Index: clang-tools-extra/clang-doc/BitcodeReader.cpp
===================================================================
--- clang-tools-extra/clang-doc/BitcodeReader.cpp
+++ clang-tools-extra/clang-doc/BitcodeReader.cpp
@@ -83,7 +83,7 @@
   if (R[0] > INT_MAX)
     return llvm::make_error<llvm::StringError>("Integer too large to parse.\n",
                                                llvm::inconvertibleErrorCode());
-  Field.emplace((int)R[0], Blob);
+  Field.emplace((int)R[0], Blob, (bool)R[1]);
   return llvm::Error::success();
 }
 
@@ -129,7 +129,7 @@
   if (R[0] > INT_MAX)
     return llvm::make_error<llvm::StringError>("Integer too large to parse.\n",
                                                llvm::inconvertibleErrorCode());
-  Field.emplace_back((int)R[0], Blob);
+  Field.emplace_back((int)R[0], Blob, (bool)R[1]);
   return llvm::Error::success();
 }
 
Index: clang-tools-extra/clang-doc/BitcodeWriter.cpp
===================================================================
--- clang-tools-extra/clang-doc/BitcodeWriter.cpp
+++ clang-tools-extra/clang-doc/BitcodeWriter.cpp
@@ -77,10 +77,13 @@
       {// 0. Fixed-size integer (line number)
        llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Fixed,
                              BitCodeConstants::LineNumberSize),
-       // 1. Fixed-size integer (length of the following string (filename))
+       // 1. Boolean (IsFileInRootDir)
+       llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Fixed,
+                             BitCodeConstants::BoolSize),
+       // 2. Fixed-size integer (length of the following string (filename))
        llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Fixed,
                              BitCodeConstants::StringLengthSize),
-       // 2. The string blob
+       // 3. The string blob
        llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob)});
 }
 
@@ -314,6 +317,7 @@
   // FIXME: Assert that the line number is of the appropriate size.
   Record.push_back(Loc.LineNumber);
   assert(Loc.Filename.size() < (1U << BitCodeConstants::StringLengthSize));
+  Record.push_back(Loc.IsFileInRootDir);
   Record.push_back(Loc.Filename.size());
   Stream.EmitRecordWithBlob(Abbrevs.get(ID), Record, Loc.Filename);
 }
Index: clang-tools-extra/clang-doc/HTMLGenerator.cpp
===================================================================
--- clang-tools-extra/clang-doc/HTMLGenerator.cpp
+++ clang-tools-extra/clang-doc/HTMLGenerator.cpp
@@ -269,12 +269,15 @@
   return Out;
 }
 
-static std::vector<std::unique_ptr<TagNode>> genHTML(const EnumInfo &I);
-static std::vector<std::unique_ptr<TagNode>> genHTML(const FunctionInfo &I,
-                                                     StringRef ParentInfoDir);
+static std::vector<std::unique_ptr<TagNode>>
+genHTML(const EnumInfo &I, const ClangDocContext &CDCtx);
+static std::vector<std::unique_ptr<TagNode>>
+genHTML(const FunctionInfo &I, const ClangDocContext &CDCtx,
+        StringRef ParentInfoDir);
 
 static std::vector<std::unique_ptr<TagNode>>
-genEnumsBlock(const std::vector<EnumInfo> &Enums) {
+genEnumsBlock(const std::vector<EnumInfo> &Enums,
+              const ClangDocContext &CDCtx) {
   if (Enums.empty())
     return {};
 
