diff --git a/.github/workflows/es-actions.yml b/.github/workflows/es-actions.yml
index 61220e8ae..9d9633a94 100644
--- a/.github/workflows/es-actions.yml
+++ b/.github/workflows/es-actions.yml
@@ -174,6 +174,57 @@ jobs:
           CC=clang CXX=clang++ cmake -H. -Bout/release -DESCARGOT_ARCH=aarch64 -DESCARGOT_HOST=linux -DESCARGOT_MODE=release -DESCARGOT_TEMPORAL=ON -DESCARGOT_TCO=ON -DESCARGOT_TEST=ON -DESCARGOT_OUTPUT=shell -GNinja
           ninja -Cout/release
           python3 ./tools/run-tests.py --engine="./out/release/escargot" new-es
+  test-on-windows-x86-clang-cl:
+    runs-on: windows-2022
+    strategy:
+      matrix:
+        arch: [x86]
+    steps:
+    - name: Set git cllf config
+      run: |
+        git config --global core.autocrlf input
+        git config --global core.eol lf
+    - uses: actions/checkout@v3
+      with:
+        submodules: true
+    - uses: szenius/set-timezone@v1.2
+      with:
+        timezoneWindows: "Pacific Standard Time"
+    - uses: lukka/get-cmake@latest
+    - uses: GuillaumeFalourd/setup-windows10-sdk-action@v1.11
+      with:
+        sdk-version: 20348
+    - uses: actions/setup-python@v4
+      with:
+        python-version: '3.11'
+    - name: Install msvc redist package
+      run: |
+        (new-object System.Net.WebClient).DownloadFile('https://github.com/abbodi1406/vcredist/releases/download/v0.73.0/VisualCppRedist_AIO_x86_x64.exe','VisualCppRedist_AIO_x86_x64.exe')
+        .\VisualCppRedist_AIO_x86_x64.exe /y
+    - uses: ilammy/msvc-dev-cmd@v1.12.1
+      with:
+        arch: ${{ matrix.arch }}
+        sdk: "10.0.20348.0"
+    - name: Build ${{ matrix.arch }} Release
+      run: |
+        CMake -DCMAKE_SYSTEM_NAME=Windows -DCMAKE_SYSTEM_VERSION:STRING="10.0" -DCMAKE_SYSTEM_PROCESSOR=x86 -DESCARGOT_ARCH=x86 -DESCARGOT_MODE=release -Bout/ -DESCARGOT_HOST=windows -DESCARGOT_OUTPUT=shell -DESCARGOT_LIBICU_SUPPORT=ON -DESCARGOT_LIBICU_SUPPORT_WITH_DLOPEN=NO -DESCARGOT_THREADING=ON -DESCARGOT_TCO=ON -DESCARGOT_TEST=ON -G Ninja -DCMAKE_C_COMPILER=clang-cl -DCMAKE_CXX_COMPILER=clang-cl -DCMAKE_BUILD_TYPE=release -DCMAKE_C_FLAGS="-m32" -DCMAKE_CXX_FLAGS="-m32"
+        CMake --build out/ --config Release
+    # windows internal ICU doesn't support Temporal and intl402 well
+    # github action windows runner only have 2 CPUs. that's why I disable Atomics(timeout occured with some tests)
+    - name: Run test262
+      run: |
+        set GC_FREE_SPACE_DIVISOR=1
+        pip install chardet
+        python tools\run-tests.py --engine=%cd%\out\escargot.exe test262 --extra-arg="--skip Temporal --skip intl402 --skip Atomics"
+      shell: cmd
+    - name: Run octane
+      run: |
+        copy test\octane\*.js
+        dir
+        .\out\escargot.exe run.js
+    - if: ${{ failure() }}
+      uses: mxschmitt/action-tmate@v3
+      timeout-minutes: 15
 
   test-on-windows-x86-x64:
     runs-on: windows-2022
diff --git a/build/target.cmake b/build/target.cmake
index bd6cc080b..9319b6b42 100644
--- a/build/target.cmake
+++ b/build/target.cmake
@@ -10,8 +10,23 @@ SET (ESCARGOT_BUILD_32BIT OFF)
 SET (ESCARGOT_BUILD_64BIT OFF)
 SET (ESCARGOT_BUILD_64BIT_LARGE OFF)
 
