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/Config/config.h" // C_INCLUDE_DIRS
18 #include "clang/Lex/HeaderSearch.h"
19 #include "clang/Lex/HeaderSearchOptions.h"
20 #include "llvm/ADT/SmallPtrSet.h"
21 #include "llvm/ADT/SmallString.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/ErrorHandling.h"
27 #include "llvm/Support/FileSystem.h"
28 #include "llvm/Support/Path.h"
29 #include "llvm/Support/raw_ostream.h"
30 
31 using namespace clang;
32 using namespace clang::frontend;
33 
34 namespace {
35 
36 /// InitHeaderSearch - This class makes it easier to set the search paths of
37 ///  a HeaderSearch object. InitHeaderSearch stores several search path lists
38 ///  internally, which can be sent to a HeaderSearch object in one swoop.
39 class InitHeaderSearch {
40   std::vector<std::pair<IncludeDirGroup, DirectoryLookup> > IncludePath;
41   typedef std::vector<std::pair<IncludeDirGroup,
42                       DirectoryLookup> >::const_iterator path_iterator;
43   std::vector<std::pair<std::string, bool> > SystemHeaderPrefixes;
44   HeaderSearch &Headers;
45   bool Verbose;
46   std::string IncludeSysroot;
47   bool HasSysroot;
48 
49 public:
50 
51   InitHeaderSearch(HeaderSearch &HS, bool verbose, StringRef sysroot)
52     : Headers(HS), Verbose(verbose), IncludeSysroot(sysroot),
53       HasSysroot(!(sysroot.empty() || sysroot == "/")) {
54   }
55 
56   /// AddPath - Add the specified path to the specified group list, prefixing
57   /// the sysroot if used.
58   void AddPath(const Twine &Path, IncludeDirGroup Group, bool isFramework);
59 
60   /// AddUnmappedPath - Add the specified path to the specified group list,
61   /// without performing any sysroot remapping.
62   void AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
63                        bool isFramework);
64 
65   /// AddSystemHeaderPrefix - Add the specified prefix to the system header
66   /// prefix list.
67   void AddSystemHeaderPrefix(StringRef Prefix, bool IsSystemHeader) {
68     SystemHeaderPrefixes.push_back(std::make_pair(Prefix, IsSystemHeader));
69   }
70 
71   /// AddGnuCPlusPlusIncludePaths - Add the necessary paths to support a gnu
72   ///  libstdc++.
73   void AddGnuCPlusPlusIncludePaths(StringRef Base,
74                                    StringRef ArchDir,
75                                    StringRef Dir32,
76                                    StringRef Dir64,
77                                    const llvm::Triple &triple);
78 
79   /// AddMinGWCPlusPlusIncludePaths - Add the necessary paths to support a MinGW
80   ///  libstdc++.
81   void AddMinGWCPlusPlusIncludePaths(StringRef Base,
82                                      StringRef Arch,
83                                      StringRef Version);
84 
85   /// AddMinGW64CXXPaths - Add the necessary paths to support
86   /// libstdc++ of x86_64-w64-mingw32 aka mingw-w64.
87   void AddMinGW64CXXPaths(StringRef Base,
88                           StringRef Version);
89 
90   // AddDefaultCIncludePaths - Add paths that should always be searched.
91   void AddDefaultCIncludePaths(const llvm::Triple &triple,
92                                const HeaderSearchOptions &HSOpts);
93 
94   // AddDefaultCPlusPlusIncludePaths -  Add paths that should be searched when
95   //  compiling c++.
96   void AddDefaultCPlusPlusIncludePaths(const llvm::Triple &triple,
97                                        const HeaderSearchOptions &HSOpts);
98 
99   /// AddDefaultSystemIncludePaths - Adds the default system include paths so
100   ///  that e.g. stdio.h is found.
101   void AddDefaultIncludePaths(const LangOptions &Lang,
102                               const llvm::Triple &triple,
103                               const HeaderSearchOptions &HSOpts);
104 
105   /// Realize - Merges all search path lists into one list and send it to
106   /// HeaderSearch.
107   void Realize(const LangOptions &Lang);
108 };
109 
110 }  // end anonymous namespace.