@@ -283,7 +286,7 @@
   Out.emplace_back(llvm::make_unique<TagNode>(HTMLTag::TAG_DIV));
   auto &DivBody = Out.back();
   for (const auto &E : Enums) {
-    std::vector<std::unique_ptr<TagNode>> Nodes = genHTML(E);
+    std::vector<std::unique_ptr<TagNode>> Nodes = genHTML(E, CDCtx);
     AppendVector(std::move(Nodes), DivBody->Children);
   }
   return Out;
@@ -302,7 +305,7 @@
 
 static std::vector<std::unique_ptr<TagNode>>
 genFunctionsBlock(const std::vector<FunctionInfo> &Functions,
-                  StringRef ParentInfoDir) {
+                  const ClangDocContext &CDCtx, StringRef ParentInfoDir) {
   if (Functions.empty())
     return {};
 
@@ -311,7 +314,8 @@
   Out.emplace_back(llvm::make_unique<TagNode>(HTMLTag::TAG_DIV));
   auto &DivBody = Out.back();
   for (const auto &F : Functions) {
-    std::vector<std::unique_ptr<TagNode>> Nodes = genHTML(F, ParentInfoDir);
+    std::vector<std::unique_ptr<TagNode>> Nodes =
+        genHTML(F, CDCtx, ParentInfoDir);
     AppendVector(std::move(Nodes), DivBody->Children);
   }
   return Out;
@@ -356,10 +360,27 @@
   return Out;
 }
 
-static std::unique_ptr<TagNode> writeFileDefinition(const Location &L) {
-  return llvm::make_unique<TagNode>(
-      HTMLTag::TAG_P,
-      "Defined at line " + std::to_string(L.LineNumber) + " of " + L.Filename);
+static std::unique_ptr<TagNode> writeFileDefinition(const Location &L,
+                                                    StringRef RepositoryUrl) {
+  if (!L.IsFileInRootDir || RepositoryUrl.empty())
+    return llvm::make_unique<TagNode>(
+        HTMLTag::TAG_P, "Defined at line " + std::to_string(L.LineNumber) +
+                            " of file " + L.Filename);
+  SmallString<128> FileURL(RepositoryUrl);
+  llvm::sys::path::append(FileURL, llvm::sys::path::Style::posix, L.Filename);
+  auto Node = llvm::make_unique<TagNode>(HTMLTag::TAG_P);
+  Node->Children.emplace_back(llvm::make_unique<TextNode>("Defined at line "));
+  auto LocNumberNode =
+      llvm::make_unique<TagNode>(HTMLTag::TAG_A, std::to_string(L.LineNumber));
+  LocNumberNode->Attributes.try_emplace(
+      "href", (FileURL + "#" + std::to_string(L.LineNumber)).str());
+  Node->Children.emplace_back(std::move(LocNumberNode));
+  Node->Children.emplace_back(llvm::make_unique<TextNode>(" of file "));
+  auto LocFileNode = llvm::make_unique<TagNode>(
+      HTMLTag::TAG_A, llvm::sys::path::filename(FileURL));
+  LocFileNode->Attributes.try_emplace("href", FileURL);
+  Node->Children.emplace_back(std::move(LocFileNode));
+  return Node;
 }
 
 static std::unique_ptr<HTMLNode> genHTML(const CommentInfo &I) {
@@ -398,7 +419,8 @@
   return CommentBlock;
 }
 
-static std::vector<std::unique_ptr<TagNode>> genHTML(const EnumInfo &I) {
+static std::vector<std::unique_ptr<TagNode>>
+genHTML(const EnumInfo &I, const ClangDocContext &CDCtx) {
   std::vector<std::unique_ptr<TagNode>> Out;
   std::string EnumType;
   if (I.Scoped)
@@ -414,7 +436,8 @@
     Out.emplace_back(std::move(Node));
 
   if (I.DefLoc)
-    Out.emplace_back(writeFileDefinition(I.DefLoc.getValue()));
+    Out.emplace_back(
+        writeFileDefinition(I.DefLoc.getValue(), CDCtx.RepositoryUrl));
 
   std::string Description;
   if (!I.Description.empty())
@@ -423,8 +446,9 @@
   return Out;
 }
 