+# clang-cl defines ${CMAKE_CXX_COMPILER_ID} "Clang" and ${CMAKE_CXX_COMPILER_FRONTEND_VARIANT} "MSVC"
+SET (COMPILER_CLANG_CL OFF)
+IF (${CMAKE_VERSION} VERSION_GREATER "3.14.0")
+    IF (${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang" AND ${CMAKE_CXX_COMPILER_FRONTEND_VARIANT} STREQUAL "MSVC")
+        SET (COMPILER_CLANG_CL ON)
+    ENDIF()
+ENDIF()
+
 # Default options per compiler
-IF (${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU")
+IF (${CMAKE_CXX_COMPILER_ID} STREQUAL "MSVC" OR ${COMPILER_CLANG_CL})
+    SET (ESCARGOT_CXXFLAGS /std:c++17 /fp:strict /Zc:__cplusplus /EHs /source-charset:utf-8 /D_CRT_SECURE_NO_WARNINGS /DGC_NOT_DLL /wd4244 /wd4267 /wd4805 /wd4018 /wd4172)
+    SET (ESCARGOT_CXXFLAGS_RELEASE /O2 /Oy-)
+    SET (ESCARGOT_THIRDPARTY_CFLAGS /D_CRT_SECURE_NO_WARNINGS /DGC_NOT_DLL /Oy- /wd4146)
+    IF (${COMPILER_CLANG_CL})
+        SET (ESCARGOT_CXXFLAGS ${ESCARGOT_CXXFLAGS} /EHs -Wno-invalid-offsetof -Wno-inline-new-delete -fintegrated-cc1)
+    ENDIF()
+ELSEIF (${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU")
     SET (ESCARGOT_CXXFLAGS
         ${ESCARGOT_CXXFLAGS}
         -std=c++11 -g3
@@ -50,11 +65,6 @@ ELSEIF (${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang")
     SET (ESCARGOT_CXXFLAGS_DEBUG -O0 -Wall -Wextra -Werror)
     SET (ESCARGOT_CXXFLAGS_RELEASE -O2 -fno-stack-protector -fno-omit-frame-pointer)
     SET (ESCARGOT_THIRDPARTY_CFLAGS -w -g3 -fdata-sections -ffunction-sections -fno-omit-frame-pointer -fvisibility=hidden)
-ELSEIF (${CMAKE_CXX_COMPILER_ID} STREQUAL "MSVC")
-    SET (CMAKE_CXX_STANDARD 11)
-    SET (ESCARGOT_CXXFLAGS /fp:strict /Zc:__cplusplus /source-charset:utf-8 /D_CRT_SECURE_NO_WARNINGS /DGC_NOT_DLL /wd4244 /wd4267 /wd4805 /wd4018 /wd4172)
-    SET (ESCARGOT_CXXFLAGS_RELEASE /O2 /Oy-)
-    SET (ESCARGOT_THIRDPARTY_CFLAGS /D_CRT_SECURE_NO_WARNINGS /DGC_NOT_DLL /Oy- /wd4146)
 ELSE()
     MESSAGE (FATAL_ERROR ${CMAKE_CXX_COMPILER_ID} " is Unsupported Compiler")
 ENDIF()
diff --git a/src/Escargot.h b/src/Escargot.h
index dbea89d52..7d9202887 100755
--- a/src/Escargot.h
+++ b/src/Escargot.h
@@ -52,6 +52,10 @@
 