111 
112 static bool CanPrefixSysroot(StringRef Path) {
113 #if defined(LLVM_ON_WIN32)
114   return !Path.empty() && llvm::sys::path::is_separator(Path[0]);
115 #else
116   return llvm::sys::path::is_absolute(Path);
117 #endif
118 }
119 
120 void InitHeaderSearch::AddPath(const Twine &Path, IncludeDirGroup Group,
121                                bool isFramework) {
122   // Add the path with sysroot prepended, if desired and this is a system header
123   // group.
124   if (HasSysroot) {
125     SmallString<256> MappedPathStorage;
126     StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
127     if (CanPrefixSysroot(MappedPathStr)) {
128       AddUnmappedPath(IncludeSysroot + Path, Group, isFramework);
129       return;
130     }
131   }
132 
133   AddUnmappedPath(Path, Group, isFramework);
134 }
135 
136 void InitHeaderSearch::AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
137                                        bool isFramework) {
138   assert(!Path.isTriviallyEmpty() && "can't handle empty path here");
139 
140   FileManager &FM = Headers.getFileMgr();
141   SmallString<256> MappedPathStorage;
142   StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
143 
144   // Compute the DirectoryLookup type.
145   SrcMgr::CharacteristicKind Type;
146   if (Group == Quoted || Group == Angled || Group == IndexHeaderMap) {
147     Type = SrcMgr::C_User;
148   } else if (Group == ExternCSystem) {
149     Type = SrcMgr::C_ExternCSystem;
150   } else {
151     Type = SrcMgr::C_System;
152   }
153 
154   // If the directory exists, add it.
155   if (const DirectoryEntry *DE = FM.getDirectory(MappedPathStr)) {
156     IncludePath.push_back(
157       std::make_pair(Group, DirectoryLookup(DE, Type, isFramework)));
158     return;
159   }
160 
161   // Check to see if this is an apple-style headermap (which are not allowed to
162   // be frameworks).
163   if (!isFramework) {
164     if (const FileEntry *FE = FM.getFile(MappedPathStr)) {
165       if (const HeaderMap *HM = Headers.CreateHeaderMap(FE)) {
166         // It is a headermap, add it to the search path.
167         IncludePath.push_back(
168           std::make_pair(Group,
169                          DirectoryLookup(HM, Type, Group == IndexHeaderMap)));
170         return;
171       }
172     }
173   }
174 
175   if (Verbose)
176     llvm::errs() << "ignoring nonexistent directory \""
177                  << MappedPathStr << "\"\n";
178 }
179 
180 void InitHeaderSearch::AddGnuCPlusPlusIncludePaths(StringRef Base,
181                                                    StringRef ArchDir,
182                                                    StringRef Dir32,
183                                                    StringRef Dir64,
184                                                    const llvm::Triple &triple) {
185   // Add the base dir
186   AddPath(Base, CXXSystem, false);
187 
188   // Add the multilib dirs
189   llvm::Triple::ArchType arch = triple.getArch();
190   bool is64bit = arch == llvm::Triple::ppc64 || arch == llvm::Triple::x86_64;
191   if (is64bit)
192     AddPath(Base + "/" + ArchDir + "/" + Dir64, CXXSystem, false);
193   else
194     AddPath(Base + "/" + ArchDir + "/" + Dir32, CXXSystem, false);
195 
196   // Add the backward dir
197   AddPath(Base + "/backward", CXXSystem, false);
198 }
199 
200 void InitHeaderSearch::AddMinGWCPlusPlusIncludePaths(StringRef Base,
201                                                      StringRef Arch,
202                                                      StringRef Version) {
203   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++",
204           CXXSystem, false);
205   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/" + Arch,
206           CXXSystem, false);
207   AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/backward",
208           CXXSystem, false);
209 }
210 
211 void InitHeaderSearch::AddMinGW64CXXPaths(StringRef Base,
212                                           StringRef Version) {
213   // Assumes Base is HeaderSearchOpts' ResourceDir
214   AddPath(Base + "/../../../include/c++/" + Version,
215           CXXSystem, false);
216   AddPath(Base + "/../../../include/c++/" + Version + "/x86_64-w64-mingw32",
217           CXXSystem, false);
218   AddPath(Base + "/../../../include/c++/" + Version + "/i686-w64-mingw32",
219           CXXSystem, false);
220   AddPath(Base + "/../../../include/c++/" + Version + "/backward",
221           CXXSystem, false);
222 }
223 
224 void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
225                                             const HeaderSearchOptions &HSOpts) {
226   llvm::Triple::OSType os = triple.getOS();
227 
228   if (HSOpts.UseStandardSystemIncludes) {
229     switch (os) {
230     case llvm::Triple::FreeBSD:
231     case llvm::Triple::NetBSD:
232     case llvm::Triple::OpenBSD:
233     case llvm::Triple::Bitrig:
234       break;
235     default:
236       // FIXME: temporary hack: hard-coded paths.
