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/Basic/FileManager.h"
  15 #include "clang/Basic/LangOptions.h"
  16 #include "clang/Config/config.h" // C_INCLUDE_DIRS
  17 #include "clang/Frontend/FrontendDiagnostic.h"
  18 #include "clang/Frontend/Utils.h"
  19 #include "clang/Lex/HeaderMap.h"
  20 #include "clang/Lex/HeaderSearch.h"
  21 #include "clang/Lex/HeaderSearchOptions.h"
  22 #include "llvm/ADT/SmallPtrSet.h"
  23 #include "llvm/ADT/SmallString.h"
  24 #include "llvm/ADT/SmallVector.h"
  25 #include "llvm/ADT/StringExtras.h"
  26 #include "llvm/ADT/Triple.h"
  27 #include "llvm/ADT/Twine.h"
  28 #include "llvm/Support/ErrorHandling.h"
  29 #include "llvm/Support/Path.h"
  30 #include "llvm/Support/raw_ostream.h"
  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   std::vector<std::pair<std::string, bool> > SystemHeaderPrefixes;
  45   HeaderSearch &Headers;
  46   bool Verbose;
  47   std::string IncludeSysroot;
  48   bool HasSysroot;
  49
  50 public:
  51
  52   InitHeaderSearch(HeaderSearch &HS, bool verbose, StringRef sysroot)
  53     : Headers(HS), Verbose(verbose), IncludeSysroot(sysroot),
  54       HasSysroot(!(sysroot.empty() || sysroot == "/")) {
  55   }
  56
  57   /// AddPath - Add the specified path to the specified group list, prefixing
  58   /// the sysroot if used.
  59   /// Returns true if the path exists, false if it was ignored.
  60   bool AddPath(const Twine &Path, IncludeDirGroup Group, bool isFramework);
  61
  62   /// AddUnmappedPath - Add the specified path to the specified group list,
  63   /// without performing any sysroot remapping.
  64   /// Returns true if the path exists, false if it was ignored.
  65   bool AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
  66                        bool isFramework);
  67
  68   /// AddSystemHeaderPrefix - Add the specified prefix to the system header
  69   /// prefix list.
  70   void AddSystemHeaderPrefix(StringRef Prefix, bool IsSystemHeader) {
  71     SystemHeaderPrefixes.emplace_back(Prefix, IsSystemHeader);
  72   }
  73
  74   /// AddGnuCPlusPlusIncludePaths - Add the necessary paths to support a gnu
  75   ///  libstdc++.
  76   /// Returns true if the \p Base path was found, false if it does not exist.
  77   bool AddGnuCPlusPlusIncludePaths(StringRef Base, StringRef ArchDir,
  78                                    StringRef Dir32, StringRef Dir64,
  79                                    const llvm::Triple &triple);
  80
  81   /// AddMinGWCPlusPlusIncludePaths - Add the necessary paths to support a MinGW
  82   ///  libstdc++.
  83   void AddMinGWCPlusPlusIncludePaths(StringRef Base,
  84                                      StringRef Arch,
  85                                      StringRef Version);
  86
  87   // AddDefaultCIncludePaths - Add paths that should always be searched.
  88   void AddDefaultCIncludePaths(const llvm::Triple &triple,
  89                                const HeaderSearchOptions &HSOpts);
  90
  91   // AddDefaultCPlusPlusIncludePaths -  Add paths that should be searched when
  92   //  compiling c++.
  93   void AddDefaultCPlusPlusIncludePaths(const LangOptions &LangOpts,
  94                                        const llvm::Triple &triple,
  95                                        const HeaderSearchOptions &HSOpts);
  96
  97   /// AddDefaultSystemIncludePaths - Adds the default system include paths so
  98   ///  that e.g. stdio.h is found.
  99   void AddDefaultIncludePaths(const LangOptions &Lang,
 100                               const llvm::Triple &triple,
 101                               const HeaderSearchOptions &HSOpts);
 102
 103   /// Realize - Merges all search path lists into one list and send it to
 104   /// HeaderSearch.
 105   void Realize(const LangOptions &Lang);
 106 };
 107
 108 }  // end anonymous namespace.