 #if defined(__clang__)
 #define COMPILER_CLANG 1
+// clang-cl defines _MSC_VER and __clang__ both
+#if defined(_MSC_VER)
+#define COMPILER_CLANG_CL 1
+#endif
 #elif defined(_MSC_VER)
 #define COMPILER_MSVC 1
 #elif (__GNUC__)
@@ -158,11 +162,6 @@
 #endif
 #endif
 
-#if defined(COMPILER_MSVC)
-#define strncasecmp _strnicmp
-#define strcasecmp _stricmp
-#endif
-
 #ifndef ATTRIBUTE_NO_SANITIZE_ADDRESS
 #if defined(COMPILER_GCC) || defined(COMPILER_CLANG)
 #define ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
@@ -217,6 +216,12 @@
 #define NOMINMAX
 #endif
 
+#if defined(OS_WINDOWS)
+#define strncasecmp _strnicmp
+#define strcasecmp _stricmp
+#endif
+
+
 /*
 we need to mark enum as unsigned if needs.
 because processing enum in msvc is little different
@@ -226,7 +231,7 @@ struct Foo { Type type: 1; };
 Foo f; f.type = 1;
 if (f.type == Type::B) { puts("failed in msvc."); }
 */
-#if defined(COMPILER_MSVC)
+#if defined(OS_WINDOWS)
 #define ENSURE_ENUM_UNSIGNED : unsigned int
 #else
 #define ENSURE_ENUM_UNSIGNED
@@ -481,7 +486,7 @@ void customEscargotErrorLogger(const char* format, ...);
 #if defined(COMPILER_GCC) || defined(COMPILER_CLANG)
 #define ESCARGOT_COMPUTED_GOTO_INTERPRETER
 // some devices cannot support getting label address from outside well
-#if (defined(CPU_ARM64) || (defined(CPU_ARM32) && defined(COMPILER_CLANG))) || defined(OS_DARWIN) || defined(OS_ANDROID)
+#if (defined(CPU_ARM64) || (defined(CPU_ARM32) && defined(COMPILER_CLANG))) || defined(OS_DARWIN) || defined(OS_ANDROID) || defined(OS_WINDOWS)
 #define ESCARGOT_COMPUTED_GOTO_INTERPRETER_INIT_WITH_NULL
 #endif
 #endif
diff --git a/src/api/EscargotPublic.cpp b/src/api/EscargotPublic.cpp
index 09912b1fc..c57f41057 100644
--- a/src/api/EscargotPublic.cpp
+++ b/src/api/EscargotPublic.cpp
@@ -205,20 +205,24 @@ class PlatformBridge : public Platform {
     PlatformRef* m_platform;
 };
 
-void PlatformRef::notifyHostImportModuleDynamicallyResult(ContextRef* relatedContext, ScriptRef* referrer, StringRef* src, PromiseObjectRef* promise, LoadModuleResult loadModuleResult)
+// making this function with lambda causes "cannot compile this forwarded non-trivially copyable parameter yet" on Windows/ClangCL
+static ValueRef* notifyHostImportModuleDynamicallyInnerExecute(ExecutionStateRef* state, PlatformRef::LoadModuleResult loadModuleResult, Script::ModuleData::ModulePromiseObject* promise)
 {
-    auto result = Evaluator::execute(relatedContext, [](ExecutionStateRef* state, LoadModuleResult loadModuleResult, Script::ModuleData::ModulePromiseObject* promise) -> ValueRef* {
-        if (loadModuleResult.script) {
-            if (loadModuleResult.script.value()->isExecuted()) {
-                if (loadModuleResult.script.value()->wasThereErrorOnModuleEvaluation()) {
-                    state->throwException(loadModuleResult.script.value()->moduleEvaluationError());
-                }
+    if (loadModuleResult.script) {
+        if (loadModuleResult.script.value()->isExecuted()) {
+            if (loadModuleResult.script.value()->wasThereErrorOnModuleEvaluation()) {
+                state->throwException(loadModuleResult.script.value()->moduleEvaluationError());
             }
-        } else {
-            state->throwException(ErrorObjectRef::create(state, loadModuleResult.errorCode, loadModuleResult.errorMessage));
         }
-        return ValueRef::createUndefined();
-    },
+    } else {
+        state->throwException(ErrorObjectRef::create(state, loadModuleResult.errorCode, loadModuleResult.errorMessage));
+    }
+    return ValueRef::createUndefined();
+}
+
+void PlatformRef::notifyHostImportModuleDynamicallyResult(ContextRef* relatedContext, ScriptRef* referrer, StringRef* src, PromiseObjectRef* promise, LoadModuleResult loadModuleResult)
+{
+    auto result = Evaluator::execute(relatedContext, notifyHostImportModuleDynamicallyInnerExecute,
                                      loadModuleResult, (Script::ModuleData::ModulePromiseObject*)promise);
 