237       AddPath("/usr/local/include", System, false);
238       break;
239     }
240   }
241 
242   // Builtin includes use #include_next directives and should be positioned
243   // just prior C include dirs.
244   if (HSOpts.UseBuiltinIncludes) {
245     // Ignore the sys root, we *always* look for clang headers relative to
246     // supplied path.
247     SmallString<128> P = StringRef(HSOpts.ResourceDir);
248     llvm::sys::path::append(P, "include");
249     AddUnmappedPath(P.str(), ExternCSystem, false);
250   }
251 
252   // All remaining additions are for system include directories, early exit if
253   // we aren't using them.
254   if (!HSOpts.UseStandardSystemIncludes)
255     return;
256 
257   // Add dirs specified via 'configure --with-c-include-dirs'.
258   StringRef CIncludeDirs(C_INCLUDE_DIRS);
259   if (CIncludeDirs != "") {
260     SmallVector<StringRef, 5> dirs;
261     CIncludeDirs.split(dirs, ":");
262     for (SmallVectorImpl<StringRef>::iterator i = dirs.begin();
263          i != dirs.end();
264          ++i)
265       AddPath(*i, ExternCSystem, false);
266     return;
267   }
268 
269   switch (os) {
270   case llvm::Triple::Linux:
271     llvm_unreachable("Include management is handled in the driver.");
272 
273   case llvm::Triple::Haiku:
274     AddPath("/boot/common/include", System, false);
275     AddPath("/boot/develop/headers/os", System, false);
276     AddPath("/boot/develop/headers/os/app", System, false);
277     AddPath("/boot/develop/headers/os/arch", System, false);
278     AddPath("/boot/develop/headers/os/device", System, false);
279     AddPath("/boot/develop/headers/os/drivers", System, false);
280     AddPath("/boot/develop/headers/os/game", System, false);
281     AddPath("/boot/develop/headers/os/interface", System, false);
282     AddPath("/boot/develop/headers/os/kernel", System, false);
283     AddPath("/boot/develop/headers/os/locale", System, false);
284     AddPath("/boot/develop/headers/os/mail", System, false);
285     AddPath("/boot/develop/headers/os/media", System, false);
286     AddPath("/boot/develop/headers/os/midi", System, false);
287     AddPath("/boot/develop/headers/os/midi2", System, false);
288     AddPath("/boot/develop/headers/os/net", System, false);
289     AddPath("/boot/develop/headers/os/storage", System, false);
290     AddPath("/boot/develop/headers/os/support", System, false);
291     AddPath("/boot/develop/headers/os/translation", System, false);
292     AddPath("/boot/develop/headers/os/add-ons/graphics", System, false);
293     AddPath("/boot/develop/headers/os/add-ons/input_server", System, false);
294     AddPath("/boot/develop/headers/os/add-ons/screen_saver", System, false);
295     AddPath("/boot/develop/headers/os/add-ons/tracker", System, false);
296     AddPath("/boot/develop/headers/os/be_apps/Deskbar", System, false);
297     AddPath("/boot/develop/headers/os/be_apps/NetPositive", System, false);
298     AddPath("/boot/develop/headers/os/be_apps/Tracker", System, false);
299     AddPath("/boot/develop/headers/cpp", System, false);
300     AddPath("/boot/develop/headers/cpp/i586-pc-haiku", System, false);
301     AddPath("/boot/develop/headers/3rdparty", System, false);
302     AddPath("/boot/develop/headers/bsd", System, false);
303     AddPath("/boot/develop/headers/glibc", System, false);
304     AddPath("/boot/develop/headers/posix", System, false);
305     AddPath("/boot/develop/headers",  System, false);
306     break;
307   case llvm::Triple::RTEMS:
308     break;
309   case llvm::Triple::Win32:
310     switch (triple.getEnvironment()) {
311     default: llvm_unreachable("Include management is handled in the driver.");
312     case llvm::Triple::Cygnus:
313       AddPath("/usr/include/w32api", System, false);
314       break;
315     case llvm::Triple::GNU:
316       // mingw-w64 crt include paths
317       // <sysroot>/i686-w64-mingw32/include
318       SmallString<128> P = StringRef(HSOpts.ResourceDir);
319       llvm::sys::path::append(P, "../../../i686-w64-mingw32/include");
320       AddPath(P.str(), System, false);
321 
