diff --git a/system/lib/libcxxabi/src/cxa_exception.cpp b/system/lib/libcxxabi/src/cxa_exception.cpp
index 4b82d0bf066ee..33e5a4d7d4dbf 100644
--- a/system/lib/libcxxabi/src/cxa_exception.cpp
+++ b/system/lib/libcxxabi/src/cxa_exception.cpp
@@ -272,7 +272,7 @@ will call terminate, assuming that there was no handler for the
 exception.
 */
 
-#if defined(__EMSCRIPTEN__) && defined(__WASM_EXCEPTIONS__) && !defined(NDEBUG)
+#if defined(__EMSCRIPTEN__) && defined(__wasm_exception_handling__) && !defined(NDEBUG)
 extern "C" {
 void __throw_exception_with_stack_trace(_Unwind_Exception*);
 } // extern "C"
@@ -298,7 +298,7 @@ __cxa_throw(void *thrown_object, std::type_info *tinfo, void (_LIBCXXABI_DTOR_FU
 
 #ifdef __USING_SJLJ_EXCEPTIONS__
     _Unwind_SjLj_RaiseException(&exception_header->unwindHeader);
-#elif defined(__EMSCRIPTEN__) && defined(__WASM_EXCEPTIONS__) && !defined(NDEBUG)
+#elif defined(__EMSCRIPTEN__) && defined(__wasm_exception_handling__) && !defined(NDEBUG)
     // In debug mode, call a JS library function to use WebAssembly.Exception JS
     // API, which enables us to include stack traces
     __throw_exception_with_stack_trace(&exception_header->unwindHeader);
@@ -656,7 +656,7 @@ void __cxa_rethrow() {
     }
 #ifdef __USING_SJLJ_EXCEPTIONS__
     _Unwind_SjLj_RaiseException(&exception_header->unwindHeader);
-#elif defined(__EMSCRIPTEN__) && defined(__WASM_EXCEPTIONS__) && !defined(NDEBUG)
+#elif defined(__EMSCRIPTEN__) && defined(__wasm_exception_handling__) && !defined(NDEBUG)
     // In debug mode, call a JS library function to use WebAssembly.Exception JS
     // API, which enables us to include stack traces
     __throw_exception_with_stack_trace(&exception_header->unwindHeader);
@@ -785,7 +785,7 @@ __cxa_rethrow_primary_exception(void* thrown_object)
         dep_exception_header->unwindHeader.exception_cleanup = dependent_exception_cleanup;
 #ifdef __USING_SJLJ_EXCEPTIONS__
         _Unwind_SjLj_RaiseException(&dep_exception_header->unwindHeader);
-#elif defined(__EMSCRIPTEN__) && defined(__WASM_EXCEPTIONS__) && !defined(NDEBUG)
+#elif defined(__EMSCRIPTEN__) && defined(__wasm_exception_handling__) && !defined(NDEBUG)
         // In debug mode, call a JS library function to use
         // WebAssembly.Exception JS API, which enables us to include stack
         // traces
diff --git a/system/lib/libcxxabi/src/cxa_exception_emscripten.cpp b/system/lib/libcxxabi/src/cxa_exception_emscripten.cpp
index 20a3ba56816c0..b9b9feaf9ff61 100644
--- a/system/lib/libcxxabi/src/cxa_exception_emscripten.cpp
+++ b/system/lib/libcxxabi/src/cxa_exception_emscripten.cpp
@@ -21,7 +21,7 @@
 #include "stdio.h"
 #include "assert.h"
 
-#ifdef __WASM_EXCEPTIONS__
+#ifdef __wasm_exception_handling__
 #error "This file should only be included when building with emscripten exceptions"
 #endif
 
diff --git a/system/lib/libcxxabi/src/cxa_exception_js_utils.cpp b/system/lib/libcxxabi/src/cxa_exception_js_utils.cpp
index 05d908d45577d..c4227c24ba740 100644
--- a/system/lib/libcxxabi/src/cxa_exception_js_utils.cpp
+++ b/system/lib/libcxxabi/src/cxa_exception_js_utils.cpp
@@ -39,7 +39,7 @@ static inline __cxa_exception* cxa_exception_from_unwind_exception(
   return cxa_exception_from_thrown_object(unwind_exception + 1);
 }
 