     Script::ModuleData::ModulePromiseObject* mp = (Script::ModuleData::ModulePromiseObject*)promise;
diff --git a/src/interpreter/ByteCode.h b/src/interpreter/ByteCode.h
index 05c80409f..8f8bb854f 100644
--- a/src/interpreter/ByteCode.h
+++ b/src/interpreter/ByteCode.h
@@ -197,7 +197,7 @@ struct ByteCodeLOC {
     }
 };
 
-#if defined(NDEBUG) && defined(ESCARGOT_32) && !defined(COMPILER_MSVC)
+#if defined(NDEBUG) && defined(ESCARGOT_32) && !defined(OS_WINDOWS)
 #define BYTECODE_SIZE_CHECK_IN_32BIT(codeName, size) COMPILE_ASSERT(sizeof(codeName) == size, "");
 #else
 #define BYTECODE_SIZE_CHECK_IN_32BIT(CodeName, Size)
@@ -1247,7 +1247,7 @@ class GetObjectPreComputedCase : public ByteCode {
 
     static constexpr size_t inlineCacheProtoTraverseMaxCount = 12;
 
-    enum GetInlineCacheMode {
+    enum GetInlineCacheMode ENSURE_ENUM_UNSIGNED {
         None,
         Simple,
         Complex
diff --git a/src/interpreter/ByteCodeInterpreter.cpp b/src/interpreter/ByteCodeInterpreter.cpp
index 3d3900ba5..e3dc82d86 100644
--- a/src/interpreter/ByteCodeInterpreter.cpp
+++ b/src/interpreter/ByteCodeInterpreter.cpp
@@ -51,7 +51,7 @@
 #include "parser/ScriptParser.h"
 #include "CheckedArithmetic.h"
 
-#if defined(ESCARGOT_COMPUTED_GOTO_INTERPRETER)
+#if defined(ESCARGOT_COMPUTED_GOTO_INTERPRETER) && !defined(ESCARGOT_COMPUTED_GOTO_INTERPRETER_INIT_WITH_NULL)
 extern char FillOpcodeTableAsmLbl[];
 const void* FillOpcodeTableAddress[] = { &FillOpcodeTableAsmLbl[0] };
 #endif
@@ -1654,7 +1654,11 @@ Value Interpreter::interpret(ExecutionState* state, ByteCodeBlock* byteCodeBlock
             __attribute__((cold));
 #endif
 #if defined(ESCARGOT_COMPUTED_GOTO_INTERPRETER)
+
+#if !defined(ESCARGOT_COMPUTED_GOTO_INTERPRETER_INIT_WITH_NULL)
             asm volatile("FillOpcodeTableAsmLbl:");
+#endif
+
 #if defined(ENABLE_CODE_CACHE)
 #define REGISTER_TABLE(opcode)                                          \
     g_opcodeTable.m_addressTable[opcode##Opcode] = &&opcode##OpcodeLbl; \
diff --git a/src/runtime/BigInt.cpp b/src/runtime/BigInt.cpp
index eaf3533ff..882c87dde 100644
--- a/src/runtime/BigInt.cpp
+++ b/src/runtime/BigInt.cpp
@@ -472,7 +472,7 @@ BigInt* BigInt::leftShift(ExecutionState& state, BigInt* src) const
     bf_init(ThreadLocal::bfContext(), &r);
 
