Index: tools/clang/lib/Driver/MinGWToolChain.cpp
===================================================================
--- tools/clang/lib/Driver/MinGWToolChain.cpp
+++ tools/clang/lib/Driver/MinGWToolChain.cpp
@@ -129,18 +129,20 @@
   if (DriverArgs.hasArg(options::OPT_nostdlibinc))
     return;
 
-  llvm::SmallString<1024> IncludeDir(GccLibDir);
-  llvm::sys::path::append(IncludeDir, "include");
-  addSystemInclude(DriverArgs, CC1Args, IncludeDir.c_str());
-  IncludeDir += "-fixed";
+if (GetRuntimeLibType(DriverArgs) == ToolChain::RLT_Libgcc) {
+    llvm::SmallString<1024> IncludeDir(GccLibDir);
+    llvm::sys::path::append(IncludeDir, "include");
+    addSystemInclude(DriverArgs, CC1Args, IncludeDir.c_str());
+    IncludeDir += "-fixed";
 #ifdef LLVM_ON_UNIX
-  // For openSUSE.
-  addSystemInclude(DriverArgs, CC1Args,
-                   "/usr/x86_64-w64-mingw32/sys-root/mingw/include");
+    // For openSUSE.
+    addSystemInclude(DriverArgs, CC1Args,
+                     "/usr/x86_64-w64-mingw32/sys-root/mingw/include");
 #endif
-  addSystemInclude(DriverArgs, CC1Args, IncludeDir.c_str());
-  addSystemInclude(DriverArgs, CC1Args, Base + Arch + "include");
-  addSystemInclude(DriverArgs, CC1Args, Base + "include");
+    addSystemInclude(DriverArgs, CC1Args, IncludeDir.c_str());
+    addSystemInclude(DriverArgs, CC1Args, Base + Arch + "include");
+    addSystemInclude(DriverArgs, CC1Args, Base + "include");
+  }
 }
 
 void MinGW::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
@@ -149,27 +151,37 @@
       DriverArgs.hasArg(options::OPT_nostdincxx))
     return;
 
-  // C++ includes may be found in several locations depending on distribution.
-  // Windows
-  // -------
-  // mingw-w64 mingw-builds: $sysroot/i686-w64-mingw32/include/c++.
-  // mingw-w64 msys2:        $sysroot/include/c++/4.9.2
-  // mingw.org:              GccLibDir/include/c++
-  //
-  // Linux
-  // -----
-  // openSUSE:               GccLibDir/include/c++
-  llvm::SmallVector<llvm::SmallString<1024>, 3> CppIncludeBases;
-  CppIncludeBases.emplace_back(Base);
-  llvm::sys::path::append(CppIncludeBases[0], Arch, "include", "c++");
-  CppIncludeBases.emplace_back(Base);
-  llvm::sys::path::append(CppIncludeBases[1], "include", "c++", Ver);
-  CppIncludeBases.emplace_back(GccLibDir);
-  llvm::sys::path::append(CppIncludeBases[2], "include", "c++");
-  for (auto &CppIncludeBase : CppIncludeBases) {
-    CppIncludeBase += llvm::sys::path::get_separator();
-    addSystemInclude(DriverArgs, CC1Args, CppIncludeBase);
-    addSystemInclude(DriverArgs, CC1Args, CppIncludeBase + Arch);
-    addSystemInclude(DriverArgs, CC1Args, CppIncludeBase + "backward");
+  switch (GetCXXStdlibType(DriverArgs)) {
+  case ToolChain::CST_Libcxx:
+    addSystemInclude(DriverArgs, CC1Args, Base        + "include" +
+                     llvm::sys::path::get_separator() + "c++"     +
+                     llvm::sys::path::get_separator() + "v1");
+    break;
+
+  case ToolChain::CST_Libstdcxx:
+    // C++ includes may be found in several locations depending on distribution.
+    // Windows
+    // -------
+    // mingw-w64 mingw-builds: $sysroot/i686-w64-mingw32/include/c++.
+    // mingw-w64 msys2:        $sysroot/include/c++/4.9.2
+    // mingw.org:              GccLibDir/include/c++
+    //
+    // Linux
+    // -----
+    // openSUSE:               GccLibDir/include/c++
+    llvm::SmallVector<llvm::SmallString<1024>, 3> CppIncludeBases;
+    CppIncludeBases.emplace_back(Base);
+    llvm::sys::path::append(CppIncludeBases[0], Arch, "include", "c++");
+    CppIncludeBases.emplace_back(Base);
+    llvm::sys::path::append(CppIncludeBases[1], "include", "c++", Ver);
+    CppIncludeBases.emplace_back(GccLibDir);
+    llvm::sys::path::append(CppIncludeBases[2], "include", "c++");
+    for (auto &CppIncludeBase : CppIncludeBases) {
+      CppIncludeBase += llvm::sys::path::get_separator();
+      addSystemInclude(DriverArgs, CC1Args, CppIncludeBase);
+      addSystemInclude(DriverArgs, CC1Args, CppIncludeBase + Arch);
+      addSystemInclude(DriverArgs, CC1Args, CppIncludeBase + "backward");
+    }
+    break;
   }
 }
Index: tools/clang/lib/Driver/Tools.h
===================================================================
--- tools/clang/lib/Driver/Tools.h
+++ tools/clang/lib/Driver/Tools.h
@@ -689,7 +689,7 @@
                     const char *LinkingOutput) const override;
 
 private:
-  void AddLibGCC(const llvm::opt::ArgList &Args, ArgStringList &CmdArgs) const;
+  void AddRuntime(const ToolChain &TC, const llvm::opt::ArgList &Args, ArgStringList &CmdArgs) const;
 };
 } // end namespace MinGW
 