-#ifdef __WASM_EXCEPTIONS__
+#ifdef __wasm_exception_handling__
 struct __cxa_dependent_exception;
 uint64_t __getExceptionClass(const _Unwind_Exception* unwind_exception);
 static bool isDependentException(_Unwind_Exception* unwind_exception) {
@@ -87,7 +87,7 @@ void __get_exception_message(void* thrown_object, char** type, char** message) {
     static_cast<const __shim_type_info*>(&typeid(std::exception));
   int can_catch = catch_type->can_catch(thrown_type, thrown_object);
   if (can_catch) {
-#if __WASM_EXCEPTIONS__
+#if __wasm_exception_handling__
     if (isDependentException(&exception_header->unwindHeader)) {
       thrown_object =
         reinterpret_cast<__cxa_dependent_exception*>(exception_header)
diff --git a/system/lib/libcxxabi/src/cxa_personality.cpp b/system/lib/libcxxabi/src/cxa_personality.cpp
index 1dc47b6d8bc1b..e1321e3fff916 100644
--- a/system/lib/libcxxabi/src/cxa_personality.cpp
+++ b/system/lib/libcxxabi/src/cxa_personality.cpp
@@ -70,7 +70,7 @@ extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD,
 +------------------+--+-----+-----+------------------------+--------------------------+
 | callSiteTableLength | (ULEB128) | Call Site Table length, used to find Action table |
 +---------------------+-----------+---------------------------------------------------+
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__wasm_exception_handling__)
 +---------------------+-----------+------------------------------------------------+
 | Beginning of Call Site Table            The current ip lies within the           |
 | ...                                     (start, length) range of one of these    |
@@ -84,7 +84,7 @@ extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD,
 | +-------------+---------------------------------+------------------------------+ |
 | ...                                                                              |
 +----------------------------------------------------------------------------------+
-#else  // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
+#else  // __USING_SJLJ_EXCEPTIONS__ || __wasm_exception_handling__
 +---------------------+-----------+------------------------------------------------+
 | Beginning of Call Site Table            The current ip is a 1-based index into   |
 | ...                                     this table.  Or it is -1 meaning no      |
@@ -97,7 +97,7 @@ extern "C" EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD,
 | +-------------+---------------------------------+------------------------------+ |
 | ...                                                                              |
 +----------------------------------------------------------------------------------+
-#endif // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
+#endif // __USING_SJLJ_EXCEPTIONS__ || __wasm_exception_handling__
 +---------------------------------------------------------------------+
 | Beginning of Action Table       ttypeIndex == 0 : cleanup           |
 | ...                             ttypeIndex  > 0 : catch             |
@@ -547,7 +547,7 @@ void
 set_registers(_Unwind_Exception* unwind_exception, _Unwind_Context* context,
               const scan_results& results)
 {
-#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__WASM_EXCEPTIONS__)
+#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__wasm_exception_handling__)
 #define __builtin_eh_return_data_regno(regno) regno
 #elif defined(__ibmxl__)
 // IBM xlclang++ compiler does not support __builtin_eh_return_data_regno.
@@ -642,7 +642,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     // Get beginning current frame's code (as defined by the
     // emitted dwarf code)
     uintptr_t funcStart = _Unwind_GetRegionStart(context);
-#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__WASM_EXCEPTIONS__)
+#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__wasm_exception_handling__)
     if (ip == uintptr_t(-1))
     {
         // no action