322       // <sysroot>/x86_64-w64-mingw32/include
323       P.resize(HSOpts.ResourceDir.size());
324       llvm::sys::path::append(P, "../../../x86_64-w64-mingw32/include");
325       AddPath(P.str(), System, false);
326 
327       // mingw.org crt include paths
328       // <sysroot>/include
329       P.resize(HSOpts.ResourceDir.size());
330       llvm::sys::path::append(P, "../../../include");
331       AddPath(P.str(), System, false);
332       AddPath("/mingw/include", System, false);
333 #if defined(LLVM_ON_WIN32)
334       AddPath("c:/mingw/include", System, false);
335 #endif
336       break;
337     }
338     break;
339   default:
340     break;
341   }
342 
343   if ( os != llvm::Triple::RTEMS )
344     AddPath("/usr/include", ExternCSystem, false);
345 }
346 
347 void InitHeaderSearch::
348 AddDefaultCPlusPlusIncludePaths(const llvm::Triple &triple, const HeaderSearchOptions &HSOpts) {
349   llvm::Triple::OSType os = triple.getOS();
350   // FIXME: temporary hack: hard-coded paths.
351 
352   if (triple.isOSDarwin()) {
353     switch (triple.getArch()) {
354     default: break;
355 
356     case llvm::Triple::ppc:
357     case llvm::Triple::ppc64:
358       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
359                                   "powerpc-apple-darwin10", "", "ppc64",
360                                   triple);
361       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.0.0",
362                                   "powerpc-apple-darwin10", "", "ppc64",
363                                   triple);
364       break;
365 
366     case llvm::Triple::x86:
367     case llvm::Triple::x86_64:
368       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
369                                   "i686-apple-darwin10", "", "x86_64", triple);
370       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.0.0",
371                                   "i686-apple-darwin8", "", "", triple);
372       break;
373 
374     case llvm::Triple::arm:
375     case llvm::Triple::thumb:
376       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
377                                   "arm-apple-darwin10", "v7", "", triple);
378       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
379                                   "arm-apple-darwin10", "v6", "", triple);
380       break;
381 
382     case llvm::Triple::aarch64:
383       AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.2.1",
384                                   "arm64-apple-darwin10", "", "", triple);
385       break;
386     }
387     return;
388   }
389 
390   switch (os) {
391   case llvm::Triple::Linux:
392     llvm_unreachable("Include management is handled in the driver.");
393     break;
394   case llvm::Triple::Win32:
395     switch (triple.getEnvironment()) {
396     default: llvm_unreachable("Include management is handled in the driver.");
397     case llvm::Triple::Cygnus:
398       // Cygwin-1.7
399       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.7.3");
400       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.5.3");
401       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.4");
402       // g++-4 / Cygwin-1.5
403       AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
404       break;
405     case llvm::Triple::GNU:
406       // mingw-w64 C++ include paths (i686-w64-mingw32 and x86_64-w64-mingw32)
407       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.7.0");
408       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.7.1");
409       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.7.2");
410       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.7.3");
411       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.8.0");
412       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.8.1");
413       AddMinGW64CXXPaths(HSOpts.ResourceDir, "4.8.2");
414       // mingw.org C++ include paths
415 #if defined(LLVM_ON_WIN32)
416       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.7.0");
417       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.7.1");
418       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.7.2");
