[Preprocessor] Add a note with framework location for "file not found" error.

When a framework with the same name is available at multiple framework
search paths, we use the first matching location. If a framework at this
location doesn't have all the headers, it can be confusing for
developers because they see only an error `'Foo/Foo.h' file not found`,
can find the complete framework with required header, and don't know the
incomplete framework was used instead.

Add a note explaining a framework without required header was found.
Also mention framework directory path to make it easier to find the
incomplete framework.

rdar://problem/39246514

Reviewers: arphaman, erik.pilkington, jkorous

Reviewed By: jkorous

Subscribers: jkorous, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D56561

llvm-svn: 353231
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
index 9b90512..a71d74e 100644
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -286,7 +286,7 @@
     const DirectoryLookup *CurDir = nullptr;
     const FileEntry *FE = HS.LookupFile(
         Name, SourceLocation(), /*Angled*/ false, nullptr, CurDir,
-        None, nullptr, nullptr, nullptr, nullptr, nullptr);
+        None, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr);
     if (!FE) {
       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
         << Name;
diff --git a/clang/lib/Frontend/Rewrite/InclusionRewriter.cpp b/clang/lib/Frontend/Rewrite/InclusionRewriter.cpp
index 4797a64..cb4e773 100644
--- a/clang/lib/Frontend/Rewrite/InclusionRewriter.cpp
+++ b/clang/lib/Frontend/Rewrite/InclusionRewriter.cpp
@@ -414,7 +414,7 @@
   // FIXME: Why don't we call PP.LookupFile here?
   const FileEntry *File = PP.getHeaderSearchInfo().LookupFile(
       Filename, SourceLocation(), isAngled, Lookup, CurDir, Includers, nullptr,
-      nullptr, nullptr, nullptr, nullptr);
+      nullptr, nullptr, nullptr, nullptr, nullptr);
 
   FileExists = File != nullptr;
   return true;
diff --git a/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp b/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp
index 33cb148..95f847c 100644
--- a/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp
+++ b/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp
@@ -480,7 +480,7 @@
         const DirectoryLookup *CurDir;
         const FileEntry *FE =
             PP->LookupFile(Pos, Filename, false, nullptr, nullptr, CurDir,
-                           nullptr, nullptr, nullptr, nullptr);
+                           nullptr, nullptr, nullptr, nullptr, nullptr);
         if (!FE) {
           Diags.Report(Pos.getLocWithOffset(PH.C-PH.Begin),
                        diag::err_verify_missing_file) << Filename << KindStr;
diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index 32393d1..9c92f77 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -334,6 +334,7 @@
     Module *RequestingModule,
     ModuleMap::KnownHeader *SuggestedModule,
     bool &InUserSpecifiedSystemFramework,
+    bool &IsFrameworkFound,
     bool &HasBeenMapped,
     SmallVectorImpl<char> &MappedName) const {
   InUserSpecifiedSystemFramework = false;
@@ -362,7 +363,7 @@
   if (isFramework())
     return DoFrameworkLookup(Filename, HS, SearchPath, RelativePath,
                              RequestingModule, SuggestedModule,
-                             InUserSpecifiedSystemFramework);
+                             InUserSpecifiedSystemFramework, IsFrameworkFound);
 
   assert(isHeaderMap() && "Unknown directory lookup");
   const HeaderMap *HM = getHeaderMap();
@@ -462,7 +463,7 @@
     StringRef Filename, HeaderSearch &HS, SmallVectorImpl<char> *SearchPath,
     SmallVectorImpl<char> *RelativePath, Module *RequestingModule,
     ModuleMap::KnownHeader *SuggestedModule,
-    bool &InUserSpecifiedSystemFramework) const {
+    bool &InUserSpecifiedSystemFramework, bool &IsFrameworkFound) const {
   FileManager &FileMgr = HS.getFileMgr();
 
   // Framework names must have a '/' in the filename.
@@ -471,7 +472,7 @@
 
   // Find out if this is the home for the specified framework, by checking
   // HeaderSearch.  Possible answers are yes/no and unknown.
-  HeaderSearch::FrameworkCacheEntry &CacheEntry =
+  FrameworkCacheEntry &CacheEntry =
     HS.LookupFrameworkCache(Filename.substr(0, SlashPos));
 
   // If it is known and in some other directory, fail.
@@ -516,8 +517,9 @@
     }
   }
 
-  // Set the 'user-specified system framework' flag.
+  // Set out flags.
   InUserSpecifiedSystemFramework = CacheEntry.IsUserSpecifiedSystemFramework;
+  IsFrameworkFound = CacheEntry.Directory;
 
   if (RelativePath) {
     RelativePath->clear();
@@ -696,10 +698,14 @@
     ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers,
     SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
     Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
-    bool *IsMapped, bool SkipCache, bool BuildSystemModule) {
+    bool *IsMapped, bool *IsFrameworkFound, bool SkipCache,
+    bool BuildSystemModule) {
   if (IsMapped)
     *IsMapped = false;
 
