diff --git a/compiler-rt/cmake/config-ix.cmake b/compiler-rt/cmake/config-ix.cmake
--- a/compiler-rt/cmake/config-ix.cmake
+++ b/compiler-rt/cmake/config-ix.cmake
@@ -121,9 +121,12 @@
 check_cxx_compiler_flag(-Wno-format COMPILER_RT_HAS_WNO_FORMAT)
 check_cxx_compiler_flag(-Wno-format-pedantic COMPILER_RT_HAS_WNO_FORMAT_PEDANTIC)
 
+check_cxx_compiler_flag("/experimental:external /external:W0" COMPILER_RT_HAS_EXTERNAL_FLAG)
+
 check_cxx_compiler_flag(/W4 COMPILER_RT_HAS_W4_FLAG)
 check_cxx_compiler_flag(/WX COMPILER_RT_HAS_WX_FLAG)
 check_cxx_compiler_flag(/wd4146 COMPILER_RT_HAS_WD4146_FLAG)
+check_cxx_compiler_flag(/wd4206 COMPILER_RT_HAS_WD4206_FLAG)
 check_cxx_compiler_flag(/wd4291 COMPILER_RT_HAS_WD4291_FLAG)
 check_cxx_compiler_flag(/wd4221 COMPILER_RT_HAS_WD4221_FLAG)
 check_cxx_compiler_flag(/wd4391 COMPILER_RT_HAS_WD4391_FLAG)
diff --git a/compiler-rt/lib/asan/CMakeLists.txt b/compiler-rt/lib/asan/CMakeLists.txt
--- a/compiler-rt/lib/asan/CMakeLists.txt
+++ b/compiler-rt/lib/asan/CMakeLists.txt
@@ -90,6 +90,9 @@
 
 append_rtti_flag(OFF ASAN_CFLAGS)
 
+# Silence warnings in system headers with MSVC.
+append_list_if(COMPILER_RT_HAS_EXTERNAL_FLAG "/experimental:external /external:W0 /external:anglebrackets" ASAN_CFLAGS)
+
 # Too many existing bugs, needs cleanup.
 append_list_if(COMPILER_RT_HAS_WNO_FORMAT -Wno-format ASAN_CFLAGS)
 
diff --git a/compiler-rt/lib/asan/asan_win_dll_thunk.cpp b/compiler-rt/lib/asan/asan_win_dll_thunk.cpp
--- a/compiler-rt/lib/asan/asan_win_dll_thunk.cpp
+++ b/compiler-rt/lib/asan/asan_win_dll_thunk.cpp
@@ -56,6 +56,13 @@
 
 // TODO(timurrrr): Do we need to add _Crt* stuff here? (see asan_malloc_win.cpp)
 
+#  if defined(_MSC_VER) && !defined(__clang__)
+// Disable warnings such as: 'void memchr(void)': incorrect number of arguments
+// for intrinsic function, expected '3' arguments.
+#    pragma warning(push)
+#    pragma warning(disable : 4392)
+#  endif
+
 INTERCEPT_LIBRARY_FUNCTION(atoi);
 INTERCEPT_LIBRARY_FUNCTION(atol);
 INTERCEPT_LIBRARY_FUNCTION(frexp);
@@ -87,6 +94,10 @@
 INTERCEPT_LIBRARY_FUNCTION(wcslen);
 INTERCEPT_LIBRARY_FUNCTION(wcsnlen);
 
+#  if defined(_MSC_VER) && !defined(__clang__)
+#    pragma warning(pop)
+#  endif
+
 #ifdef _WIN64
 INTERCEPT_LIBRARY_FUNCTION(__C_specific_handler);
 #else
diff --git a/compiler-rt/lib/builtins/cpu_model.c b/compiler-rt/lib/builtins/cpu_model.c
--- a/compiler-rt/lib/builtins/cpu_model.c
+++ b/compiler-rt/lib/builtins/cpu_model.c
@@ -13,6 +13,10 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef __has_attribute
+#define __has_attribute(attr) 0
+#endif
+
 #if defined(HAVE_INIT_PRIORITY)
 #define CONSTRUCTOR_ATTRIBUTE __attribute__((__constructor__ 101))
 #elif __has_attribute(__constructor__)
@@ -37,10 +41,6 @@
 #include <intrin.h>
 #endif
 