419       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.7.3");
420       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.8.0");
421       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.8.1");
422       AddMinGWCPlusPlusIncludePaths("c:/MinGW/lib/gcc", "mingw32", "4.8.2");
423 #endif
424       break;
425     }
426   case llvm::Triple::DragonFly:
427     if (llvm::sys::fs::exists("/usr/lib/gcc47"))
428       AddPath("/usr/include/c++/4.7", CXXSystem, false);
429     else
430       AddPath("/usr/include/c++/4.4", CXXSystem, false);
431     break;
432   case llvm::Triple::OpenBSD: {
433     std::string t = triple.getTriple();
434     if (t.substr(0, 6) == "x86_64")
435       t.replace(0, 6, "amd64");
436     AddGnuCPlusPlusIncludePaths("/usr/include/g++",
437                                 t, "", "", triple);
438     break;
439   }
440   case llvm::Triple::Minix:
441     AddGnuCPlusPlusIncludePaths("/usr/gnu/include/c++/4.4.3",
442                                 "", "", "", triple);
443     break;
444   case llvm::Triple::Solaris:
445     AddGnuCPlusPlusIncludePaths("/usr/gcc/4.5/include/c++/4.5.2/",
446                                 "i386-pc-solaris2.11", "", "", triple);
447     break;
448   default:
449     break;
450   }
451 }
452 
453 void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
454                                               const llvm::Triple &triple,
455                                             const HeaderSearchOptions &HSOpts) {
456   // NB: This code path is going away. All of the logic is moving into the
457   // driver which has the information necessary to do target-specific
458   // selections of default include paths. Each target which moves there will be
459   // exempted from this logic here until we can delete the entire pile of code.
460   switch (triple.getOS()) {
461   default:
462     break; // Everything else continues to use this routine's logic.
463 
464   case llvm::Triple::Linux:
465     return;
466 
467   case llvm::Triple::Win32:
468     if (triple.getEnvironment() == llvm::Triple::MSVC ||
469         triple.getEnvironment() == llvm::Triple::Itanium ||
470         triple.isOSBinFormatMachO())
471       return;
472     break;
473   }
474 
475   if (Lang.CPlusPlus && HSOpts.UseStandardCXXIncludes &&
476       HSOpts.UseStandardSystemIncludes) {
477     if (HSOpts.UseLibcxx) {
478       if (triple.isOSDarwin()) {
479         // On Darwin, libc++ may be installed alongside the compiler in
480         // include/c++/v1.
481         if (!HSOpts.ResourceDir.empty()) {
482           // Remove version from foo/lib/clang/version
483           StringRef NoVer = llvm::sys::path::parent_path(HSOpts.ResourceDir);
484           // Remove clang from foo/lib/clang
485           StringRef Lib = llvm::sys::path::parent_path(NoVer);
486           // Remove lib from foo/lib
487           SmallString<128> P = llvm::sys::path::parent_path(Lib);
488 
489           // Get foo/include/c++/v1
490           llvm::sys::path::append(P, "include", "c++", "v1");
491           AddUnmappedPath(P.str(), CXXSystem, false);
492         }
493       }
494       // On Solaris, include the support directory for things like xlocale and
495       // fudged system headers.
496       if (triple.getOS() == llvm::Triple::Solaris)
497         AddPath("/usr/include/c++/v1/support/solaris", CXXSystem, false);
498 
499       AddPath("/usr/include/c++/v1", CXXSystem, false);
500     } else {
501       AddDefaultCPlusPlusIncludePaths(triple, HSOpts);
502     }
503   }
504 
505   AddDefaultCIncludePaths(triple, HSOpts);
506 
507   // Add the default framework include paths on Darwin.
508   if (HSOpts.UseStandardSystemIncludes) {
509     if (triple.isOSDarwin()) {
510       AddPath("/System/Library/Frameworks", System, true);
511       AddPath("/Library/Frameworks", System, true);
512     }
513   }
514 }
515 
516 /// RemoveDuplicates - If there are duplicate directory entries in the specified
517 /// search list, remove the later (dead) ones.  Returns the number of non-system
518 /// headers removed, which is used to update NumAngled.