     slimb_t v2;
-#if defined(ESCARGOT_32) || defined(COMPILER_MSVC)
+#if defined(ESCARGOT_32) || defined(OS_WINDOWS)
     bf_get_int32(&v2, src->bf(), 0);
     if (v2 == std::numeric_limits<int32_t>::min()) {
         v2 = std::numeric_limits<int32_t>::min() + 1;
@@ -502,7 +502,7 @@ BigInt* BigInt::rightShift(ExecutionState& state, BigInt* src) const
     bf_init(ThreadLocal::bfContext(), &r);
 
     slimb_t v2;
-#if defined(ESCARGOT_32) || defined(COMPILER_MSVC)
+#if defined(ESCARGOT_32) || defined(OS_WINDOWS)
     bf_get_int32(&v2, src->bf(), 0);
     if (v2 == std::numeric_limits<int32_t>::min()) {
         v2 = std::numeric_limits<int32_t>::min() + 1;
diff --git a/src/runtime/String.h b/src/runtime/String.h
index ada04828c..c95c9dcd0 100644
--- a/src/runtime/String.h
+++ b/src/runtime/String.h
@@ -596,7 +596,7 @@ class String : public PointerValue {
     }
 };
 
-#if defined(NDEBUG) && defined(ESCARGOT_32) && !defined(COMPILER_MSVC)
+#if defined(NDEBUG) && defined(ESCARGOT_32) && !defined(OS_WINDOWS)
 COMPILE_ASSERT(sizeof(String) == sizeof(size_t) * 4, "");
 #endif
 
diff --git a/src/runtime/ValueInlines.h b/src/runtime/ValueInlines.h
index a9f986050..1327533b6 100644
--- a/src/runtime/ValueInlines.h
+++ b/src/runtime/ValueInlines.h
@@ -751,7 +751,8 @@ inline bool Value::isCallable() const
 // https://www.ecma-international.org/ecma-262/6.0/#sec-tonumber
 inline double Value::toNumber(ExecutionState& state) const
 {
-#ifdef ESCARGOT_64
+// there is optimizer bug on clang-cl with below block
+#if defined(ESCARGOT_64) && !defined(COMPILER_CLANG_CL)
     auto n = u.asInt64 & TagTypeNumber;
     if (LIKELY(n)) {
         if (n == TagTypeNumber) {
diff --git a/src/shell/Shell.cpp b/src/shell/Shell.cpp
index b5e7463ba..ab6dd1b32 100644
--- a/src/shell/Shell.cpp
+++ b/src/shell/Shell.cpp
@@ -43,7 +43,7 @@
 #include <dlfcn.h>
 #endif
 
-#if !defined(__APPLE__) && !defined(_WINDOWS)
+#if !defined(__APPLE__) && !defined(_WINDOWS) && !defined(_WIN32) && !defined(_WIN64)
 #include <signal.h>
 #include <execinfo.h>
 
@@ -873,6 +873,11 @@ static bool evalScript(ContextRef* context, StringRef* source, StringRef* srcNam
     return result;
 }
 
+// making this function with lambda causes "cannot compile this forwarded non-trivially copyable parameter yet" on Windows/ClangCL
+static void globalObjectProxyCallback(ExecutionStateRef* state, GlobalObjectProxyObjectRef* proxy, GlobalObjectRef* targetGlobalObject, GlobalObjectProxyObjectRef::AccessOperationType operationType, OptionalRef<AtomicStringRef> nonIndexedStringPropertyNameIfExists)
+{
+    // TODO check security
+}
 