 109
 110 static bool CanPrefixSysroot(StringRef Path) {
 111 #if defined(_WIN32)
 112   return !Path.empty() && llvm::sys::path::is_separator(Path[0]);
 113 #else
 114   return llvm::sys::path::is_absolute(Path);
 115 #endif
 116 }
 117
 118 bool InitHeaderSearch::AddPath(const Twine &Path, IncludeDirGroup Group,
 119                                bool isFramework) {
 120   // Add the path with sysroot prepended, if desired and this is a system header
 121   // group.
 122   if (HasSysroot) {
 123     SmallString<256> MappedPathStorage;
 124     StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
 125     if (CanPrefixSysroot(MappedPathStr)) {
 126       return AddUnmappedPath(IncludeSysroot + Path, Group, isFramework);
 127     }
 128   }
 129
 130   return AddUnmappedPath(Path, Group, isFramework);
 131 }
 132
 133 bool InitHeaderSearch::AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
 134                                        bool isFramework) {
 135   assert(!Path.isTriviallyEmpty() && "can't handle empty path here");
 136
 137   FileManager &FM = Headers.getFileMgr();
 138   SmallString<256> MappedPathStorage;
 139   StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
 140
 141   // Compute the DirectoryLookup type.
 142   SrcMgr::CharacteristicKind Type;
 143   if (Group == Quoted || Group == Angled || Group == IndexHeaderMap) {
 144     Type = SrcMgr::C_User;
 145   } else if (Group == ExternCSystem) {
 146     Type = SrcMgr::C_ExternCSystem;
 147   } else {
 148     Type = SrcMgr::C_System;
 149   }
 150
 151   // If the directory exists, add it.
 152   if (const DirectoryEntry *DE = FM.getDirectory(MappedPathStr)) {
 153     IncludePath.push_back(
 154       std::make_pair(Group, DirectoryLookup(DE, Type, isFramework)));
 155     return true;
 156   }
 157
 158   // Check to see if this is an apple-style headermap (which are not allowed to
 159   // be frameworks).
 160   if (!isFramework) {
 161     if (const FileEntry *FE = FM.getFile(MappedPathStr)) {
 162       if (const HeaderMap *HM = Headers.CreateHeaderMap(FE)) {
 163         // It is a headermap, add it to the search path.
 164         IncludePath.push_back(
 165           std::make_pair(Group,
 166                          DirectoryLookup(HM, Type, Group == IndexHeaderMap)));
 167         return true;
 168       }
 169     }
 170   }
 171
 172   if (Verbose)
 173     llvm::errs() << "ignoring nonexistent directory \""
 174                  << MappedPathStr << "\"\n";
 175   return false;
 176 }
 177
 178 bool InitHeaderSearch::AddGnuCPlusPlusIncludePaths(StringRef Base,
 179                                                    StringRef ArchDir,
 180                                                    StringRef Dir32,
 181                                                    StringRef Dir64,
 182                                                    const llvm::Triple &triple) {
 183   // Add the base dir
 184   bool IsBaseFound = AddPath(Base, CXXSystem, false);
 185
 186   // Add the multilib dirs
 187   llvm::Triple::ArchType arch = triple.getArch();
 188   bool is64bit = arch == llvm::Triple::ppc64 || arch == llvm::Triple::x86_64;
 189   if (is64bit)
 190     AddPath(Base + "/" + ArchDir + "/" + Dir64, CXXSystem, false);
 191   else
 192     AddPath(Base + "/" + ArchDir + "/" + Dir32, CXXSystem, false);
 193
 194   // Add the backward dir
 195   AddPath(Base + "/backward", CXXSystem, false);
 196   return IsBaseFound;
 197 }
 198
 199 void InitHeaderSearch::AddMinGWCPlusPlusIncludePaths(StringRef Base,
 200                                                      StringRef Arch,
 201                                                      StringRef Version) {
 202   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++",
 203           CXXSystem, false);
 204   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/" + Arch,
 205           CXXSystem, false);
 206   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/backward",
 207           CXXSystem, false);
 208 }
 209
 210 void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
 211                                             const HeaderSearchOptions &HSOpts) {
 212   llvm::Triple::OSType os = triple.getOS();
 213
 214   if (HSOpts.UseStandardSystemIncludes) {
 215     switch (os) {
 216     case llvm::Triple::CloudABI:
 217     case llvm::Triple::FreeBSD:
 218     case llvm::Triple::NetBSD:
 219     case llvm::Triple::OpenBSD:
 220     case llvm::Triple::NaCl:
 221     case llvm::Triple::PS4:
 222     case llvm::Triple::ELFIAMCU:
 223     case llvm::Triple::Fuchsia:
 224       break;
 225     case llvm::Triple::Win32:
 226       if (triple.getEnvironment() != llvm::Triple::Cygnus)
 227         break;
 228       LLVM_FALLTHROUGH;
 229     default:
 230       // FIXME: temporary hack: hard-coded paths.