519 static unsigned RemoveDuplicates(std::vector<DirectoryLookup> &SearchList,
520                                  unsigned First, bool Verbose) {
521   llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenDirs;
522   llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenFrameworkDirs;
523   llvm::SmallPtrSet<const HeaderMap *, 8> SeenHeaderMaps;
524   unsigned NonSystemRemoved = 0;
525   for (unsigned i = First; i != SearchList.size(); ++i) {
526     unsigned DirToRemove = i;
527 
528     const DirectoryLookup &CurEntry = SearchList[i];
529 
530     if (CurEntry.isNormalDir()) {
531       // If this isn't the first time we've seen this dir, remove it.
532       if (SeenDirs.insert(CurEntry.getDir()).second)
533         continue;
534     } else if (CurEntry.isFramework()) {
535       // If this isn't the first time we've seen this framework dir, remove it.
536       if (SeenFrameworkDirs.insert(CurEntry.getFrameworkDir()).second)
537         continue;
538     } else {
539       assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
540       // If this isn't the first time we've seen this headermap, remove it.
541       if (SeenHeaderMaps.insert(CurEntry.getHeaderMap()).second)
542         continue;
543     }
544 
545     // If we have a normal #include dir/framework/headermap that is shadowed
546     // later in the chain by a system include location, we actually want to
547     // ignore the user's request and drop the user dir... keeping the system
548     // dir.  This is weird, but required to emulate GCC's search path correctly.
549     //
550     // Since dupes of system dirs are rare, just rescan to find the original
551     // that we're nuking instead of using a DenseMap.
552     if (CurEntry.getDirCharacteristic() != SrcMgr::C_User) {
553       // Find the dir that this is the same of.
554       unsigned FirstDir;
555       for (FirstDir = 0; ; ++FirstDir) {
556         assert(FirstDir != i && "Didn't find dupe?");
557 
558         const DirectoryLookup &SearchEntry = SearchList[FirstDir];
559 
560         // If these are different lookup types, then they can't be the dupe.
561         if (SearchEntry.getLookupType() != CurEntry.getLookupType())
562           continue;
563 
564         bool isSame;
565         if (CurEntry.isNormalDir())
566           isSame = SearchEntry.getDir() == CurEntry.getDir();
567         else if (CurEntry.isFramework())
568           isSame = SearchEntry.getFrameworkDir() == CurEntry.getFrameworkDir();
569         else {
570           assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
571           isSame = SearchEntry.getHeaderMap() == CurEntry.getHeaderMap();
572         }
573 
574         if (isSame)
575           break;
576       }
577 
578       // If the first dir in the search path is a non-system dir, zap it
579       // instead of the system one.
580       if (SearchList[FirstDir].getDirCharacteristic() == SrcMgr::C_User)
581         DirToRemove = FirstDir;
582     }
583 
584     if (Verbose) {
585       llvm::errs() << "ignoring duplicate directory \""
586                    << CurEntry.getName() << "\"\n";
587       if (DirToRemove != i)
588         llvm::errs() << "  as it is a non-system directory that duplicates "
589                      << "a system directory\n";
590     }
591     if (DirToRemove != i)
592       ++NonSystemRemoved;
593 
594     // This is reached if the current entry is a duplicate.  Remove the
595     // DirToRemove (usually the current dir).
596     SearchList.erase(SearchList.begin()+DirToRemove);
597     --i;
598   }
599   return NonSystemRemoved;
600 }
601 
602 
603 void InitHeaderSearch::Realize(const LangOptions &Lang) {
604   // Concatenate ANGLE+SYSTEM+AFTER chains together into SearchList.
605   std::vector<DirectoryLookup> SearchList;
606   SearchList.reserve(IncludePath.size());
607 
608   // Quoted arguments go first.
609   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
610        it != ie; ++it) {
611     if (it->first == Quoted)
612       SearchList.push_back(it->second);
613   }
614   // Deduplicate and remember index.