-static std::vector<std::unique_ptr<TagNode>> genHTML(const FunctionInfo &I,
-                                                     StringRef ParentInfoDir) {
+static std::vector<std::unique_ptr<TagNode>>
+genHTML(const FunctionInfo &I, const ClangDocContext &CDCtx,
+        StringRef ParentInfoDir) {
   std::vector<std::unique_ptr<TagNode>> Out;
   Out.emplace_back(llvm::make_unique<TagNode>(HTMLTag::TAG_H3, I.Name));
 
@@ -454,7 +478,8 @@
   FunctionHeader->Children.emplace_back(llvm::make_unique<TextNode>(")"));
 
   if (I.DefLoc)
-    Out.emplace_back(writeFileDefinition(I.DefLoc.getValue()));
+    Out.emplace_back(
+        writeFileDefinition(I.DefLoc.getValue(), CDCtx.RepositoryUrl));
 
   std::string Description;
   if (!I.Description.empty())
@@ -463,8 +488,9 @@
   return Out;
 }
 
-static std::vector<std::unique_ptr<TagNode>> genHTML(const NamespaceInfo &I,
-                                                     std::string &InfoTitle) {
+static std::vector<std::unique_ptr<TagNode>>
+genHTML(const NamespaceInfo &I, const ClangDocContext &CDCtx,
+        std::string &InfoTitle) {
   std::vector<std::unique_ptr<TagNode>> Out;
   if (I.Name.str() == "")
     InfoTitle = "Global Namespace";
@@ -485,23 +511,25 @@
   AppendVector(std::move(ChildRecords), Out);
 
   std::vector<std::unique_ptr<TagNode>> ChildFunctions =
-      genFunctionsBlock(I.ChildFunctions, I.Path);
+      genFunctionsBlock(I.ChildFunctions, CDCtx, I.Path);
   AppendVector(std::move(ChildFunctions), Out);
   std::vector<std::unique_ptr<TagNode>> ChildEnums =
-      genEnumsBlock(I.ChildEnums);
+      genEnumsBlock(I.ChildEnums, CDCtx);
   AppendVector(std::move(ChildEnums), Out);
 
   return Out;
 }
 
-static std::vector<std::unique_ptr<TagNode>> genHTML(const RecordInfo &I,
-                                                     std::string &InfoTitle) {
+static std::vector<std::unique_ptr<TagNode>>
+genHTML(const RecordInfo &I, const ClangDocContext &CDCtx,
+        std::string &InfoTitle) {
   std::vector<std::unique_ptr<TagNode>> Out;
   InfoTitle = (getTagType(I.TagType) + " " + I.Name).str();
   Out.emplace_back(llvm::make_unique<TagNode>(HTMLTag::TAG_H1, InfoTitle));
 
   if (I.DefLoc)
-    Out.emplace_back(writeFileDefinition(I.DefLoc.getValue()));
+    Out.emplace_back(
+        writeFileDefinition(I.DefLoc.getValue(), CDCtx.RepositoryUrl));
 
   std::string Description;
   if (!I.Description.empty())
@@ -534,10 +562,10 @@
   AppendVector(std::move(ChildRecords), Out);
 
   std::vector<std::unique_ptr<TagNode>> ChildFunctions =
-      genFunctionsBlock(I.ChildFunctions, I.Path);
+      genFunctionsBlock(I.ChildFunctions, CDCtx, I.Path);
   AppendVector(std::move(ChildFunctions), Out);
   std::vector<std::unique_ptr<TagNode>> ChildEnums =
-      genEnumsBlock(I.ChildEnums);
+      genEnumsBlock(I.ChildEnums, CDCtx);
   AppendVector(std::move(ChildEnums), Out);
 
