contrib/llvm/tools/clang/lib/Frontend/InitHeaderSearch.cpp

   1 //===--- InitHeaderSearch.cpp - Initialize header search paths ------------===//
   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 InitHeaderSearch class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "clang/Frontend/Utils.h"
  15 #include "clang/Basic/FileManager.h"
  16 #include "clang/Basic/LangOptions.h"
  17 #include "clang/Basic/Version.h"
  18 #include "clang/Frontend/HeaderSearchOptions.h"
  19 #include "clang/Lex/HeaderSearch.h"
  20 #include "llvm/ADT/SmallString.h"
  21 #include "llvm/ADT/SmallPtrSet.h"
  22 #include "llvm/ADT/SmallVector.h"
  23 #include "llvm/ADT/StringExtras.h"
  24 #include "llvm/ADT/Triple.h"
  25 #include "llvm/ADT/Twine.h"
  26 #include "llvm/Support/raw_ostream.h"
  27 #include "llvm/Support/ErrorHandling.h"
  28 #include "llvm/Support/Path.h"
  29
  30 #include "clang/Config/config.h" // C_INCLUDE_DIRS
  31
  32 using namespace clang;
  33 using namespace clang::frontend;
  34
  35 namespace {
  36
  37 /// InitHeaderSearch - This class makes it easier to set the search paths of
  38 ///  a HeaderSearch object. InitHeaderSearch stores several search path lists
  39 ///  internally, which can be sent to a HeaderSearch object in one swoop.
  40 class InitHeaderSearch {
  41   std::vector<std::pair<IncludeDirGroup, DirectoryLookup> > IncludePath;
  42   typedef std::vector<std::pair<IncludeDirGroup,
  43                       DirectoryLookup> >::const_iterator path_iterator;
  44   HeaderSearch &Headers;
  45   bool Verbose;
  46   std::string IncludeSysroot;
  47   bool IsNotEmptyOrRoot;
  48
  49 public:
  50
  51   InitHeaderSearch(HeaderSearch &HS, bool verbose, StringRef sysroot)
  52     : Headers(HS), Verbose(verbose), IncludeSysroot(sysroot),
  53       IsNotEmptyOrRoot(!(sysroot.empty() || sysroot == "/")) {
  54   }
  55
  56   /// AddPath - Add the specified path to the specified group list.
  57   void AddPath(const Twine &Path, IncludeDirGroup Group,
  58                bool isCXXAware, bool isUserSupplied,
  59                bool isFramework, bool IgnoreSysRoot = false);
  60
  61   /// AddGnuCPlusPlusIncludePaths - Add the necessary paths to support a gnu
  62   ///  libstdc++.
  63   void AddGnuCPlusPlusIncludePaths(StringRef Base,
  64                                    StringRef ArchDir,
  65                                    StringRef Dir32,
  66                                    StringRef Dir64,
  67                                    const llvm::Triple &triple);
  68
  69   /// AddMinGWCPlusPlusIncludePaths - Add the necessary paths to support a MinGW
  70   ///  libstdc++.
  71   void AddMinGWCPlusPlusIncludePaths(StringRef Base,
  72                                      StringRef Arch,
  73                                      StringRef Version);
  74
  75   /// AddMinGW64CXXPaths - Add the necessary paths to support
  76   /// libstdc++ of x86_64-w64-mingw32 aka mingw-w64.
  77   void AddMinGW64CXXPaths(StringRef Base,
  78                           StringRef Version);
  79
  80   // AddDefaultCIncludePaths - Add paths that should always be searched.
  81   void AddDefaultCIncludePaths(const llvm::Triple &triple,
  82                                const HeaderSearchOptions &HSOpts);
  83
  84   // AddDefaultCPlusPlusIncludePaths -  Add paths that should be searched when
  85   //  compiling c++.
  86   void AddDefaultCPlusPlusIncludePaths(const llvm::Triple &triple,
  87                                        const HeaderSearchOptions &HSOpts);
  88
  89   /// AddDefaultSystemIncludePaths - Adds the default system include paths so
  90   ///  that e.g. stdio.h is found.
  91   void AddDefaultIncludePaths(const LangOptions &Lang,
  92                               const llvm::Triple &triple,
  93                               const HeaderSearchOptions &HSOpts);
  94
  95   /// Realize - Merges all search path lists into one list and send it to
  96   /// HeaderSearch.