@@ -652,9 +652,9 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     else if (ip == 0)
         call_terminate(native_exception, unwind_exception);
     // ip is 1-based index into call site table
-#else  // !__USING_SJLJ_EXCEPTIONS__ && !__WASM_EXCEPTIONS__
+#else  // !__USING_SJLJ_EXCEPTIONS__ && !__wasm_exception_handling__
     uintptr_t ipOffset = ip - funcStart;
-#endif // !__USING_SJLJ_EXCEPTIONS__ && !__WASM_EXCEPTIONS__
+#endif // !__USING_SJLJ_EXCEPTIONS__ && !__wasm_exception_handling__
     const uint8_t* classInfo = NULL;
     // Note: See JITDwarfEmitter::EmitExceptionTable(...) for corresponding
     //       dwarf emission
@@ -676,7 +676,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     // Walk call-site table looking for range that
     // includes current PC.
     uint8_t callSiteEncoding = *lsda++;
-#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__WASM_EXCEPTIONS__)
+#if defined(__USING_SJLJ_EXCEPTIONS__) || defined(__wasm_exception_handling__)
     (void)callSiteEncoding;  // Unused when using SjLj/Wasm exceptions
 #endif
     uint32_t callSiteTableLength = static_cast<uint32_t>(readULEB128(&lsda));
@@ -687,7 +687,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
     while (callSitePtr < callSiteTableEnd)
     {
         // There is one entry per call site.
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__wasm_exception_handling__)
         // The call sites are non-overlapping in [start, start+length)
         // The call sites are ordered in increasing value of start
         uintptr_t start = readEncodedPointer(&callSitePtr, callSiteEncoding);
@@ -695,15 +695,15 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
         uintptr_t landingPad = readEncodedPointer(&callSitePtr, callSiteEncoding);
         uintptr_t actionEntry = readULEB128(&callSitePtr);
         if ((start <= ipOffset) && (ipOffset < (start + length)))
-#else  // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
+#else  // __USING_SJLJ_EXCEPTIONS__ || __wasm_exception_handling__
         // ip is 1-based index into this table
         uintptr_t landingPad = readULEB128(&callSitePtr);
         uintptr_t actionEntry = readULEB128(&callSitePtr);
         if (--ip == 0)
-#endif // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
+#endif // __USING_SJLJ_EXCEPTIONS__ || __wasm_exception_handling__
         {
             // Found the call site containing ip.
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__wasm_exception_handling__)
             if (landingPad == 0)
             {
                 // No handler here
@@ -711,9 +711,9 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
                 return;
             }
             landingPad = (uintptr_t)lpStart + landingPad;
-#else  // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
+#else  // __USING_SJLJ_EXCEPTIONS__ || __wasm_exception_handling__
             ++landingPad;
-#endif // __USING_SJLJ_EXCEPTIONS__ || __WASM_EXCEPTIONS__
+#endif // __USING_SJLJ_EXCEPTIONS__ || __wasm_exception_handling__
             results.landingPad = landingPad;
             if (actionEntry == 0)
             {
@@ -839,7 +839,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
                 action += actionOffset;
             }  // there is no break out of this loop, only return
         }
-#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__WASM_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__wasm_exception_handling__)
         else if (ipOffset < start)
         {
             // There is no call site for this ip
@@ -847,7 +847,7 @@ static void scan_eh_tab(scan_results &results, _Unwind_Action actions,
             // Possible stack corruption.
             call_terminate(native_exception, unwind_exception);
         }
-#endif // !__USING_SJLJ_EXCEPTIONS__ && !__WASM_EXCEPTIONS__
+#endif // !__USING_SJLJ_EXCEPTIONS__ && !__wasm_exception_handling__
     }  // there might be some tricky cases which break out of this loop
 