 231       AddPath("/usr/local/include", System, false);
 232       break;
 233     }
 234   }
 235
 236   // Builtin includes use #include_next directives and should be positioned
 237   // just prior C include dirs.
 238   if (HSOpts.UseBuiltinIncludes) {
 239     // Ignore the sys root, we *always* look for clang headers relative to
 240     // supplied path.
 241     SmallString<128> P = StringRef(HSOpts.ResourceDir);
 242     llvm::sys::path::append(P, "include");
 243     AddUnmappedPath(P, ExternCSystem, false);
 244   }
 245
 246   // All remaining additions are for system include directories, early exit if
 247   // we aren't using them.
 248   if (!HSOpts.UseStandardSystemIncludes)
 249     return;
 250
 251   // Add dirs specified via 'configure --with-c-include-dirs'.
 252   StringRef CIncludeDirs(C_INCLUDE_DIRS);
 253   if (CIncludeDirs != "") {
 254     SmallVector<StringRef, 5> dirs;
 255     CIncludeDirs.split(dirs, ":");
 256     for (StringRef dir : dirs)
 257       AddPath(dir, ExternCSystem, false);
 258     return;
 259   }
 260
 261   switch (os) {
 262   case llvm::Triple::Linux:
 263   case llvm::Triple::Solaris:
 264     llvm_unreachable("Include management is handled in the driver.");
 265
 266   case llvm::Triple::CloudABI: {
 267     // <sysroot>/<triple>/include
 268     SmallString<128> P = StringRef(HSOpts.ResourceDir);
 269     llvm::sys::path::append(P, "../../..", triple.str(), "include");
 270     AddPath(P, System, false);
 271     break;
 272   }
 273
 274   case llvm::Triple::Haiku:
 275     AddPath("/boot/system/non-packaged/develop/headers", System, false);
 276     AddPath("/boot/system/develop/headers/os", System, false);
 277     AddPath("/boot/system/develop/headers/os/app", System, false);
 278     AddPath("/boot/system/develop/headers/os/arch", System, false);
 279     AddPath("/boot/system/develop/headers/os/device", System, false);
 280     AddPath("/boot/system/develop/headers/os/drivers", System, false);
 281     AddPath("/boot/system/develop/headers/os/game", System, false);
 282     AddPath("/boot/system/develop/headers/os/interface", System, false);
 283     AddPath("/boot/system/develop/headers/os/kernel", System, false);
 284     AddPath("/boot/system/develop/headers/os/locale", System, false);
 285     AddPath("/boot/system/develop/headers/os/mail", System, false);
 286     AddPath("/boot/system/develop/headers/os/media", System, false);
 287     AddPath("/boot/system/develop/headers/os/midi", System, false);
 288     AddPath("/boot/system/develop/headers/os/midi2", System, false);
 289     AddPath("/boot/system/develop/headers/os/net", System, false);
 290     AddPath("/boot/system/develop/headers/os/opengl", System, false);
 291     AddPath("/boot/system/develop/headers/os/storage", System, false);
 292     AddPath("/boot/system/develop/headers/os/support", System, false);
 293     AddPath("/boot/system/develop/headers/os/translation", System, false);
 294     AddPath("/boot/system/develop/headers/os/add-ons/graphics", System, false);
 295     AddPath("/boot/system/develop/headers/os/add-ons/input_server", System, false);
 296     AddPath("/boot/system/develop/headers/os/add-ons/mail_daemon", System, false);
 297     AddPath("/boot/system/develop/headers/os/add-ons/registrar", System, false);
 298     AddPath("/boot/system/develop/headers/os/add-ons/screen_saver", System, false);
 299     AddPath("/boot/system/develop/headers/os/add-ons/tracker", System, false);
 300     AddPath("/boot/system/develop/headers/os/be_apps/Deskbar", System, false);
 301     AddPath("/boot/system/develop/headers/os/be_apps/NetPositive", System, false);
 302     AddPath("/boot/system/develop/headers/os/be_apps/Tracker", System, false);
 303     AddPath("/boot/system/develop/headers/3rdparty", System, false);
 304     AddPath("/boot/system/develop/headers/bsd", System, false);
 305     AddPath("/boot/system/develop/headers/glibc", System, false);
 306     AddPath("/boot/system/develop/headers/posix", System, false);
 307     AddPath("/boot/system/develop/headers",  System, false);
 308     break;
 309   case llvm::Triple::RTEMS:
 310     break;
 311   case llvm::Triple::Win32:
 312     switch (triple.getEnvironment()) {
 313     default: llvm_unreachable("Include management is handled in the driver.");
 314     case llvm::Triple::Cygnus:
 315       AddPath("/usr/include/w32api", System, false);
 316       break;
 317     case llvm::Triple::GNU:
 318       break;
 319     }
 320     break;
 321   default:
 322     break;
 323   }
 324
 325   switch (os) {
 326   case llvm::Triple::CloudABI:
 327   case llvm::Triple::RTEMS:
 328   case llvm::Triple::NaCl:
 329   case llvm::Triple::ELFIAMCU:
 330   case llvm::Triple::Fuchsia:
 331     break;
 332   case llvm::Triple::PS4: {
 333     // <isysroot> gets prepended later in AddPath().
