Index: cfe/trunk/lib/Driver/Tools.cpp
===================================================================
--- cfe/trunk/lib/Driver/Tools.cpp
+++ cfe/trunk/lib/Driver/Tools.cpp
@@ -8948,7 +8948,16 @@
     }
     break;
   case ToolChain::RLT_Libgcc:
-    AddLibgcc(TC.getTriple(), D, CmdArgs, Args);
+    // Make sure libgcc is not used under MSVC environment by default
+    if (TC.getTriple().isKnownWindowsMSVCEnvironment()) {
+      // Issue error diagnostic if libgcc is explicitly specified
+      // through command line as --rtlib option argument.
+      if (Args.hasArg(options::OPT_rtlib_EQ)) {
+        TC.getDriver().Diag(diag::err_drv_unsupported_rtlib_for_platform)
+            << Args.getLastArg(options::OPT_rtlib_EQ)->getValue() << "MSVC";
+      }
+    } else
+      AddLibgcc(TC.getTriple(), D, CmdArgs, Args);
     break;
   }
 }
@@ -9754,6 +9763,12 @@
     }
   }
 
+  // Add compiler-rt lib in case if it was explicitly
+  // specified as an argument for --rtlib option.
+  if (!Args.hasArg(options::OPT_nostdlib)) {
+    AddRunTimeLibs(TC, TC.getDriver(), CmdArgs, Args);
+  }
+
   // Add filenames, libraries, and other linker inputs.
   for (const auto &Input : Inputs) {
     if (Input.isFilename()) {
Index: cfe/trunk/test/Driver/msvc-compiler-rt.c
===================================================================
--- cfe/trunk/test/Driver/msvc-compiler-rt.c
+++ cfe/trunk/test/Driver/msvc-compiler-rt.c
@@ -0,0 +1,5 @@
+// RUN: %clang -target x86_64-pc-windows-msvc --rtlib=compiler-rt -### %s 2>&1 | FileCheck %s -check-prefix MSVC-COMPILER-RT
+// RUN: not %clang %s -target x86_64-pc-windows-msvc --rtlib=libgcc 2>&1 | FileCheck %s -check-prefix CHECK-ERROR
+
+// MSVC-COMPILER-RT: "{{.*}}clang_rt.builtins{{.*}}"
+// CHECK-ERROR: unsupported runtime library 'libgcc' for platform 'MSVC'
Index: cfe/trunk/test/Driver/nostdlib.c
===================================================================
--- cfe/trunk/test/Driver/nostdlib.c
+++ cfe/trunk/test/Driver/nostdlib.c
@@ -22,6 +22,10 @@
 // RUN:     -resource-dir=%S/Inputs/resource_dir -lclang_rt.builtins-i686 \
 // RUN:   | FileCheck --check-prefix=CHECK-LINUX-NOSTDLIB %s
 //
+// RUN: %clang -target x86_64-pc-windows-msvc -nostdlib --rtlib=compiler-rt -### %s 2>&1 | FileCheck %s -check-prefix CHECK-MSVC-NOSTDLIB
+// RUN: %clang -target x86_64-pc-windows-msvc --rtlib=compiler-rt -nostdlib -### %s 2>&1 | FileCheck %s -check-prefix CHECK-MSVC-NOSTDLIB
+//
 // CHECK-LINUX-NOSTDLIB: warning: argument unused during compilation: '--rtlib=compiler-rt'
 // CHECK-LINUX-NOSTDLIB: "{{(.*[^.0-9A-Z_a-z])?}}ld{{(.exe)?}}"
 // CHECK-LINUX-NOSTDLIB-NOT: "{{.*}}/Inputs/resource_dir{{/|\\\\}}lib{{/|\\\\}}linux{{/|\\\\}}libclang_rt.builtins-i686.a"
+// CHECK-MSVC-NOSTDLIB: warning: argument unused during compilation: '--rtlib=compiler-rt'