     // It is possible that no eh table entry specify how to handle
@@ -904,7 +904,7 @@ _UA_CLEANUP_PHASE
 */
 
 #if !defined(_LIBCXXABI_ARM_EHABI)
-#ifdef __WASM_EXCEPTIONS__
+#ifdef __wasm_exception_handling__
 _Unwind_Reason_Code __gxx_personality_wasm0
 #elif defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
 static _Unwind_Reason_Code __gxx_personality_imp
@@ -973,7 +973,7 @@ __gxx_personality_v0
             exc->languageSpecificData = results.languageSpecificData;
             exc->catchTemp = reinterpret_cast<void*>(results.landingPad);
             exc->adjustedPtr = results.adjustedPtr;
-#ifdef __WASM_EXCEPTIONS__
+#ifdef __wasm_exception_handling__
             // Wasm only uses a single phase (_UA_SEARCH_PHASE), so save the
             // results here.
             set_registers(unwind_exception, context, results);
diff --git a/system/lib/libcxxabi/src/private_typeinfo.cpp b/system/lib/libcxxabi/src/private_typeinfo.cpp
index 750375e5c5e00..06cd70c110960 100644
--- a/system/lib/libcxxabi/src/private_typeinfo.cpp
+++ b/system/lib/libcxxabi/src/private_typeinfo.cpp
@@ -1547,7 +1547,7 @@ __base_class_type_info::search_below_dst(__dynamic_cast_info* info,
 
 
 // XXX EMSCRIPTEN
-#if defined(__wasm__) && !defined(__WASM_EXCEPTIONS__)
+#if defined(__wasm__) && !defined(__wasm_exception_handling__)
 
 #include "cxa_exception.h"
 
@@ -1602,5 +1602,4 @@ void *__cxa_get_exception_ptr(void *thrown_object) throw() {
 
 }  // __cxxabiv1
 
-#endif // __wasm__ && !__WASM_EXCEPTIONS__
-
+#endif // __wasm__ && !__wasm_exception_handling__
diff --git a/system/lib/libunwind/src/Unwind-wasm.c b/system/lib/libunwind/src/Unwind-wasm.c
index b18b32c5d1784..b21348acc90e8 100644
--- a/system/lib/libunwind/src/Unwind-wasm.c
+++ b/system/lib/libunwind/src/Unwind-wasm.c
@@ -14,7 +14,7 @@
 
 #include "config.h"
 
-#ifdef __WASM_EXCEPTIONS__
+#ifdef __wasm_exception_handling__
 
 #include "unwind.h"
 #include <threads.h>
@@ -120,4 +120,4 @@ _Unwind_GetRegionStart(struct _Unwind_Context *context) {
   return 0;
 }
 
-#endif // defined(__WASM_EXCEPTIONS__)
+#endif // defined(__wasm_exception_handling__)
diff --git a/tools/system_libs.py b/tools/system_libs.py
index 1d88c31a29dfd..d17c049405147 100644
--- a/tools/system_libs.py
+++ b/tools/system_libs.py
@@ -1640,8 +1640,6 @@ def get_cflags(self):
       # The code used to interpret exceptions during terminate
       # is not compatible with emscripten exceptions.
       cflags.append('-DLIBCXXABI_SILENT_TERMINATE')
-    elif self.eh_mode == Exceptions.WASM_LEGACY:
-      cflags.append('-D__WASM_EXCEPTIONS__')
     return cflags
 
   def get_files(self):
@@ -1721,8 +1719,6 @@ class libcxx(ExceptionLibrary, MTLibrary, DebugLibrary):
 
   def get_cflags(self):
     cflags = super().get_cflags()
-    if self.eh_mode in (Exceptions.WASM_LEGACY, Exceptions.WASM):
-      cflags.append('-D__WASM_EXCEPTIONS__')
     return cflags
 
 
@@ -1755,8 +1751,6 @@ def get_cflags(self):
       cflags.append('-D_LIBUNWIND_HAS_NO_EXCEPTIONS')
     elif self.eh_mode == Exceptions.EMSCRIPTEN:
       cflags.append('-D__EMSCRIPTEN_EXCEPTIONS__')
-    elif self.eh_mode in (Exceptions.WASM_LEGACY, Exceptions.WASM):
-      cflags.append('-D__WASM_EXCEPTIONS__')
     return cflags