 334     std::string BaseSDKPath = "";
 335     if (!HasSysroot) {
 336       const char *envValue = getenv("SCE_ORBIS_SDK_DIR");
 337       if (envValue)
 338         BaseSDKPath = envValue;
 339       else {
 340         // HSOpts.ResourceDir variable contains the location of Clang's
 341         // resource files.
 342         // Assuming that Clang is configured for PS4 without
 343         // --with-clang-resource-dir option, the location of Clang's resource
 344         // files is <SDK_DIR>/host_tools/lib/clang
 345         SmallString<128> P = StringRef(HSOpts.ResourceDir);
 346         llvm::sys::path::append(P, "../../..");
 347         BaseSDKPath = P.str();
 348       }
 349     }
 350     AddPath(BaseSDKPath + "/target/include", System, false);
 351     if (triple.isPS4CPU())
 352       AddPath(BaseSDKPath + "/target/include_common", System, false);
 353     LLVM_FALLTHROUGH;
 354   }
 355   default:
 356     AddPath("/usr/include", ExternCSystem, false);
 357     break;
 358   }
 359 }
 360
 361 void InitHeaderSearch::AddDefaultCPlusPlusIncludePaths(
 362     const LangOptions &LangOpts, const llvm::Triple &triple,
 363     const HeaderSearchOptions &HSOpts) {
 364   llvm::Triple::OSType os = triple.getOS();
 365   // FIXME: temporary hack: hard-coded paths.
 366
 367   if (triple.isOSDarwin()) {
 368     bool IsBaseFound = true;
 369     switch (triple.getArch()) {
 370     default: break;
 371
 372     case llvm::Triple::ppc:
 373     case llvm::Triple::ppc64:
 374       IsBaseFound = AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
 375                                                 "powerpc-apple-darwin10", "",
 376                                                 "ppc64", triple);
 377       IsBaseFound |= AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.0.0",
 378                                                  "powerpc-apple-darwin10", "",
 379                                                  "ppc64", triple);
 380       break;
 381
 382     case llvm::Triple::x86:
 383     case llvm::Triple::x86_64:
 384       IsBaseFound = AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
 385                                                 "i686-apple-darwin10", "",
 386                                                 "x86_64", triple);
 387       IsBaseFound |= AddGnuCPlusPlusIncludePaths(
 388           "/usr/include/c++/4.0.0", "i686-apple-darwin8", "", "", triple);
 389       break;
 390
 391     case llvm::Triple::arm:
 392     case llvm::Triple::thumb:
 393       IsBaseFound = AddGnuCPlusPlusIncludePaths(
 394           "/usr/include/c++/4.2.1", "arm-apple-darwin10", "v7", "", triple);
 395       IsBaseFound |= AddGnuCPlusPlusIncludePaths(
 396           "/usr/include/c++/4.2.1", "arm-apple-darwin10", "v6", "", triple);
 397       break;
 398
 399     case llvm::Triple::aarch64:
 400       IsBaseFound = AddGnuCPlusPlusIncludePaths(
 401           "/usr/include/c++/4.2.1", "arm64-apple-darwin10", "", "", triple);
 402       break;
 403     }
 404     // Warn when compiling pure C++ / Objective-C++ only.