   return Out;
@@ -569,25 +597,25 @@
   switch (I->IT) {
   case InfoType::IT_namespace: {
     std::vector<std::unique_ptr<TagNode>> Nodes =
-        genHTML(*static_cast<clang::doc::NamespaceInfo *>(I), InfoTitle);
+        genHTML(*static_cast<clang::doc::NamespaceInfo *>(I), CDCtx, InfoTitle);
     AppendVector(std::move(Nodes), MainContentNode->Children);
     break;
   }
   case InfoType::IT_record: {
     std::vector<std::unique_ptr<TagNode>> Nodes =
-        genHTML(*static_cast<clang::doc::RecordInfo *>(I), InfoTitle);
+        genHTML(*static_cast<clang::doc::RecordInfo *>(I), CDCtx, InfoTitle);
     AppendVector(std::move(Nodes), MainContentNode->Children);
     break;
   }
   case InfoType::IT_enum: {
     std::vector<std::unique_ptr<TagNode>> Nodes =
-        genHTML(*static_cast<clang::doc::EnumInfo *>(I));
+        genHTML(*static_cast<clang::doc::EnumInfo *>(I), CDCtx);
     AppendVector(std::move(Nodes), MainContentNode->Children);
     break;
   }
   case InfoType::IT_function: {
     std::vector<std::unique_ptr<TagNode>> Nodes =
-        genHTML(*static_cast<clang::doc::FunctionInfo *>(I), "");
+        genHTML(*static_cast<clang::doc::FunctionInfo *>(I), CDCtx, "");
     AppendVector(std::move(Nodes), MainContentNode->Children);
     break;
   }
Index: clang-tools-extra/clang-doc/Mapper.h
===================================================================
--- clang-tools-extra/clang-doc/Mapper.h
+++ clang-tools-extra/clang-doc/Mapper.h
@@ -44,7 +44,9 @@
   template <typename T> bool mapDecl(const T *D);
 
   int getLine(const NamedDecl *D, const ASTContext &Context) const;
-  StringRef getFile(const NamedDecl *D, const ASTContext &Context) const;
+  llvm::SmallString<128> getFile(const NamedDecl *D, const ASTContext &Context,
+                                 StringRef RootDir,
+                                 bool &IsFileInRootDir) const;
   comments::FullComment *getComment(const NamedDecl *D,
                                     const ASTContext &Context) const;
 
Index: clang-tools-extra/clang-doc/Mapper.cpp
===================================================================
--- clang-tools-extra/clang-doc/Mapper.cpp
+++ clang-tools-extra/clang-doc/Mapper.cpp
@@ -36,10 +36,11 @@
   // If there is an error generating a USR for the decl, skip this decl.
   if (index::generateUSRForDecl(D, USR))
     return true;
-
-  auto I = serialize::emitInfo(
-      D, getComment(D, D->getASTContext()), getLine(D, D->getASTContext()),
-      getFile(D, D->getASTContext()), CDCtx.PublicOnly);
+  bool IsFileInRootDir;
+  auto File = getFile(D, D->getASTContext(), CDCtx.RootDir, IsFileInRootDir);
+  auto I = serialize::emitInfo(D, getComment(D, D->getASTContext()),
+                               getLine(D, D->getASTContext()), File,
+                               IsFileInRootDir, CDCtx.PublicOnly);
 
   // A null in place of I indicates that the serializer is skipping this decl
   // for some reason (e.g. we're only reporting public decls).
@@ -87,11 +88,22 @@
   return Context.getSourceManager().getPresumedLoc(D->getBeginLoc()).getLine();
 }
 
-llvm::StringRef MapASTVisitor::getFile(const NamedDecl *D,
-                                       const ASTContext &Context) const {
-  return Context.getSourceManager()
-      .getPresumedLoc(D->getBeginLoc())
-      .getFilename();
+llvm::SmallString<128> MapASTVisitor::getFile(const NamedDecl *D,
+                                              const ASTContext &Context,
+                                              llvm::StringRef RootDir,
+                                              bool &IsFileInRootDir) const {
+  llvm::SmallString<128> File(Context.getSourceManager()
+                                  .getPresumedLoc(D->getBeginLoc())
+                                  .getFilename());
+  IsFileInRootDir = false;
+  if (RootDir.empty() || !File.startswith(RootDir))
+    return File;
+  IsFileInRootDir = true;
+  llvm::SmallString<128> Prefix(RootDir);
+  if (!llvm::sys::path::is_separator(Prefix.back()))
+    Prefix += llvm::sys::path::get_separator();
+  llvm::sys::path::replace_path_prefix(File, Prefix, "");
+  return File;
 }
 