  97   void Realize(const LangOptions &Lang);
  98 };
  99
 100 }  // end anonymous namespace.
 101
 102 void InitHeaderSearch::AddPath(const Twine &Path,
 103                                IncludeDirGroup Group, bool isCXXAware,
 104                                bool isUserSupplied, bool isFramework,
 105                                bool IgnoreSysRoot) {
 106   assert(!Path.isTriviallyEmpty() && "can't handle empty path here");
 107   FileManager &FM = Headers.getFileMgr();
 108
 109   // Compute the actual path, taking into consideration -isysroot.
 110   SmallString<256> MappedPathStorage;
 111   StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
 112
 113   // Handle isysroot.
 114   if ((Group == System || Group == CXXSystem) && !IgnoreSysRoot &&
 115 #if defined(_WIN32)
 116       !MappedPathStr.empty() &&
 117       llvm::sys::path::is_separator(MappedPathStr[0]) &&
 118 #else
 119       llvm::sys::path::is_absolute(MappedPathStr) &&
 120 #endif
 121       IsNotEmptyOrRoot) {
 122     MappedPathStorage.clear();
 123     MappedPathStr =
 124       (IncludeSysroot + Path).toStringRef(MappedPathStorage);
 125   }
 126
 127   // Compute the DirectoryLookup type.
 128   SrcMgr::CharacteristicKind Type;
 129   if (Group == Quoted || Group == Angled || Group == IndexHeaderMap)
 130     Type = SrcMgr::C_User;
 131   else if (isCXXAware)
 132     Type = SrcMgr::C_System;
 133   else
 134     Type = SrcMgr::C_ExternCSystem;
 135
 136
 137   // If the directory exists, add it.
 138   if (const DirectoryEntry *DE = FM.getDirectory(MappedPathStr)) {
 139     IncludePath.push_back(std::make_pair(Group, DirectoryLookup(DE, Type,
 140                           isUserSupplied, isFramework)));
 141     return;
 142   }
 143
 144   // Check to see if this is an apple-style headermap (which are not allowed to
 145   // be frameworks).
 146   if (!isFramework) {
 147     if (const FileEntry *FE = FM.getFile(MappedPathStr)) {
 148       if (const HeaderMap *HM = Headers.CreateHeaderMap(FE)) {
 149         // It is a headermap, add it to the search path.
 150         IncludePath.push_back(std::make_pair(Group, DirectoryLookup(HM, Type,
 151                               isUserSupplied, Group == IndexHeaderMap)));
 152         return;
 153       }
 154     }
 155   }
 156
 157   if (Verbose)
 158     llvm::errs() << "ignoring nonexistent directory \""
 159                  << MappedPathStr << "\"\n";
 160 }
 161
 162 void InitHeaderSearch::AddGnuCPlusPlusIncludePaths(StringRef Base,
 163                                                    StringRef ArchDir,
 164                                                    StringRef Dir32,
 165                                                    StringRef Dir64,
 166                                                    const llvm::Triple &triple) {
 167   // Add the base dir
 168   AddPath(Base, CXXSystem, true, false, false);
 169
 170   // Add the multilib dirs
 171   llvm::Triple::ArchType arch = triple.getArch();
 172   bool is64bit = arch == llvm::Triple::ppc64 || arch == llvm::Triple::x86_64;
 173   if (is64bit)
 174     AddPath(Base + "/" + ArchDir + "/" + Dir64, CXXSystem, true, false, false);
 175   else
 176     AddPath(Base + "/" + ArchDir + "/" + Dir32, CXXSystem, true, false, false);
 177
 178   // Add the backward dir
 179   AddPath(Base + "/backward", CXXSystem, true, false, false);
 180 }
 181
 182 void InitHeaderSearch::AddMinGWCPlusPlusIncludePaths(StringRef Base,
 183                                                      StringRef Arch,
 184                                                      StringRef Version) {
 185   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++",
 186           CXXSystem, true, false, false);
 187   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/" + Arch,
 188           CXXSystem, true, false, false);
 189   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/backward",
 190           CXXSystem, true, false, false);
 191 }
 192
 193 void InitHeaderSearch::AddMinGW64CXXPaths(StringRef Base,
 194                                           StringRef Version) {
 195   // Assumes Base is HeaderSearchOpts' ResourceDir
 196   AddPath(Base + "/../../../include/c++/" + Version,
 197           CXXSystem, true, false, false);
 198   AddPath(Base + "/../../../include/c++/" + Version + "/x86_64-w64-mingw32",
 199           CXXSystem, true, false, false);
 200   AddPath(Base + "/../../../include/c++/" + Version + "/i686-w64-mingw32",
 201           CXXSystem, true, false, false);
 202   AddPath(Base + "/../../../include/c++/" + Version + "/backward",
 203           CXXSystem, true, false, false);
 204 }
 205
 206 void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
 207                                             const HeaderSearchOptions &HSOpts) {
 208   llvm::Triple::OSType os = triple.getOS();
 209
 210   if (HSOpts.UseStandardSystemIncludes) {
 211     switch (os) {
 212     case llvm::Triple::FreeBSD:
 213     case llvm::Triple::NetBSD:
 214       break;
 215     default:
 216       // FIXME: temporary hack: hard-coded paths.