 405     if (!IsBaseFound &&
 406         !(LangOpts.CUDA || LangOpts.OpenCL || LangOpts.RenderScript)) {
 407       Headers.getDiags().Report(SourceLocation(),
 408                                 diag::warn_stdlibcxx_not_found);
 409     }
 410     return;
 411   }
 412
 413   switch (os) {
 414   case llvm::Triple::Linux:
 415   case llvm::Triple::Solaris:
 416     llvm_unreachable("Include management is handled in the driver.");
 417     break;
 418   case llvm::Triple::Win32:
 419     switch (triple.getEnvironment()) {
 420     default: llvm_unreachable("Include management is handled in the driver.");
 421     case llvm::Triple::Cygnus:
 422       // Cygwin-1.7
 423       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.7.3");
 424       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.5.3");
 425       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.4");
 426       // g++-4 / Cygwin-1.5
 427       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
 428       break;
 429     }
 430     break;
 431   case llvm::Triple::DragonFly:
 432     AddPath("/usr/include/c++/5.0", CXXSystem, false);
 433     break;
 434   case llvm::Triple::OpenBSD: {
 435     std::string t = triple.getTriple();
 436     if (t.substr(0, 6) == "x86_64")
 437       t.replace(0, 6, "amd64");
 438     AddGnuCPlusPlusIncludePaths("/usr/include/g++",
 439                                 t, "", "", triple);
 440     break;
 441   }
 442   case llvm::Triple::Minix:
 443     AddGnuCPlusPlusIncludePaths("/usr/gnu/include/c++/4.4.3",
 444                                 "", "", "", triple);
 445     break;
 446   default:
 447     break;
 448   }
 449 }
 450
 451 void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
 452                                               const llvm::Triple &triple,
 453                                             const HeaderSearchOptions &HSOpts) {
 454   // NB: This code path is going away. All of the logic is moving into the
 455   // driver which has the information necessary to do target-specific
 456   // selections of default include paths. Each target which moves there will be
 457   // exempted from this logic here until we can delete the entire pile of code.
 458   switch (triple.getOS()) {
 459   default:
 460     break; // Everything else continues to use this routine's logic.
 461
 462   case llvm::Triple::Linux:
 463   case llvm::Triple::Solaris:
 464     return;
 465
 466   case llvm::Triple::Win32:
 467     if (triple.getEnvironment() != llvm::Triple::Cygnus ||
 468         triple.isOSBinFormatMachO())
 469       return;
 470     break;
 471   }
 472
 473   if (Lang.CPlusPlus && !Lang.AsmPreprocessor &&
 474       HSOpts.UseStandardCXXIncludes && HSOpts.UseStandardSystemIncludes) {
 475     if (HSOpts.UseLibcxx) {
 476       if (triple.isOSDarwin()) {
 477         // On Darwin, libc++ may be installed alongside the compiler in
 478         // include/c++/v1.
 479         if (!HSOpts.ResourceDir.empty()) {
 480           // Remove version from foo/lib/clang/version
 481           StringRef NoVer = llvm::sys::path::parent_path(HSOpts.ResourceDir);
 482           // Remove clang from foo/lib/clang
 483           StringRef Lib = llvm::sys::path::parent_path(NoVer);
 484           // Remove lib from foo/lib
 485           SmallString<128> P = llvm::sys::path::parent_path(Lib);
 486
 487           // Get foo/include/c++/v1
 488           llvm::sys::path::append(P, "include", "c++", "v1");
 489           AddUnmappedPath(P, CXXSystem, false);
 490         }
 491       }
 492       AddPath("/usr/include/c++/v1", CXXSystem, false);
 493     } else {
 494       AddDefaultCPlusPlusIncludePaths(Lang, triple, HSOpts);
 495     }
 496   }
 497
 498   AddDefaultCIncludePaths(triple, HSOpts);
 499
 500   // Add the default framework include paths on Darwin.
 501   if (HSOpts.UseStandardSystemIncludes) {
 502     if (triple.isOSDarwin()) {
 503       AddPath("/System/Library/Frameworks", System, true);
 504       AddPath("/Library/Frameworks", System, true);
 505     }
 506   }
 507 }
 508
 509 /// RemoveDuplicates - If there are duplicate directory entries in the specified
 510 /// search list, remove the later (dead) ones.  Returns the number of non-system
 511 /// headers removed, which is used to update NumAngled.