 PersistentRefHolder<ContextRef> createEscargotContext(VMInstanceRef* instance, bool isMainThread)
 {
@@ -881,12 +886,9 @@ PersistentRefHolder<ContextRef> createEscargotContext(VMInstanceRef* instance, b
     Evaluator::execute(context, [](ExecutionStateRef* state, bool isMainThread) -> ValueRef* {
         ContextRef* context = state->context();
 
-        GlobalObjectProxyObjectRef* proxy = GlobalObjectProxyObjectRef::create(state, state->context()->globalObject(), [](ExecutionStateRef* state, GlobalObjectProxyObjectRef* proxy, GlobalObjectRef* targetGlobalObject, GlobalObjectProxyObjectRef::AccessOperationType operationType, OptionalRef<AtomicStringRef> nonIndexedStringPropertyNameIfExists) {
-            // TODO check security
-        });
+        GlobalObjectProxyObjectRef* proxy = GlobalObjectProxyObjectRef::create(state, state->context()->globalObject(), globalObjectProxyCallback);
         context->setGlobalObjectProxy(proxy);
 
-
         {
             FunctionObjectRef::NativeFunctionInfo nativeFunctionInfo(AtomicStringRef::create(context, "print"), builtinPrint, 1, true, false);
             FunctionObjectRef* buildFunctionObjectRef = FunctionObjectRef::create(state, nativeFunctionInfo);
@@ -1056,13 +1058,13 @@ PersistentRefHolder<ContextRef> createEscargotContext(VMInstanceRef* instance, b
     return context;
 }
 
-#if defined(_WINDOWS)
+#if defined(_WINDOWS) || defined(_WIN32) || defined(_WIN64)
 #include <windows.h> // for SetConsoleOutputCP
 #endif
 
 int main(int argc, char* argv[])
 {
-#if defined(_WINDOWS)
+#if defined(_WINDOWS) || defined(_WIN32) || defined(_WIN64)
     SetConsoleOutputCP(65001);
 #endif
 #ifndef NDEBUG
@@ -1070,7 +1072,7 @@ int main(int argc, char* argv[])
     setbuf(stderr, NULL);
 #endif
 
-#if defined(ESCARGOT_ENABLE_TEST) && !defined(__APPLE__) && !defined(_WINDOWS)
+#if defined(ESCARGOT_ENABLE_TEST) && !defined(__APPLE__) && !defined(_WINDOWS) && !defined(_WIN32) && !defined(_WIN64)
     struct sigaction sa;
     sa.sa_handler = (void (*)(int))btSighandler;
     sigemptyset(&sa.sa_mask);
diff --git a/src/util/Util.cpp b/src/util/Util.cpp
index 1dd46f277..4c21bacb9 100644
--- a/src/util/Util.cpp
+++ b/src/util/Util.cpp
@@ -43,9 +43,9 @@
 #include "Vector.h"
 #include "Util.h"
 
-#if defined(__ANDROID__)
+#if defined(OS_ANDROID)
 #include <sys/time.h>
-#elif defined(_WINDOWS)
+#elif defined(OS_WINDOWS)
 #include <time.h>
 #else
 #include <sys/timeb.h>
diff --git a/third_party/GCutil b/third_party/GCutil
index c655a366e..65dffa8cf 160000
--- a/third_party/GCutil
+++ b/third_party/GCutil
@@ -1 +1 @@
-Subproject commit c655a366ee4f03d60f80f76782e35690c5fb0385
+Subproject commit 65dffa8cf5832ba6f28e2ab617e9c4b69467ae32
diff --git a/third_party/libbf/cutils.h b/third_party/libbf/cutils.h
index 653588a2d..8225207b5 100644
--- a/third_party/libbf/cutils.h
+++ b/third_party/libbf/cutils.h
@@ -119,7 +119,7 @@ static inline int64_t min_int64(int64_t a, int64_t b)
         return b;
 }
 
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(__clang__)
 #include <intrin.h>
 static inline int __builtin_ctz(unsigned x)
 {