Index: include/clang/Driver/SanitizerArgs.h
===================================================================
--- include/clang/Driver/SanitizerArgs.h
+++ include/clang/Driver/SanitizerArgs.h
@@ -10,6 +10,7 @@
 #define LLVM_CLANG_DRIVER_SANITIZERARGS_H
 
 #include "clang/Basic/Sanitizers.h"
+#include "clang/Driver/Types.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include <string>
@@ -54,8 +55,8 @@
   bool requiresPIE() const;
   bool needsUnwindTables() const;
   bool linkCXXRuntimes() const { return LinkCXXRuntimes; }
-  void addArgs(const llvm::opt::ArgList &Args,
-               llvm::opt::ArgStringList &CmdArgs) const;
+  void addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
+               llvm::opt::ArgStringList &CmdArgs, types::ID InputType) const;
 
  private:
   void clear();
Index: lib/Driver/SanitizerArgs.cpp
===================================================================
--- lib/Driver/SanitizerArgs.cpp
+++ lib/Driver/SanitizerArgs.cpp
@@ -7,6 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 #include "clang/Driver/SanitizerArgs.h"
+#include "Tools.h"
 #include "clang/Basic/Sanitizers.h"
 #include "clang/Driver/Driver.h"
 #include "clang/Driver/DriverDiagnostic.h"
@@ -533,8 +534,9 @@
   return Res;
 }
 
-void SanitizerArgs::addArgs(const llvm::opt::ArgList &Args,
-                            llvm::opt::ArgStringList &CmdArgs) const {
+void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
+                            llvm::opt::ArgStringList &CmdArgs,
+                            types::ID InputType) const {
   if (Sanitizers.empty())
     return;
   CmdArgs.push_back(Args.MakeArgString("-fsanitize=" + toString(Sanitizers)));
@@ -581,6 +583,17 @@
   // affect compilation.
   if (Sanitizers.has(Memory) || Sanitizers.has(Address))
     CmdArgs.push_back(Args.MakeArgString("-fno-assume-sane-operator-new"));
+
+  if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
+    // Instruct the code generator to embed linker directives in the object file
+    // that cause the required runtime libraries to be linked.
+    CmdArgs.push_back(Args.MakeArgString(
+        "--dependent-lib=" + tools::getCompilerRT(TC, "ubsan_standalone")));
+    if (types::isCXX(InputType))
+      CmdArgs.push_back(
+          Args.MakeArgString("--dependent-lib=" +
+                             tools::getCompilerRT(TC, "ubsan_standalone_cxx")));
+  }
 }
 
 SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
Index: lib/Driver/Tools.h
===================================================================
--- lib/Driver/Tools.h
+++ lib/Driver/Tools.h
@@ -37,6 +37,9 @@
 
 using llvm::opt::ArgStringList;
 
+SmallString<128> getCompilerRT(const ToolChain &TC, StringRef Component,
+                               bool Shared = false);
+
   /// \brief Clang compiler tool.
   class LLVM_LIBRARY_VISIBILITY Clang : public Tool {
   public:
Index: lib/Driver/Tools.cpp
===================================================================
--- lib/Driver/Tools.cpp
+++ lib/Driver/Tools.cpp
@@ -2231,10 +2231,6 @@
 
 // Until ARM libraries are build separately, we have them all in one library
 static StringRef getArchNameForCompilerRTLib(const ToolChain &TC) {
-  // FIXME: handle 64-bit
-  if (TC.getTriple().isOSWindows() &&
-      !TC.getTriple().isWindowsItaniumEnvironment())
-    return "i386";
   if (TC.getArch() == llvm::Triple::arm || TC.getArch() == llvm::Triple::armeb)
     return "arm";
   return TC.getArchName();
@@ -2251,8 +2247,8 @@
   return Res;
 }
 
-static SmallString<128> getCompilerRT(const ToolChain &TC, StringRef Component,
-                                      bool Shared = false) {
+SmallString<128> tools::getCompilerRT(const ToolChain &TC, StringRef Component,
+                                      bool Shared) {
   const char *Env = TC.getTriple().getEnvironment() == llvm::Triple::Android
                         ? "-android"
                         : "";
@@ -3927,7 +3923,7 @@
     }
 
   const SanitizerArgs &Sanitize = getToolChain().getSanitizerArgs();
-  Sanitize.addArgs(Args, CmdArgs);
+  Sanitize.addArgs(getToolChain(), Args, CmdArgs, InputType);
 