 } // namespace doc
Index: clang-tools-extra/clang-doc/Representation.h
===================================================================
--- clang-tools-extra/clang-doc/Representation.h
+++ clang-tools-extra/clang-doc/Representation.h
@@ -195,6 +195,9 @@
   Location() = default;
   Location(int LineNumber, SmallString<16> Filename)
       : LineNumber(LineNumber), Filename(std::move(Filename)) {}
+  Location(int LineNumber, SmallString<16> Filename, bool IsFileInRootDir)
+      : LineNumber(LineNumber), Filename(std::move(Filename)),
+        IsFileInRootDir(IsFileInRootDir) {}
 
   bool operator==(const Location &Other) const {
     return std::tie(LineNumber, Filename) ==
@@ -210,8 +213,9 @@
            std::tie(Other.LineNumber, Other.Filename);
   }
 
-  int LineNumber;           // Line number of this Location.
-  SmallString<32> Filename; // File for this Location.
+  int LineNumber;               // Line number of this Location.
+  SmallString<32> Filename;     // File for this Location.
+  bool IsFileInRootDir = false; // Indicates if file is inside root directory
 };
 
 /// A base struct for Infos.
@@ -351,6 +355,8 @@
   bool PublicOnly;
   std::string OutDirectory;
   std::vector<std::string> UserStylesheets;
+  std::string RootDir;
+  std::string RepositoryUrl;
 };
 
 } // namespace doc
Index: clang-tools-extra/clang-doc/Serialize.h
===================================================================
--- clang-tools-extra/clang-doc/Serialize.h
+++ clang-tools-extra/clang-doc/Serialize.h
@@ -38,19 +38,19 @@
 // nullptr.
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const NamespaceDecl *D, const FullComment *FC, int LineNumber,
-         StringRef File, bool PublicOnly);
+         StringRef File, bool IsFileInRootDir, bool PublicOnly);
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const RecordDecl *D, const FullComment *FC, int LineNumber,
-         StringRef File, bool PublicOnly);
+         StringRef File, bool IsFileInRootDir, bool PublicOnly);
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const EnumDecl *D, const FullComment *FC, int LineNumber,
-         StringRef File, bool PublicOnly);
+         StringRef File, bool IsFileInRootDir, bool PublicOnly);
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const FunctionDecl *D, const FullComment *FC, int LineNumber,
-         StringRef File, bool PublicOnly);
+         StringRef File, bool IsFileInRootDir, bool PublicOnly);
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const CXXMethodDecl *D, const FullComment *FC, int LineNumber,
-         StringRef File, bool PublicOnly);
+         StringRef File, bool IsFileInRootDir, bool PublicOnly);
 
 // Function to hash a given USR value for storage.
 // As USRs (Unified Symbol Resolution) could be large, especially for functions
Index: clang-tools-extra/clang-doc/Serialize.cpp
===================================================================
--- clang-tools-extra/clang-doc/Serialize.cpp
+++ clang-tools-extra/clang-doc/Serialize.cpp
@@ -348,19 +348,21 @@
 template <typename T>
 static void populateSymbolInfo(SymbolInfo &I, const T *D, const FullComment *C,
                                int LineNumber, StringRef Filename,
+                               bool IsFileInRootDir,
                                bool &IsInAnonymousNamespace) {
   populateInfo(I, D, C, IsInAnonymousNamespace);
   if (D->isThisDeclarationADefinition())
-    I.DefLoc.emplace(LineNumber, Filename);
+    I.DefLoc.emplace(LineNumber, Filename, IsFileInRootDir);
   else
-    I.Loc.emplace_back(LineNumber, Filename);
+    I.Loc.emplace_back(LineNumber, Filename, IsFileInRootDir);
 }
 
