(Builder, Path);
505  }
506
507  // Exit the command line and go back to <built-in> (2 is LC_LEAVE).
508  Builder.append("# 1 \"<built-in>\" 2");
509
510  // Copy PredefinedBuffer into the Preprocessor.
511  PP.setPredefines(Predefines.str());
512
513  // Initialize the header search object.
514  ApplyHeaderSearchOptions(PP.getHeaderSearchInfo(), HSOpts,
515                           PP.getLangOptions(),
516                           PP.getTargetInfo().getTriple());
517}
518