   // Report an error for -faltivec on anything other than PowerPC.
   if (const Arg *A = Args.getLastArg(options::OPT_faltivec)) {
Index: test/Driver/cl-link.c
===================================================================
--- test/Driver/cl-link.c
+++ test/Driver/cl-link.c
@@ -11,7 +11,7 @@
 // LINK: "bar"
 // LINK: "baz"
 
-// RUN: %clang_cl /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN %s
+// RUN: %clang_cl -m32 /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN %s
 // ASAN: link.exe
 // ASAN: "-debug"
 // ASAN: "-incremental:no"
@@ -19,7 +19,7 @@
 // ASAN: "{{.*}}clang_rt.asan_cxx-i386.lib"
 // ASAN: "{{.*}}cl-link{{.*}}.obj"
 
-// RUN: %clang_cl /MD /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN-MD %s
+// RUN: %clang_cl -m32 /MD /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN-MD %s
 // ASAN-MD: link.exe
 // ASAN-MD: "-debug"
 // ASAN-MD: "-incremental:no"
@@ -33,8 +33,8 @@
 // DLL: link.exe
 // "-dll"
 
-// RUN: %clang_cl /LD /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN-DLL %s
-// RUN: %clang_cl /LDd /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN-DLL %s
+// RUN: %clang_cl -m32 /LD /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN-DLL %s
+// RUN: %clang_cl -m32 /LDd /Tc%s -### -fsanitize=address 2>&1 | FileCheck --check-prefix=ASAN-DLL %s
 // ASAN-DLL: link.exe
 // ASAN-DLL: "-dll"
 // ASAN-DLL: "-debug"
Index: test/Driver/fsanitize.c
===================================================================
--- test/Driver/fsanitize.c
+++ test/Driver/fsanitize.c
@@ -16,6 +16,15 @@
 // RUN: %clang -target i386-unknown-openbsd -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UNDEFINED-OPENBSD
 // CHECK-UNDEFINED-OPENBSD: "-fsanitize={{((signed-integer-overflow|integer-divide-by-zero|float-divide-by-zero|shift-base|shift-exponent|unreachable|return|vla-bound|alignment|null|object-size|float-cast-overflow|array-bounds|enum|bool|returns-nonnull-attribute|nonnull-attribute),?){17}"}}
 
+// RUN: %clang -target i386-pc-win32 -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UNDEFINED-WIN --check-prefix=CHECK-UNDEFINED-WIN32
+// RUN: %clang -target i386-pc-win32 -fsanitize=undefined -x c++ %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UNDEFINED-WIN --check-prefix=CHECK-UNDEFINED-WIN32 --check-prefix=CHECK-UNDEFINED-WIN-CXX
+// RUN: %clang -target x86_64-pc-win32 -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UNDEFINED-WIN --check-prefix=CHECK-UNDEFINED-WIN64
+// RUN: %clang -target x86_64-pc-win32 -fsanitize=undefined -x c++ %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UNDEFINED-WIN --check-prefix=CHECK-UNDEFINED-WIN64 --check-prefix=CHECK-UNDEFINED-WIN-CXX
+// CHECK-UNDEFINED-WIN: "-fsanitize={{((signed-integer-overflow|integer-divide-by-zero|float-divide-by-zero|shift-base|shift-exponent|unreachable|return|vla-bound|alignment|null|object-size|float-cast-overflow|array-bounds|enum|bool|returns-nonnull-attribute|nonnull-attribute),?){17}"}}
+// CHECK-UNDEFINED-WIN32-SAME: "--dependent-lib={{[^"]*}}ubsan_standalone-i386.lib"
+// CHECK-UNDEFINED-WIN64-SAME: "--dependent-lib={{[^"]*}}ubsan_standalone-x86_64.lib"
+// CHECK-UNDEFINED-WIN-CXX-SAME: "--dependent-lib={{[^"]*}}ubsan_standalone_cxx{{[^"]*}}.lib"
+
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=integer %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-INTEGER
 // CHECK-INTEGER: "-fsanitize={{((signed-integer-overflow|unsigned-integer-overflow|integer-divide-by-zero|shift-base|shift-exponent),?){5}"}}