 217       AddPath("/usr/local/include", System, true, false, false);
 218       break;
 219     }
 220   }
 221
 222   // Builtin includes use #include_next directives and should be positioned
 223   // just prior C include dirs.
 224   if (HSOpts.UseBuiltinIncludes) {
 225     // Ignore the sys root, we *always* look for clang headers relative to
 226     // supplied path.
 227     llvm::sys::Path P(HSOpts.ResourceDir);
 228     P.appendComponent("include");
 229     AddPath(P.str(), System, false, false, false, /*IgnoreSysRoot=*/ true);
 230   }
 231
 232   // All remaining additions are for system include directories, early exit if
 233   // we aren't using them.
 234   if (!HSOpts.UseStandardSystemIncludes)
 235     return;
 236
 237   // Add dirs specified via 'configure --with-c-include-dirs'.
 238   StringRef CIncludeDirs(C_INCLUDE_DIRS);
 239   if (CIncludeDirs != "") {
 240     SmallVector<StringRef, 5> dirs;
 241     CIncludeDirs.split(dirs, ":");
 242     for (SmallVectorImpl<StringRef>::iterator i = dirs.begin();
 243          i != dirs.end();
 244          ++i)
 245       AddPath(*i, System, false, false, false);
 246     return;
 247   }
 248
 249   switch (os) {
 250   case llvm::Triple::Linux:
 251   case llvm::Triple::Win32:
 252     llvm_unreachable("Include management is handled in the driver.");
 253
 254   case llvm::Triple::Haiku:
 255     AddPath("/boot/common/include", System, true, false, false);
 256     AddPath("/boot/develop/headers/os", System, true, false, false);
 257     AddPath("/boot/develop/headers/os/app", System, true, false, false);
 258     AddPath("/boot/develop/headers/os/arch", System, true, false, false);
 259     AddPath("/boot/develop/headers/os/device", System, true, false, false);
 260     AddPath("/boot/develop/headers/os/drivers", System, true, false, false);
 261     AddPath("/boot/develop/headers/os/game", System, true, false, false);
 262     AddPath("/boot/develop/headers/os/interface", System, true, false, false);
 263     AddPath("/boot/develop/headers/os/kernel", System, true, false, false);
 264     AddPath("/boot/develop/headers/os/locale", System, true, false, false);
 265     AddPath("/boot/develop/headers/os/mail", System, true, false, false);
 266     AddPath("/boot/develop/headers/os/media", System, true, false, false);
 267     AddPath("/boot/develop/headers/os/midi", System, true, false, false);
 268     AddPath("/boot/develop/headers/os/midi2", System, true, false, false);
 269     AddPath("/boot/develop/headers/os/net", System, true, false, false);
 270     AddPath("/boot/develop/headers/os/storage", System, true, false, false);
 271     AddPath("/boot/develop/headers/os/support", System, true, false, false);
 272     AddPath("/boot/develop/headers/os/translation",
 273       System, true, false, false);
 274     AddPath("/boot/develop/headers/os/add-ons/graphics",
 275       System, true, false, false);
 276     AddPath("/boot/develop/headers/os/add-ons/input_server",
 277       System, true, false, false);
 278     AddPath("/boot/develop/headers/os/add-ons/screen_saver",
 279       System, true, false, false);
 280     AddPath("/boot/develop/headers/os/add-ons/tracker",
 281       System, true, false, false);
 282     AddPath("/boot/develop/headers/os/be_apps/Deskbar",
 283       System, true, false, false);
 284     AddPath("/boot/develop/headers/os/be_apps/NetPositive",
 285       System, true, false, false);
 286     AddPath("/boot/develop/headers/os/be_apps/Tracker",
 287       System, true, false, false);
 288     AddPath("/boot/develop/headers/cpp", System, true, false, false);
 289     AddPath("/boot/develop/headers/cpp/i586-pc-haiku",
 290       System, true, false, false);
 291     AddPath("/boot/develop/headers/3rdparty", System, true, false, false);
 292     AddPath("/boot/develop/headers/bsd", System, true, false, false);
 293     AddPath("/boot/develop/headers/glibc", System, true, false, false);
 294     AddPath("/boot/develop/headers/posix", System, true, false, false);
 295     AddPath("/boot/develop/headers",  System, true, false, false);
 296     break;
 297   case llvm::Triple::RTEMS:
 298     break;
 299   case llvm::Triple::Cygwin:
 300     AddPath("/usr/include/w32api", System, true, false, false);
 301     break;
 302   case llvm::Triple::MinGW32: {
 303       // mingw-w64 crt include paths
 304       llvm::sys::Path P(HSOpts.ResourceDir);
 305       P.appendComponent("../../../i686-w64-mingw32/include"); // <sysroot>/i686-w64-mingw32/include
 306       AddPath(P.str(), System, true, false, false);
 307       P = llvm::sys::Path(HSOpts.ResourceDir);
 308       P.appendComponent("../../../x86_64-w64-mingw32/include"); // <sysroot>/x86_64-w64-mingw32/include
 309       AddPath(P.str(), System, true, false, false);
 310       // mingw.org crt include paths
 311       P = llvm::sys::Path(HSOpts.ResourceDir);
 312       P.appendComponent("../../../include"); // <sysroot>/include
 313       AddPath(P.str(), System, true, false, false);
 314       AddPath("/mingw/include", System, true, false, false);
 315       AddPath("c:/mingw/include", System, true, false, false);
 316     }
 317     break;
 318   case llvm::Triple::FreeBSD:
 319     AddPath("/usr/include/clang/" CLANG_VERSION_STRING,
 320       System, false, false, false);
 321     break;
 322
 323   default:
 324     break;
 325   }
 326
 327   if ( os != llvm::Triple::RTEMS )
 328     AddPath("/usr/include", System, false, false, false);
 329 }
 330
 331 void InitHeaderSearch::
 332 AddDefaultCPlusPlusIncludePaths(const llvm::Triple &triple, const HeaderSearchOptions &HSOpts) {
 333   llvm::Triple::OSType os = triple.getOS();
 334   // FIXME: temporary hack: hard-coded paths.
 335
 336   if (triple.isOSDarwin()) {
 337     switch (triple.getArch()) {
 338     default: break;
 339
 340     case llvm::Triple::ppc:
 341     case llvm::Triple::ppc64:
 342       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
 343                                   "powerpc-apple-darwin10", "", "ppc64",
 344                                   triple);
 345       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.0.0",
 346                                   "powerpc-apple-darwin10", "", "ppc64",
 347                                   triple);
 348       break;
 349
 350     case llvm::Triple::x86:
 351     case llvm::Triple::x86_64:
 352       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
 353                                   "i686-apple-darwin10", "", "x86_64", triple);
 354       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.0.0",
 355                                   "i686-apple-darwin8", "", "", triple);
 356       break;
 357
 358     case llvm::Triple::arm:
 359     case llvm::Triple::thumb:
 360       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
 361                                   "arm-apple-darwin10", "v7", "", triple);
 362       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
 363                                   "arm-apple-darwin10", "v6", "", triple);
 364       break;
 365     }
 366     return;
 367   }
 368
 369   switch (os) {
 370   case llvm::Triple::Linux:
 371   case llvm::Triple::Win32:
 372     llvm_unreachable("Include management is handled in the driver.");
 373
 374   case llvm::Triple::Cygwin:
 375     // Cygwin-1.7
 376     AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.5.3");
 377     AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.4");
 378     // g++-4 / Cygwin-1.5
 379     AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
 380     break;
 381   case llvm::Triple::MinGW32:
 382     // mingw-w64 C++ include paths (i686-w64-mingw32 and x86_64-w64-mingw32)
 383     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.0");
 384     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.1");
 385     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.2");
 386     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.3");
 387     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.5.4");
 388     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.0");
 389     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.1");
 390     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.2");
 391     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.6.3");
 392     AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.7.0");