 static void populateFunctionInfo(FunctionInfo &I, const FunctionDecl *D,
                                  const FullComment *FC, int LineNumber,
-                                 StringRef Filename,
+                                 StringRef Filename, bool IsFileInRootDir,
                                  bool &IsInAnonymousNamespace) {
-  populateSymbolInfo(I, D, FC, LineNumber, Filename, IsInAnonymousNamespace);
+  populateSymbolInfo(I, D, FC, LineNumber, Filename, IsFileInRootDir,
+                     IsInAnonymousNamespace);
   if (const auto *T = getDeclForType(D->getReturnType())) {
     if (dyn_cast<EnumDecl>(T))
       I.ReturnType = TypeInfo(getUSRForDecl(T), T->getNameAsString(),
@@ -376,7 +378,7 @@
 
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const NamespaceDecl *D, const FullComment *FC, int LineNumber,
-         llvm::StringRef File, bool PublicOnly) {
+         llvm::StringRef File, bool IsFileInRootDir, bool PublicOnly) {
   auto I = llvm::make_unique<NamespaceInfo>();
   bool IsInAnonymousNamespace = false;
   populateInfo(*I, D, FC, IsInAnonymousNamespace);
@@ -402,10 +404,11 @@
 
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const RecordDecl *D, const FullComment *FC, int LineNumber,
-         llvm::StringRef File, bool PublicOnly) {
+         llvm::StringRef File, bool IsFileInRootDir, bool PublicOnly) {
   auto I = llvm::make_unique<RecordInfo>();
   bool IsInAnonymousNamespace = false;
-  populateSymbolInfo(*I, D, FC, LineNumber, File, IsInAnonymousNamespace);
+  populateSymbolInfo(*I, D, FC, LineNumber, File, IsFileInRootDir,
+                     IsInAnonymousNamespace);
   if (PublicOnly && ((IsInAnonymousNamespace ||
                       !isPublic(D->getAccess(), D->getLinkageInternal()))))
     return {};
@@ -452,10 +455,11 @@
 
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const FunctionDecl *D, const FullComment *FC, int LineNumber,
-         llvm::StringRef File, bool PublicOnly) {
+         llvm::StringRef File, bool IsFileInRootDir, bool PublicOnly) {
   FunctionInfo Func;
   bool IsInAnonymousNamespace = false;
-  populateFunctionInfo(Func, D, FC, LineNumber, File, IsInAnonymousNamespace);
+  populateFunctionInfo(Func, D, FC, LineNumber, File, IsFileInRootDir,
+                       IsInAnonymousNamespace);
   if (PublicOnly && ((IsInAnonymousNamespace ||
                       !isPublic(D->getAccess(), D->getLinkageInternal()))))
     return {};
@@ -477,10 +481,11 @@
 
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const CXXMethodDecl *D, const FullComment *FC, int LineNumber,
-         llvm::StringRef File, bool PublicOnly) {
+         llvm::StringRef File, bool IsFileInRootDir, bool PublicOnly) {
   FunctionInfo Func;
   bool IsInAnonymousNamespace = false;
-  populateFunctionInfo(Func, D, FC, LineNumber, File, IsInAnonymousNamespace);
+  populateFunctionInfo(Func, D, FC, LineNumber, File, IsFileInRootDir,
+                       IsInAnonymousNamespace);
   if (PublicOnly && ((IsInAnonymousNamespace ||
                       !isPublic(D->getAccess(), D->getLinkageInternal()))))
     return {};
@@ -511,10 +516,11 @@
 