+  if (IsFrameworkFound)
+    *IsFrameworkFound = false;
+
   if (SuggestedModule)
     *SuggestedModule = ModuleMap::KnownHeader();
 
@@ -851,16 +857,19 @@
   for (; i != SearchDirs.size(); ++i) {
     bool InUserSpecifiedSystemFramework = false;
     bool HasBeenMapped = false;
+    bool IsFrameworkFoundInDir = false;
     const FileEntry *FE = SearchDirs[i].LookupFile(
         Filename, *this, IncludeLoc, SearchPath, RelativePath, RequestingModule,
-        SuggestedModule, InUserSpecifiedSystemFramework, HasBeenMapped,
-        MappedName);
+        SuggestedModule, InUserSpecifiedSystemFramework, IsFrameworkFoundInDir,
+        HasBeenMapped, MappedName);
     if (HasBeenMapped) {
       CacheLookup.MappedName =
           copyString(Filename, LookupFileCache.getAllocator());
       if (IsMapped)
         *IsMapped = true;
     }
+    if (IsFrameworkFound)
+      *IsFrameworkFound |= IsFrameworkFoundInDir;
     if (!FE) continue;
 
     CurDir = &SearchDirs[i];
@@ -926,10 +935,10 @@
       ScratchFilename += '/';
       ScratchFilename += Filename;
 
-      const FileEntry *FE =
-          LookupFile(ScratchFilename, IncludeLoc, /*isAngled=*/true, FromDir,
-                     CurDir, Includers.front(), SearchPath, RelativePath,
-                     RequestingModule, SuggestedModule, IsMapped);
+      const FileEntry *FE = LookupFile(
+          ScratchFilename, IncludeLoc, /*isAngled=*/true, FromDir, CurDir,
+          Includers.front(), SearchPath, RelativePath, RequestingModule,
+          SuggestedModule, IsMapped, /*IsFrameworkFound=*/nullptr);
 
       if (checkMSVCHeaderSearch(Diags, MSFE, FE, IncludeLoc)) {
         if (SuggestedModule)
diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index d4fad6a..5e97d9f 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -665,7 +665,8 @@
     const DirectoryLookup *FromDir, const FileEntry *FromFile,
     const DirectoryLookup *&CurDir, SmallVectorImpl<char> *SearchPath,
     SmallVectorImpl<char> *RelativePath,
-    ModuleMap::KnownHeader *SuggestedModule, bool *IsMapped, bool SkipCache) {
+    ModuleMap::KnownHeader *SuggestedModule, bool *IsMapped,
+    bool *IsFrameworkFound, bool SkipCache) {
   Module *RequestingModule = getModuleForLocation(FilenameLoc);
   bool RequestingModuleIsModuleInterface = !SourceMgr.isInMainFile(FilenameLoc);
 
@@ -723,7 +724,8 @@
     while (const FileEntry *FE = HeaderInfo.LookupFile(
                Filename, FilenameLoc, isAngled, TmpFromDir, TmpCurDir,
                Includers, SearchPath, RelativePath, RequestingModule,
-               SuggestedModule, /*IsMapped=*/nullptr, SkipCache)) {
+               SuggestedModule, /*IsMapped=*/nullptr,
+               /*IsFrameworkFound=*/nullptr, SkipCache)) {
       // Keep looking as if this file did a #include_next.
       TmpFromDir = TmpCurDir;
       ++TmpFromDir;
@@ -739,8 +741,8 @@
   // Do a standard file entry lookup.
   const FileEntry *FE = HeaderInfo.LookupFile(
       Filename, FilenameLoc, isAngled, FromDir, CurDir, Includers, SearchPath,
-      RelativePath, RequestingModule, SuggestedModule, IsMapped, SkipCache,
-      BuildSystemModule);
+      RelativePath, RequestingModule, SuggestedModule, IsMapped,
+      IsFrameworkFound, SkipCache, BuildSystemModule);
   if (FE) {
     if (SuggestedModule && !LangOpts.AsmPreprocessor)
       HeaderInfo.getModuleMap().diagnoseHeaderInclusion(
@@ -1756,6 +1758,7 @@
 