 393     // mingw.org C++ include paths
 394     AddMinGWCPlusPlusIncludePaths("/mingw/lib/gcc", "mingw32", "4.5.2"); //MSYS
 395     AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.6.2");
 396     AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.6.1");
 397     AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.5.2");
 398     AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.5.0");
 399     AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.4.0");
 400     AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.3.0");
 401     break;
 402   case llvm::Triple::DragonFly:
 403     AddPath("/usr/include/c++/4.1", CXXSystem, true, false, false);
 404     break;
 405   case llvm::Triple::FreeBSD:
 406     // FreeBSD 8.0
 407     // FreeBSD 7.3
 408     AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2", "", "", "", triple);
 409     AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2/backward",
 410                                 "", "", "", triple);
 411     break;
 412   case llvm::Triple::NetBSD:
 413     AddGnuCPlusPlusIncludePaths("/usr/include/g++", "", "", "", triple);
 414     break;
 415   case llvm::Triple::OpenBSD: {
 416     std::string t = triple.getTriple();
 417     if (t.substr(0, 6) == "x86_64")
 418       t.replace(0, 6, "amd64");
 419     AddGnuCPlusPlusIncludePaths("/usr/include/g++",
 420                                 t, "", "", triple);
 421     break;
 422   }
 423   case llvm::Triple::Minix:
 424     AddGnuCPlusPlusIncludePaths("/usr/gnu/include/c++/4.4.3",
 425                                 "", "", "", triple);
 426     break;
 427   case llvm::Triple::Solaris:
 428     AddGnuCPlusPlusIncludePaths("/usr/gcc/4.5/include/c++/4.5.2/",
 429                                 "i386-pc-solaris2.11", "", "", triple);
 430     // Solaris - Fall though..
 431   case llvm::Triple::AuroraUX:
 432     // AuroraUX
 433     AddGnuCPlusPlusIncludePaths("/opt/gcc4/include/c++/4.2.4",
 434                                 "i386-pc-solaris2.11", "", "", triple);
 435     break;
 436   default:
 437     break;
 438   }
 439 }
 440
 441 void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
 442                                               const llvm::Triple &triple,
 443                                             const HeaderSearchOptions &HSOpts) {
 444   // NB: This code path is going away. All of the logic is moving into the
 445   // driver which has the information necessary to do target-specific
 446   // selections of default include paths. Each target which moves there will be
 447   // exempted from this logic here until we can delete the entire pile of code.
 448   switch (triple.getOS()) {
 449   default:
 450     break; // Everything else continues to use this routine's logic.
 451
 452   case llvm::Triple::Linux:
 453   case llvm::Triple::Win32:
 454     return;
 455   }
 456
 457   if (Lang.CPlusPlus && HSOpts.UseStandardCXXIncludes &&
 458       HSOpts.UseStandardSystemIncludes) {
 459     if (HSOpts.UseLibcxx) {
 460       if (triple.isOSDarwin()) {
 461         // On Darwin, libc++ may be installed alongside the compiler in
 462         // lib/c++/v1.
 463         llvm::sys::Path P(HSOpts.ResourceDir);
 464         if (!P.isEmpty()) {
 465           P.eraseComponent();  // Remove version from foo/lib/clang/version
 466           P.eraseComponent();  // Remove clang from foo/lib/clang
 467
 468           // Get foo/lib/c++/v1
 469           P.appendComponent("c++");
 470           P.appendComponent("v1");
 471           AddPath(P.str(), CXXSystem, true, false, false, true);
 472         }
 473       }
 474       // On Solaris, include the support directory for things like xlocale and
 475       // fudged system headers.
 476       if (triple.getOS() == llvm::Triple::Solaris)
 477         AddPath("/usr/include/c++/v1/support/solaris", CXXSystem, true, false,
 478             false);
 479
 480       AddPath("/usr/include/c++/v1", CXXSystem, true, false, false);
 481     } else {
 482       AddDefaultCPlusPlusIncludePaths(triple, HSOpts);
 483     }
 484   }
 485
 486   AddDefaultCIncludePaths(triple, HSOpts);
 487
 488   // Add the default framework include paths on Darwin.