 std::pair<std::unique_ptr<Info>, std::unique_ptr<Info>>
 emitInfo(const EnumDecl *D, const FullComment *FC, int LineNumber,
-         llvm::StringRef File, bool PublicOnly) {
+         llvm::StringRef File, bool IsFileInRootDir, bool PublicOnly) {
   EnumInfo Enum;
   bool IsInAnonymousNamespace = false;
-  populateSymbolInfo(Enum, D, FC, LineNumber, File, IsInAnonymousNamespace);
+  populateSymbolInfo(Enum, D, FC, LineNumber, File, IsFileInRootDir,
+                     IsInAnonymousNamespace);
   if (PublicOnly && ((IsInAnonymousNamespace ||
                       !isPublic(D->getAccess(), D->getLinkageInternal()))))
     return {};
Index: clang-tools-extra/clang-doc/tool/ClangDocMain.cpp
===================================================================
--- clang-tools-extra/clang-doc/tool/ClangDocMain.cpp
+++ clang-tools-extra/clang-doc/tool/ClangDocMain.cpp
@@ -67,6 +67,19 @@
     llvm::cl::desc("CSS stylesheets to extend the default styles."),
     llvm::cl::cat(ClangDocCategory));
 
+static llvm::cl::opt<std::string> RootDirectory(
+    "root-directory",
+    llvm::cl::desc(
+        "Directory where processed files are stored. Links to definition "
+        "locations will only be generated if the file is in this dir."),
+    llvm::cl::cat(ClangDocCategory));
+
+static llvm::cl::opt<std::string>
+    RepositoryUrl("repository",
+                  llvm::cl::desc("URL of repository that hosts code; used for "
+                                 "links to definition locations."),
+                  llvm::cl::cat(ClangDocCategory));
+
 enum OutputFormatTy {
   md,
   yaml,
@@ -133,7 +146,7 @@
 // <root>/A/B/C.<ext>
 //
 // namespace A {
-// namesapce B {
+// namespace B {
 //
 // class C {};
 //
@@ -206,11 +219,21 @@
                                   tooling::ArgumentInsertPosition::END),
         ArgAdjuster);
 
+  llvm::SmallString<128> RootDir(RootDirectory);
+  if (RootDir.empty())
+    llvm::sys::fs::current_path(RootDir);
+
+  if (!RepositoryUrl.empty() && RepositoryUrl.find("http://") != 0 &&
+      RepositoryUrl.find("https://") != 0)
+    RepositoryUrl.insert(0, "http://");
+
   clang::doc::ClangDocContext CDCtx = {
       Exec->get()->getExecutionContext(),
       PublicOnly,
       OutDirectory,
-      {UserStylesheets.begin(), UserStylesheets.end()}};
+      {UserStylesheets.begin(), UserStylesheets.end()},
+      RootDir.str(),
+      RepositoryUrl};
 
   if (Format == "html") {
     void *MainAddr = (void *)(intptr_t)GetExecutablePath;
Index: clang-tools-extra/unittests/clang-doc/HTMLGeneratorTest.cpp
===================================================================
--- clang-tools-extra/unittests/clang-doc/HTMLGeneratorTest.cpp
+++ clang-tools-extra/unittests/clang-doc/HTMLGeneratorTest.cpp
@@ -22,12 +22,14 @@
 }
 
 ClangDocContext
-getClangDocContext(std::vector<std::string> UserStylesheets = {}) {
+getClangDocContext(std::vector<std::string> UserStylesheets = {},
+                   StringRef RepositoryUrl = "") {
   ClangDocContext CDCtx;
   CDCtx.UserStylesheets = {UserStylesheets.begin(), UserStylesheets.end()};
   CDCtx.UserStylesheets.insert(
       CDCtx.UserStylesheets.begin(),
       "../share/clang/clang-doc-default-stylesheet.css");
+  CDCtx.RepositoryUrl = RepositoryUrl;
   return CDCtx;
 }
 
