diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake b/llvm/cmake/modules/HandleLLVMOptions.cmake
--- a/llvm/cmake/modules/HandleLLVMOptions.cmake
+++ b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -846,7 +846,7 @@
 endif()
 
 macro(append_common_sanitizer_flags)
-  if (NOT MSVC)
+  if (NOT MSVC OR CLANG_CL)
     # Append -fno-omit-frame-pointer and turn on debug info to get better
     # stack traces.
     add_flag_if_supported("-fno-omit-frame-pointer" FNO_OMIT_FRAME_POINTER)
@@ -925,23 +925,18 @@
       message(FATAL_ERROR "This sanitizer not yet supported in a MinGW environment: ${LLVM_USE_SANITIZER}")
     endif()
   elseif(MSVC)
-    if (LLVM_USE_SANITIZER STREQUAL "Address")
-      append_common_sanitizer_flags()
-      append("/fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
-      if (NOT CLANG_CL)
-        # Not compatible with /RTC flags.
-        foreach (flags_opt_to_scrub
-            CMAKE_CXX_FLAGS_${uppercase_CMAKE_BUILD_TYPE} CMAKE_C_FLAGS_${uppercase_CMAKE_BUILD_TYPE})
-          string (REGEX REPLACE "(^| )/RTC[1csu]*($| )" " "
-            "${flags_opt_to_scrub}" "${${flags_opt_to_scrub}}")
-        endforeach()
+    if (NOT LLVM_USE_SANITIZER MATCHES "^(Address|Undefined|Address;Undefined|Undefined;Address)$")
+      message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}")
+    endif()
+    append_common_sanitizer_flags()
+    if (LINKER_IS_LLD_LINK)
+      if (LLVM_HOST_TRIPLE MATCHES "i[2-6]86-.*")
+        set(arch "i386")
+      else()
+        set(arch "x86_64")
       endif()
-      if (LINKER_IS_LLD_LINK)
-        if (LLVM_HOST_TRIPLE MATCHES "i[2-6]86-.*")
-          set(arch "i386")
-        else()
-          set(arch "x86_64")
-        endif()
+      # Prepare ASAN runtime if needed
+      if (LLVM_USE_SANITIZER MATCHES ".*Address.*")
         if (${LLVM_USE_CRT_${uppercase_CMAKE_BUILD_TYPE}} MATCHES "^(MT|MTd)$")
           append("/wholearchive:clang_rt.asan-${arch}.lib /wholearchive:clang_rt.asan_cxx-${arch}.lib"
             CMAKE_EXE_LINKER_FLAGS)
@@ -952,8 +947,26 @@
             CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
         endif()
       endif()
-    else()
-      message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}")
+    endif()
+    if (LLVM_USE_SANITIZER MATCHES ".*Address.*")
+      if (NOT CLANG_CL)
+        append("/fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+        # Not compatible with /RTC flags.
+        foreach (flags_opt_to_scrub
+            CMAKE_CXX_FLAGS_${uppercase_CMAKE_BUILD_TYPE} CMAKE_C_FLAGS_${uppercase_CMAKE_BUILD_TYPE})
+          string (REGEX REPLACE "(^| )/RTC[1csu]*($| )" " "
+            "${flags_opt_to_scrub}" "${${flags_opt_to_scrub}}")
+        endforeach()
+      else()
+        append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)   
+      endif()     
+    endif()
+    if (LLVM_USE_SANITIZER MATCHES ".*Undefined.*") 
+      if (NOT CLANG_CL)
+        message(FATAL_ERROR "This sanitizer is only supported by clang-cl: Undefined")
+      endif()
+      append("-D_ITERATOR_DEBUG_LEVEL=0" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+      append(${LLVM_UBSAN_FLAGS} CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
     endif()
   else()
     message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.")
diff --git a/llvm/utils/sanitizers/ubsan_ignorelist.txt b/llvm/utils/sanitizers/ubsan_ignorelist.txt
--- a/llvm/utils/sanitizers/ubsan_ignorelist.txt
+++ b/llvm/utils/sanitizers/ubsan_ignorelist.txt
@@ -14,3 +14,10 @@
 # libstdc++ 8.0.1 casts an under-aligned pointer to type type_info:
 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85930
 src:*bits/shared_ptr_base.h
+
+# UBSAN reports false-positive for 0-sized objects
+# https://github.com/llvm/llvm-project/issues/61775
+src:*/ADT/StringMap.h
+src:*/Support/AllocatorBase.h
+src:*/ADT/StringMapEntry.h
+src:*/ADT/SmallPtrSet.h