 512 static unsigned RemoveDuplicates(std::vector<DirectoryLookup> &SearchList,
 513                                  unsigned First, bool Verbose) {
 514   llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenDirs;
 515   llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenFrameworkDirs;
 516   llvm::SmallPtrSet<const HeaderMap *, 8> SeenHeaderMaps;
 517   unsigned NonSystemRemoved = 0;
 518   for (unsigned i = First; i != SearchList.size(); ++i) {
 519     unsigned DirToRemove = i;
 520
 521     const DirectoryLookup &CurEntry = SearchList[i];
 522
 523     if (CurEntry.isNormalDir()) {
 524       // If this isn't the first time we've seen this dir, remove it.
 525       if (SeenDirs.insert(CurEntry.getDir()).second)
 526         continue;
 527     } else if (CurEntry.isFramework()) {
 528       // If this isn't the first time we've seen this framework dir, remove it.
 529       if (SeenFrameworkDirs.insert(CurEntry.getFrameworkDir()).second)
 530         continue;
 531     } else {
 532       assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
 533       // If this isn't the first time we've seen this headermap, remove it.
 534       if (SeenHeaderMaps.insert(CurEntry.getHeaderMap()).second)
 535         continue;
 536     }
 537
 538     // If we have a normal #include dir/framework/headermap that is shadowed
 539     // later in the chain by a system include location, we actually want to
 540     // ignore the user's request and drop the user dir... keeping the system
 541     // dir.  This is weird, but required to emulate GCC's search path correctly.
 542     //
 543     // Since dupes of system dirs are rare, just rescan to find the original
 544     // that we're nuking instead of using a DenseMap.
 545     if (CurEntry.getDirCharacteristic() != SrcMgr::C_User) {
 546       // Find the dir that this is the same of.
 547       unsigned FirstDir;
 548       for (FirstDir = First;; ++FirstDir) {
 549         assert(FirstDir != i && "Didn't find dupe?");
 550
 551         const DirectoryLookup &SearchEntry = SearchList[FirstDir];
 552
 553         // If these are different lookup types, then they can't be the dupe.
 554         if (SearchEntry.getLookupType() != CurEntry.getLookupType())
 555           continue;
 556
 557         bool isSame;
 558         if (CurEntry.isNormalDir())
 559           isSame = SearchEntry.getDir() == CurEntry.getDir();
 560         else if (CurEntry.isFramework())
 561           isSame = SearchEntry.getFrameworkDir() == CurEntry.getFrameworkDir();
 562         else {
 563           assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
 564           isSame = SearchEntry.getHeaderMap() == CurEntry.getHeaderMap();
 565         }
 566
 567         if (isSame)
 568           break;
 569       }
 570
 571       // If the first dir in the search path is a non-system dir, zap it
 572       // instead of the system one.
 573       if (SearchList[FirstDir].getDirCharacteristic() == SrcMgr::C_User)
 574         DirToRemove = FirstDir;
 575     }
 576
 577     if (Verbose) {
 578       llvm::errs() << "ignoring duplicate directory \""
 579                    << CurEntry.getName() << "\"\n";
 580       if (DirToRemove != i)
 581         llvm::errs() << "  as it is a non-system directory that duplicates "
 582                      << "a system directory\n";
 583     }
 584     if (DirToRemove != i)
 585       ++NonSystemRemoved;
 586
 587     // This is reached if the current entry is a duplicate.  Remove the
 588     // DirToRemove (usually the current dir).
 589     SearchList.erase(SearchList.begin()+DirToRemove);
 590     --i;
 591   }
 592   return NonSystemRemoved;
 593 }
 594
 595
 596 void InitHeaderSearch::Realize(const LangOptions &Lang) {
 597   // Concatenate ANGLE+SYSTEM+AFTER chains together into SearchList.
 598   std::vector<DirectoryLookup> SearchList;
 599   SearchList.reserve(IncludePath.size());
 600
 601   // Quoted arguments go first.
 602   for (auto &Include : IncludePath)
 603     if (Include.first == Quoted)
 604       SearchList.push_back(Include.second);
 605
 606   // Deduplicate and remember index.