 489   if (HSOpts.UseStandardSystemIncludes) {
 490     if (triple.isOSDarwin()) {
 491       AddPath("/System/Library/Frameworks", System, true, false, true);
 492       AddPath("/Library/Frameworks", System, true, false, true);
 493     }
 494   }
 495 }
 496
 497 /// RemoveDuplicates - If there are duplicate directory entries in the specified
 498 /// search list, remove the later (dead) ones.  Returns the number of non-system
 499 /// headers removed, which is used to update NumAngled.
 500 static unsigned RemoveDuplicates(std::vector<DirectoryLookup> &SearchList,
 501                                  unsigned First, bool Verbose) {
 502   llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenDirs;
 503   llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenFrameworkDirs;
 504   llvm::SmallPtrSet<const HeaderMap *, 8> SeenHeaderMaps;
 505   unsigned NonSystemRemoved = 0;
 506   for (unsigned i = First; i != SearchList.size(); ++i) {
 507     unsigned DirToRemove = i;
 508
 509     const DirectoryLookup &CurEntry = SearchList[i];
 510
 511     if (CurEntry.isNormalDir()) {
 512       // If this isn't the first time we've seen this dir, remove it.
 513       if (SeenDirs.insert(CurEntry.getDir()))
 514         continue;
 515     } else if (CurEntry.isFramework()) {
 516       // If this isn't the first time we've seen this framework dir, remove it.
 517       if (SeenFrameworkDirs.insert(CurEntry.getFrameworkDir()))
 518         continue;
 519     } else {
 520       assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
 521       // If this isn't the first time we've seen this headermap, remove it.
 522       if (SeenHeaderMaps.insert(CurEntry.getHeaderMap()))
 523         continue;
 524     }
 525
 526     // If we have a normal #include dir/framework/headermap that is shadowed
 527     // later in the chain by a system include location, we actually want to
 528     // ignore the user's request and drop the user dir... keeping the system
 529     // dir.  This is weird, but required to emulate GCC's search path correctly.
 530     //
 531     // Since dupes of system dirs are rare, just rescan to find the original
 532     // that we're nuking instead of using a DenseMap.
 533     if (CurEntry.getDirCharacteristic() != SrcMgr::C_User) {
 534       // Find the dir that this is the same of.
 535       unsigned FirstDir;
 536       for (FirstDir = 0; ; ++FirstDir) {
 537         assert(FirstDir != i && "Didn't find dupe?");
 538
 539         const DirectoryLookup &SearchEntry = SearchList[FirstDir];
 540
 541         // If these are different lookup types, then they can't be the dupe.
 542         if (SearchEntry.getLookupType() != CurEntry.getLookupType())
 543           continue;
 544
 545         bool isSame;
 546         if (CurEntry.isNormalDir())
 547           isSame = SearchEntry.getDir() == CurEntry.getDir();
 548         else if (CurEntry.isFramework())
 549           isSame = SearchEntry.getFrameworkDir() == CurEntry.getFrameworkDir();
 550         else {
 551           assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
 552           isSame = SearchEntry.getHeaderMap() == CurEntry.getHeaderMap();
 553         }
 554
 555         if (isSame)
 556           break;
 557       }
 558
 559       // If the first dir in the search path is a non-system dir, zap it
 560       // instead of the system one.
 561       if (SearchList[FirstDir].getDirCharacteristic() == SrcMgr::C_User)
 562         DirToRemove = FirstDir;
 563     }
 564
 565     if (Verbose) {
 566       llvm::errs() << "ignoring duplicate directory \""
 567                    << CurEntry.getName() << "\"\n";
 568       if (DirToRemove != i)
 569         llvm::errs() << "  as it is a non-system directory that duplicates "
 570                      << "a system directory\n";
 571     }
 572     if (DirToRemove != i)
 573       ++NonSystemRemoved;
 574
 575     // This is reached if the current entry is a duplicate.  Remove the
 576     // DirToRemove (usually the current dir).
 577     SearchList.erase(SearchList.begin()+DirToRemove);
 578     --i;
 579   }
 580   return NonSystemRemoved;
 581 }
 582
 583
 584 void InitHeaderSearch::Realize(const LangOptions &Lang) {
 585   // Concatenate ANGLE+SYSTEM+AFTER chains together into SearchList.