Index: tools/clang/lib/Driver/Tools.cpp
===================================================================
--- tools/clang/lib/Driver/Tools.cpp
+++ tools/clang/lib/Driver/Tools.cpp
@@ -2243,8 +2243,7 @@
 
 // Until ARM libraries are build separately, we have them all in one library
 static StringRef getArchNameForCompilerRTLib(const ToolChain &TC) {
-  if (TC.getTriple().isOSWindows() &&
-      !TC.getTriple().isWindowsItaniumEnvironment() &&
+  if (TC.getTriple().isWindowsMSVCEnvironment() &&
       TC.getArch() == llvm::Triple::x86)
     return "i386";
   if (TC.getArch() == llvm::Triple::arm || TC.getArch() == llvm::Triple::armeb)
@@ -2269,11 +2268,12 @@
                         ? "-android"
                         : "";
 
-  bool IsOSWindows = TC.getTriple().isOSWindows();
+  bool IsITANMSVCWindows = TC.getTriple().isWindowsMSVCEnvironment() ||
+                           TC.getTriple().isWindowsItaniumEnvironment();
   StringRef Arch = getArchNameForCompilerRTLib(TC);
-  const char *Prefix = IsOSWindows ? "" : "lib";
+  const char *Prefix = IsITANMSVCWindows ? "" : "lib";
   const char *Suffix =
-      Shared ? (IsOSWindows ? ".dll" : ".so") : (IsOSWindows ? ".lib" : ".a");
+      Shared ? (IsOSWindows ? ".dll" : ".so") : (IsITANMSVCWindows ? ".lib" : ".a");
 
   SmallString<128> Path = getCompilerRTLibDir(TC);
   llvm::sys::path::append(Path, Prefix + Twine("clang_rt.") + Component + "-" +
@@ -8905,20 +8905,30 @@
                    SplitDebugName(Args, Inputs[0]));
 }
 
-void MinGW::Linker::AddLibGCC(const ArgList &Args,
-                              ArgStringList &CmdArgs) const {
+void MinGW::Linker::AddRuntime(const ToolChain &TC, const ArgList &Args,
+                               ArgStringList &CmdArgs) const {
   if (Args.hasArg(options::OPT_mthreads))
     CmdArgs.push_back("-lmingwthrd");
   CmdArgs.push_back("-lmingw32");
-  if (Args.hasArg(options::OPT_shared) ||
-      Args.hasArg(options::OPT_shared_libgcc) ||
-      !Args.hasArg(options::OPT_static_libgcc)) {
-    CmdArgs.push_back("-lgcc_s");
-    CmdArgs.push_back("-lgcc");
-  } else {
-    CmdArgs.push_back("-lgcc");
-    CmdArgs.push_back("-lgcc_eh");
+
+  switch (TC.GetRuntimeLibType(Args)) {
+  case ToolChain::RLT_CompilerRT:
+    CmdArgs.push_back(Args.MakeArgString(getCompilerRT(TC, "builtins")));
+    break;
+
+  case ToolChain::RLT_Libgcc:
+    if (Args.hasArg(options::OPT_shared) ||
+        Args.hasArg(options::OPT_shared_libgcc) ||
+        !Args.hasArg(options::OPT_static_libgcc)) {
+      CmdArgs.push_back("-lgcc_s");
+      CmdArgs.push_back("-lgcc");
+    } else {
+      CmdArgs.push_back("-lgcc");
+      CmdArgs.push_back("-lgcc_eh");
+    }
+    break;
   }
+
   CmdArgs.push_back("-lmoldname");
   CmdArgs.push_back("-lmingwex");
   CmdArgs.push_back("-lmsvcrt");
@@ -9051,7 +9061,7 @@
       if (Args.hasArg(options::OPT_fopenmp))
         CmdArgs.push_back("-lgomp");
 
-      AddLibGCC(Args, CmdArgs);
+      AddRuntime(TC, Args, CmdArgs);
 
       if (Args.hasArg(options::OPT_pg))
         CmdArgs.push_back("-lgmon");
@@ -9072,7 +9082,7 @@
       if (Args.hasArg(options::OPT_static))
         CmdArgs.push_back("--end-group");
       else if (!LinkerName.equals_lower("lld"))
-        AddLibGCC(Args, CmdArgs);
+        AddRuntime(TC, Args, CmdArgs);
     }
 
     if (!Args.hasArg(options::OPT_nostartfiles)) {