615   RemoveDuplicates(SearchList, 0, Verbose);
616   unsigned NumQuoted = SearchList.size();
617 
618   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
619        it != ie; ++it) {
620     if (it->first == Angled || it->first == IndexHeaderMap)
621       SearchList.push_back(it->second);
622   }
623 
624   RemoveDuplicates(SearchList, NumQuoted, Verbose);
625   unsigned NumAngled = SearchList.size();
626 
627   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
628        it != ie; ++it) {
629     if (it->first == System || it->first == ExternCSystem ||
630         (!Lang.ObjC1 && !Lang.CPlusPlus && it->first == CSystem)    ||
631         (/*FIXME !Lang.ObjC1 && */Lang.CPlusPlus  && it->first == CXXSystem)  ||
632         (Lang.ObjC1  && !Lang.CPlusPlus && it->first == ObjCSystem) ||
633         (Lang.ObjC1  && Lang.CPlusPlus  && it->first == ObjCXXSystem))
634       SearchList.push_back(it->second);
635   }
636 
637   for (path_iterator it = IncludePath.begin(), ie = IncludePath.end();
638        it != ie; ++it) {
639     if (it->first == After)
640       SearchList.push_back(it->second);
641   }
642 
643   // Remove duplicates across both the Angled and System directories.  GCC does
644   // this and failing to remove duplicates across these two groups breaks
645   // #include_next.
646   unsigned NonSystemRemoved = RemoveDuplicates(SearchList, NumQuoted, Verbose);
647   NumAngled -= NonSystemRemoved;
648 
649   bool DontSearchCurDir = false;  // TODO: set to true if -I- is set?
650   Headers.SetSearchPaths(SearchList, NumQuoted, NumAngled, DontSearchCurDir);
651 
652   Headers.SetSystemHeaderPrefixes(SystemHeaderPrefixes);
653 
654   // If verbose, print the list of directories that will be searched.
655   if (Verbose) {
656     llvm::errs() << "#include \"...\" search starts here:\n";
657     for (unsigned i = 0, e = SearchList.size(); i != e; ++i) {
658       if (i == NumQuoted)
659         llvm::errs() << "#include <...> search starts here:\n";
660       const char *Name = SearchList[i].getName();
661       const char *Suffix;
662       if (SearchList[i].isNormalDir())
663         Suffix = "";
664       else if (SearchList[i].isFramework())
665         Suffix = " (framework directory)";
666       else {
667         assert(SearchList[i].isHeaderMap() && "Unknown DirectoryLookup");
668         Suffix = " (headermap)";
669       }
670       llvm::errs() << " " << Name << Suffix << "\n";
671     }
672     llvm::errs() << "End of search list.\n";
673   }
674 }
675 
676 void clang::ApplyHeaderSearchOptions(HeaderSearch &HS,
677                                      const HeaderSearchOptions &HSOpts,
678                                      const LangOptions &Lang,
679                                      const llvm::Triple &Triple) {
680   InitHeaderSearch Init(HS, HSOpts.Verbose, HSOpts.Sysroot);
681 
682   // Add the user defined entries.
683   for (unsigned i = 0, e = HSOpts.UserEntries.size(); i != e; ++i) {
684     const HeaderSearchOptions::Entry &E = HSOpts.UserEntries[i];
685     if (E.IgnoreSysRoot) {
686       Init.AddUnmappedPath(E.Path, E.Group, E.IsFramework);
687     } else {
688       Init.AddPath(E.Path, E.Group, E.IsFramework);
689     }
690   }
691 
692   Init.AddDefaultIncludePaths(Lang, Triple, HSOpts);
693 
694   for (unsigned i = 0, e = HSOpts.SystemHeaderPrefixes.size(); i != e; ++i)
695     Init.AddSystemHeaderPrefix(HSOpts.SystemHeaderPrefixes[i].Prefix,
696                                HSOpts.SystemHeaderPrefixes[i].IsSystemHeader);
697 
698   if (HSOpts.UseBuiltinIncludes) {
699     // Set up the builtin include directory in the module map.
700     SmallString<128> P = StringRef(HSOpts.ResourceDir);
701     llvm::sys::path::append(P, "include");
702     if (const DirectoryEntry *Dir = HS.getFileMgr().getDirectory(P.str()))
703       HS.getModuleMap().setBuiltinIncludeDir(Dir);
704   }
705 
706   Init.Realize(Lang);
707 }
708