@@ -87,7 +89,7 @@
   I.Path = "X/Y/Z";
   I.Namespace.emplace_back(EmptySID, "A", InfoType::IT_namespace);
 
-  I.DefLoc = Location(10, llvm::SmallString<16>{"test.cpp"});
+  I.DefLoc = Location(10, llvm::SmallString<16>{"dir/test.cpp"}, true);
   I.Loc.emplace_back(12, llvm::SmallString<16>{"test.cpp"});
 
   SmallString<16> PathTo;
@@ -107,7 +109,7 @@
   assert(G);
   std::string Buffer;
   llvm::raw_string_ostream Actual(Buffer);
-  ClangDocContext CDCtx = getClangDocContext();
+  ClangDocContext CDCtx = getClangDocContext({}, "https://www.repository.com");
   auto Err = G->generateDocForInfo(&I, Actual, CDCtx);
   assert(!Err);
   std::string Expected = R"raw(<!DOCTYPE html>
@@ -116,7 +118,12 @@
 <link rel="stylesheet" href="../../../clang-doc-default-stylesheet.css"/>
 <div>
   <h1>class r</h1>
-  <p>Defined at line 10 of test.cpp</p>
+  <p>
+    Defined at line 
+    <a href="https://www.repository.com/dir/test.cpp#10">10</a>
+     of file 
+    <a href="https://www.repository.com/dir/test.cpp">test.cpp</a>
+  </p>
   <p>
     Inherits from 
     <a href="../../../path/to/F.html">F</a>
@@ -154,7 +161,7 @@
   I.Name = "f";
   I.Namespace.emplace_back(EmptySID, "A", InfoType::IT_namespace);
 
-  I.DefLoc = Location(10, llvm::SmallString<16>{"test.cpp"});
+  I.DefLoc = Location(10, llvm::SmallString<16>{"dir/test.cpp"}, false);
   I.Loc.emplace_back(12, llvm::SmallString<16>{"test.cpp"});
 
   SmallString<16> PathTo;
@@ -168,7 +175,7 @@
   assert(G);
   std::string Buffer;
   llvm::raw_string_ostream Actual(Buffer);
-  ClangDocContext CDCtx = getClangDocContext();
+  ClangDocContext CDCtx = getClangDocContext({}, "https://www.repository.com");
   auto Err = G->generateDocForInfo(&I, Actual, CDCtx);
   assert(!Err);
   std::string Expected = R"raw(<!DOCTYPE html>
@@ -183,7 +190,7 @@
     <a href="path/to/int.html">int</a>
      P)
   </p>
-  <p>Defined at line 10 of test.cpp</p>
+  <p>Defined at line 10 of file dir/test.cpp</p>
 </div>
 )raw";
 
@@ -217,7 +224,7 @@
   <ul>
     <li>X</li>
   </ul>
-  <p>Defined at line 10 of test.cpp</p>
+  <p>Defined at line 10 of file test.cpp</p>
 </div>
 )raw";
 
@@ -284,7 +291,7 @@
 <div>
   <h3>f</h3>
   <p>void f(int I, int J)</p>
-  <p>Defined at line 10 of test.cpp</p>
+  <p>Defined at line 10 of file test.cpp</p>
   <div>
     <div>
       <p> Brief description.</p>
Index: clang-tools-extra/unittests/clang-doc/SerializeTest.cpp
===================================================================
--- clang-tools-extra/unittests/clang-doc/SerializeTest.cpp
+++ clang-tools-extra/unittests/clang-doc/SerializeTest.cpp
@@ -37,7 +37,7 @@
 
   template <typename T> bool mapDecl(const T *D) {
     auto I = serialize::emitInfo(D, getComment(D), /*Line=*/0,
-                                 /*File=*/"test.cpp", Public);
+                                 /*File=*/"test.cpp", true, Public);
     if (I.first)
       EmittedInfos.emplace_back(std::move(I.first));
     if (I.second)