   // Search include directories.
   bool IsMapped = false;
+  bool IsFrameworkFound = false;
   const DirectoryLookup *CurDir;
   SmallString<1024> SearchPath;
   SmallString<1024> RelativePath;
@@ -1774,7 +1777,7 @@
       FilenameLoc, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename,
       isAngled, LookupFrom, LookupFromFile, CurDir,
       Callbacks ? &SearchPath : nullptr, Callbacks ? &RelativePath : nullptr,
-      &SuggestedModule, &IsMapped);
+      &SuggestedModule, &IsMapped, &IsFrameworkFound);
 
   if (!File) {
     if (Callbacks) {
@@ -1791,7 +1794,8 @@
               FilenameLoc,
               LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled,
               LookupFrom, LookupFromFile, CurDir, nullptr, nullptr,
-              &SuggestedModule, &IsMapped, /*SkipCache*/ true);
+              &SuggestedModule, &IsMapped, /*IsFrameworkFound=*/nullptr,
+              /*SkipCache*/ true);
         }
       }
     }
@@ -1806,7 +1810,8 @@
             LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, false,
             LookupFrom, LookupFromFile, CurDir,
             Callbacks ? &SearchPath : nullptr,
-            Callbacks ? &RelativePath : nullptr, &SuggestedModule, &IsMapped);
+            Callbacks ? &RelativePath : nullptr, &SuggestedModule, &IsMapped,
+            /*IsFrameworkFound=*/nullptr);
         if (File) {
           SourceRange Range(FilenameTok.getLocation(), CharEnd);
           Diag(FilenameTok, diag::err_pp_file_not_found_angled_include_not_fatal) <<
@@ -1842,7 +1847,8 @@
                                 : TypoCorrectionName,
             isAngled, LookupFrom, LookupFromFile, CurDir,
             Callbacks ? &SearchPath : nullptr,
-            Callbacks ? &RelativePath : nullptr, &SuggestedModule, &IsMapped);
+            Callbacks ? &RelativePath : nullptr, &SuggestedModule, &IsMapped,
+            /*IsFrameworkFound=*/nullptr);
         if (File) {
           SourceRange Range(FilenameTok.getLocation(), CharEnd);
           auto Hint = isAngled
@@ -1859,9 +1865,22 @@
       }
 
       // If the file is still not found, just go with the vanilla diagnostic
-      if (!File)
+      if (!File) {
         Diag(FilenameTok, diag::err_pp_file_not_found) << OriginalFilename
                                                        << FilenameRange;
+        if (IsFrameworkFound) {
+          size_t SlashPos = OriginalFilename.find('/');
+          assert(SlashPos != StringRef::npos &&
+                 "Include with framework name should have '/' in the filename");
+          StringRef FrameworkName = OriginalFilename.substr(0, SlashPos);
+          FrameworkCacheEntry &CacheEntry =
+              HeaderInfo.LookupFrameworkCache(FrameworkName);
+          assert(CacheEntry.Directory && "Found framework should be in cache");
+          Diag(FilenameTok, diag::note_pp_framework_without_header)
+              << OriginalFilename.substr(SlashPos + 1) << FrameworkName
+              << CacheEntry.Directory->getName();
+        }
+      }
     }
   }
 
diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index 00bc7aa..2e9c686 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -1235,7 +1235,7 @@
   const DirectoryLookup *CurDir;
   const FileEntry *File =
       PP.LookupFile(FilenameLoc, Filename, isAngled, LookupFrom, LookupFromFile,
-                    CurDir, nullptr, nullptr, nullptr, nullptr);
+                    CurDir, nullptr, nullptr, nullptr, nullptr, nullptr);
 
   if (PPCallbacks *Callbacks = PP.getPPCallbacks()) {
     SrcMgr::CharacteristicKind FileType = SrcMgr::C_User;
diff --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index 41d170e..c82b531 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -506,7 +506,7 @@
   const DirectoryLookup *CurDir;
   const FileEntry *File =
       LookupFile(FilenameTok.getLocation(), Filename, isAngled, nullptr,
-                 nullptr, CurDir, nullptr, nullptr, nullptr, nullptr);
+                 nullptr, CurDir, nullptr, nullptr, nullptr, nullptr, nullptr);
   if (!File) {
     if (!SuppressIncludeNotFoundError)
       Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 2952c64..9519314 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -566,7 +566,8 @@
         SourceLocation(), PPOpts->PCHThroughHeader,
         /*isAngled=*/false, /*FromDir=*/nullptr, /*FromFile=*/nullptr, CurDir,
         /*SearchPath=*/nullptr, /*RelativePath=*/nullptr,
-        /*SuggestedModule=*/nullptr, /*IsMapped=*/nullptr);
+        /*SuggestedModule=*/nullptr, /*IsMapped=*/nullptr,
+        /*IsFrameworkFound=*/nullptr);
     if (!File) {
       Diag(SourceLocation(), diag::err_pp_through_header_not_found)
           << PPOpts->PCHThroughHeader;