 607   RemoveDuplicates(SearchList, 0, Verbose);
 608   unsigned NumQuoted = SearchList.size();
 609
 610   for (auto &Include : IncludePath)
 611     if (Include.first == Angled || Include.first == IndexHeaderMap)
 612       SearchList.push_back(Include.second);
 613
 614   RemoveDuplicates(SearchList, NumQuoted, Verbose);
 615   unsigned NumAngled = SearchList.size();
 616
 617   for (auto &Include : IncludePath)
 618     if (Include.first == System || Include.first == ExternCSystem ||
 619         (!Lang.ObjC1 && !Lang.CPlusPlus && Include.first == CSystem) ||
 620         (/*FIXME !Lang.ObjC1 && */ Lang.CPlusPlus &&
 621          Include.first == CXXSystem) ||
 622         (Lang.ObjC1 && !Lang.CPlusPlus && Include.first == ObjCSystem) ||
 623         (Lang.ObjC1 && Lang.CPlusPlus && Include.first == ObjCXXSystem))
 624       SearchList.push_back(Include.second);
 625
 626   for (auto &Include : IncludePath)
 627     if (Include.first == After)
 628       SearchList.push_back(Include.second);
 629
 630   // Remove duplicates across both the Angled and System directories.  GCC does
 631   // this and failing to remove duplicates across these two groups breaks
 632   // #include_next.
 633   unsigned NonSystemRemoved = RemoveDuplicates(SearchList, NumQuoted, Verbose);
 634   NumAngled -= NonSystemRemoved;
 635
 636   bool DontSearchCurDir = false;  // TODO: set to true if -I- is set?
 637   Headers.SetSearchPaths(SearchList, NumQuoted, NumAngled, DontSearchCurDir);
 638
 639   Headers.SetSystemHeaderPrefixes(SystemHeaderPrefixes);
 640
 641   // If verbose, print the list of directories that will be searched.
 642   if (Verbose) {
 643     llvm::errs() << "#include \"...\" search starts here:\n";
 644     for (unsigned i = 0, e = SearchList.size(); i != e; ++i) {
 645       if (i == NumQuoted)
 646         llvm::errs() << "#include <...> search starts here:\n";
 647       StringRef Name = SearchList[i].getName();
 648       const char *Suffix;
 649       if (SearchList[i].isNormalDir())
 650         Suffix = "";
 651       else if (SearchList[i].isFramework())
 652         Suffix = " (framework directory)";
 653       else {
 654         assert(SearchList[i].isHeaderMap() && "Unknown DirectoryLookup");
 655         Suffix = " (headermap)";
 656       }
 657       llvm::errs() << " " << Name << Suffix << "\n";
 658     }
 659     llvm::errs() << "End of search list.\n";
 660   }
 661 }
 662
 663 void clang::ApplyHeaderSearchOptions(HeaderSearch &HS,
 664                                      const HeaderSearchOptions &HSOpts,
 665                                      const LangOptions &Lang,
 666                                      const llvm::Triple &Triple) {
 667   InitHeaderSearch Init(HS, HSOpts.Verbose, HSOpts.Sysroot);
 668
 669   // Add the user defined entries.
 670   for (unsigned i = 0, e = HSOpts.UserEntries.size(); i != e; ++i) {
 671     const HeaderSearchOptions::Entry &E = HSOpts.UserEntries[i];
 672     if (E.IgnoreSysRoot) {
 673       Init.AddUnmappedPath(E.Path, E.Group, E.IsFramework);
 674     } else {
 675       Init.AddPath(E.Path, E.Group, E.IsFramework);
 676     }
 677   }
 678
 679   Init.AddDefaultIncludePaths(Lang, Triple, HSOpts);
 680
 681   for (unsigned i = 0, e = HSOpts.SystemHeaderPrefixes.size(); i != e; ++i)
 682     Init.AddSystemHeaderPrefix(HSOpts.SystemHeaderPrefixes[i].Prefix,
 683                                HSOpts.SystemHeaderPrefixes[i].IsSystemHeader);
 684
 685   if (HSOpts.UseBuiltinIncludes) {
 686     // Set up the builtin include directory in the module map.
 687     SmallString<128> P = StringRef(HSOpts.ResourceDir);
 688     llvm::sys::path::append(P, "include");
 689     if (const DirectoryEntry *Dir = HS.getFileMgr().getDirectory(P))
 690       HS.getModuleMap().setBuiltinIncludeDir(Dir);
 691   }
 692
 693   Init.Realize(Lang);
 694 }