-#ifndef __has_attribute
-#define __has_attribute(attr) 0
-#endif
-
 enum VendorSignatures {
   SIG_INTEL = 0x756e6547, // Genu
   SIG_AMD = 0x68747541,   // Auth
diff --git a/compiler-rt/lib/builtins/emutls.c b/compiler-rt/lib/builtins/emutls.c
--- a/compiler-rt/lib/builtins/emutls.c
+++ b/compiler-rt/lib/builtins/emutls.c
@@ -30,7 +30,7 @@
 // MSVC raises a warning about a nonstandard extension being used for the 0
 // sized element in this array. Disable this for warn-as-error builds.
 #pragma warning(push)
-#pragma warning(disable : 4206)
+#pragma warning(disable : 4200)
 #endif
 
 typedef struct emutls_address_array {
diff --git a/compiler-rt/lib/builtins/udivmoddi4.c b/compiler-rt/lib/builtins/udivmoddi4.c
--- a/compiler-rt/lib/builtins/udivmoddi4.c
+++ b/compiler-rt/lib/builtins/udivmoddi4.c
@@ -21,7 +21,7 @@
 // MSVC throws a warning about mod 0 here, disable it for builds that
 // warn-as-error
 #pragma warning(push)
-#pragma warning(disable : 4724)
+#pragma warning(disable : 4724 4723)
 #endif
 
 COMPILER_RT_ABI du_int __udivmoddi4(du_int a, du_int b, du_int *rem) {
diff --git a/compiler-rt/lib/interception/CMakeLists.txt b/compiler-rt/lib/interception/CMakeLists.txt
--- a/compiler-rt/lib/interception/CMakeLists.txt
+++ b/compiler-rt/lib/interception/CMakeLists.txt
@@ -19,6 +19,9 @@
 set(INTERCEPTION_CFLAGS ${SANITIZER_COMMON_CFLAGS})
 append_rtti_flag(OFF INTERCEPTION_CFLAGS)
 
+# Silence warnings in system headers with MSVC.
+append_list_if(COMPILER_RT_HAS_EXTERNAL_FLAG "/experimental:external /external:W0 /external:anglebrackets" INTERCEPTION_CFLAGS)
+
 add_compiler_rt_object_libraries(RTInterception
     OS ${SANITIZER_COMMON_SUPPORTED_OS}
     ARCHS ${SANITIZER_COMMON_SUPPORTED_ARCH}
diff --git a/compiler-rt/lib/profile/CMakeLists.txt b/compiler-rt/lib/profile/CMakeLists.txt
--- a/compiler-rt/lib/profile/CMakeLists.txt
+++ b/compiler-rt/lib/profile/CMakeLists.txt
@@ -80,7 +80,7 @@
 if(WIN32)
   list(APPEND PROFILE_SOURCES
     WindowsMMap.c
-    )
+  )
 endif()
 
 include_directories(..)
@@ -120,6 +120,9 @@
 # nonstandard extension used : 'identifier' : cannot be initialized using address of automatic variable
 append_list_if(COMPILER_RT_HAS_WD4221_FLAG /wd4221 EXTRA_FLAGS)
 
+# Disable 'nonstandard extension used: translation unit is empty'.
+append_list_if(COMPILER_RT_HAS_WD4206_FLAG /wd4206 EXTRA_FLAGS)
+
 if(APPLE)
   add_compiler_rt_runtime(clang_rt.profile
     STATIC
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_stack_store.cpp
@@ -234,6 +234,11 @@
   return to;
 }
 
+#if defined(_MSC_VER) && !defined(__clang__)
+#  pragma warning(push)
+// Disable 'nonstandard extension used: zero-sized array in struct/union'.
+#  pragma warning(disable : 4200)
+#endif
 namespace {
 struct PackedHeader {
   uptr size;
@@ -241,6 +246,9 @@
   u8 data[];
 };
 }  // namespace
+#if defined(_MSC_VER) && !defined(__clang__)
+#  pragma warning(pop)
+#endif
 
 uptr *StackStore::BlockInfo::GetOrUnpack(StackStore *store) {
   SpinMutexLock l(&mtx_);
diff --git a/compiler-rt/lib/ubsan/CMakeLists.txt b/compiler-rt/lib/ubsan/CMakeLists.txt
--- a/compiler-rt/lib/ubsan/CMakeLists.txt
+++ b/compiler-rt/lib/ubsan/CMakeLists.txt
@@ -55,6 +55,9 @@
 append_rtti_flag(ON UBSAN_CXXFLAGS)
 append_list_if(SANITIZER_CAN_USE_CXXABI -DUBSAN_CAN_USE_CXXABI UBSAN_CXXFLAGS)
 
+# Silence warnings in system headers with MSVC.
+append_list_if(COMPILER_RT_HAS_EXTERNAL_FLAG "/experimental:external /external:W0 /external:anglebrackets" UBSAN_CXXFLAGS)
+
 set(UBSAN_LINK_FLAGS ${SANITIZER_COMMON_LINK_FLAGS})
 
 set(UBSAN_DYNAMIC_LIBS ${SANITIZER_CXX_ABI_LIBRARIES} ${SANITIZER_COMMON_LINK_LIBS})