 586   std::vector<DirectoryLookup> SearchList;
 587   SearchList.reserve(IncludePath.size());
 588
 589   // Quoted arguments go first.
 590   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
 591        it != ie; ++it) {
 592     if (it->first == Quoted)
 593       SearchList.push_back(it->second);
 594   }
 595   // Deduplicate and remember index.
 596   RemoveDuplicates(SearchList, 0, Verbose);
 597   unsigned NumQuoted = SearchList.size();
 598
 599   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
 600        it != ie; ++it) {
 601     if (it->first == Angled || it->first == IndexHeaderMap)
 602       SearchList.push_back(it->second);
 603   }
 604
 605   RemoveDuplicates(SearchList, NumQuoted, Verbose);
 606   unsigned NumAngled = SearchList.size();
 607
 608   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
 609        it != ie; ++it) {
 610     if (it->first == System ||
 611         (!Lang.ObjC1 && !Lang.CPlusPlus && it->first == CSystem)    ||
 612         (/*FIXME !Lang.ObjC1 && */Lang.CPlusPlus  && it->first == CXXSystem)  ||
 613         (Lang.ObjC1  && !Lang.CPlusPlus && it->first == ObjCSystem) ||
 614         (Lang.ObjC1  && Lang.CPlusPlus  && it->first == ObjCXXSystem))
 615       SearchList.push_back(it->second);
 616   }
 617
 618   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
 619        it != ie; ++it) {
 620     if (it->first == After)
 621       SearchList.push_back(it->second);
 622   }
 623
 624   // Remove duplicates across both the Angled and System directories.  GCC does
 625   // this and failing to remove duplicates across these two groups breaks
 626   // #include_next.
 627   unsigned NonSystemRemoved = RemoveDuplicates(SearchList, NumQuoted, Verbose);
 628   NumAngled -= NonSystemRemoved;
 629
 630   bool DontSearchCurDir = false;  // TODO: set to true if -I- is set?
 631   Headers.SetSearchPaths(SearchList, NumQuoted, NumAngled, DontSearchCurDir);
 632
 633   // If verbose, print the list of directories that will be searched.
 634   if (Verbose) {
 635     llvm::errs() << "#include \"...\" search starts here:\n";
 636     for (unsigned i = 0, e = SearchList.size(); i != e; ++i) {
 637       if (i == NumQuoted)
 638         llvm::errs() << "#include <...> search starts here:\n";
 639       const char *Name = SearchList[i].getName();
 640       const char *Suffix;
 641       if (SearchList[i].isNormalDir())
 642         Suffix = "";
 643       else if (SearchList[i].isFramework())
 644         Suffix = " (framework directory)";
 645       else {
 646         assert(SearchList[i].isHeaderMap() && "Unknown DirectoryLookup");
 647         Suffix = " (headermap)";
 648       }
 649       llvm::errs() << " " << Name << Suffix << "\n";
 650     }
 651     llvm::errs() << "End of search list.\n";
 652   }
 653 }
 654
 655 void clang::ApplyHeaderSearchOptions(HeaderSearch &HS,
 656                                      const HeaderSearchOptions &HSOpts,
 657                                      const LangOptions &Lang,
 658                                      const llvm::Triple &Triple) {
 659   InitHeaderSearch Init(HS, HSOpts.Verbose, HSOpts.Sysroot);
 660
 661   // Add the user defined entries.
 662   for (unsigned i = 0, e = HSOpts.UserEntries.size(); i != e; ++i) {
 663     const HeaderSearchOptions::Entry &E = HSOpts.UserEntries[i];
 664     Init.AddPath(E.Path, E.Group, !E.ImplicitExternC, E.IsUserSupplied,
 665                  E.IsFramework, E.IgnoreSysRoot);
 666   }
 667
 668   Init.AddDefaultIncludePaths(Lang, Triple, HSOpts);
 669
 670   if (HSOpts.UseBuiltinIncludes) {
 671     // Set up the builtin include directory in the module map.
 672     llvm::sys::Path P(HSOpts.ResourceDir);
 673     P.appendComponent("include");
 674     if (const DirectoryEntry *Dir = HS.getFileMgr().getDirectory(P.str()))
 675       HS.getModuleMap().setBuiltinIncludeDir(Dir);
 676   }
 677
 678   Init.Realize(Lang);
 679 }