diff --git a/Source/JavaScriptCore/generator/Argument.rb b/Source/JavaScriptCore/generator/Argument.rb
index fdf4e97519b69..dd93c0d9e35e1 100644
--- a/Source/JavaScriptCore/generator/Argument.rb
+++ b/Source/JavaScriptCore/generator/Argument.rb
@@ -84,7 +84,7 @@ def setter(traits)
     {
         if (!#{Fits::check "size", "value", @type})
             value = func();
-        auto* stream = std::bit_cast<typename TypeBySize<size>::unsignedType*>(reinterpret_cast<uint8_t*>(this) + #{@index} * size + PaddingBySize<size>::value + OpcodeIDWidthBySize<#{traits}, size>::opcodeIDSize);
+        auto* stream = __bit_cast<typename TypeBySize<size>::unsignedType*>(reinterpret_cast<uint8_t*>(this) + #{@index} * size + PaddingBySize<size>::value + OpcodeIDWidthBySize<#{traits}, size>::opcodeIDSize);
         *stream = #{Fits::convert "size", "value", @type};
     }
 EOF
diff --git a/Source/JavaScriptCore/generator/Opcode.rb b/Source/JavaScriptCore/generator/Opcode.rb
index ce42dc2b81a8f..e2e15ed5f99b0 100644
--- a/Source/JavaScriptCore/generator/Opcode.rb
+++ b/Source/JavaScriptCore/generator/Opcode.rb
@@ -290,29 +290,29 @@ def constructors
     #{capitalized_name}(const uint8_t* stream)
         #{init.call("OpcodeSize::Narrow")}
     {
-        ASSERT_UNUSED(stream, static_cast<#{opcodeIDType}>(std::bit_cast<const typename OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Narrow>::opcodeType*>(stream)[-1]) == opcodeID);
+        ASSERT_UNUSED(stream, static_cast<#{opcodeIDType}>(__bit_cast<const typename OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Narrow>::opcodeType*>(stream)[-1]) == opcodeID);
     }
 
     #{capitalized_name}(const uint16_t* stream)
         #{init.call("OpcodeSize::Wide16")}
     {
-        ASSERT_UNUSED(stream, static_cast<#{opcodeIDType}>(std::bit_cast<const typename OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide16>::opcodeType*>(stream)[-1]) == opcodeID);
+        ASSERT_UNUSED(stream, static_cast<#{opcodeIDType}>(__bit_cast<const typename OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide16>::opcodeType*>(stream)[-1]) == opcodeID);
     }
 
 
     #{capitalized_name}(const uint32_t* stream)
         #{init.call("OpcodeSize::Wide32")}
     {
-        ASSERT_UNUSED(stream, static_cast<#{opcodeIDType}>(std::bit_cast<const typename OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide32>::opcodeType*>(stream)[-1]) == opcodeID);
+        ASSERT_UNUSED(stream, static_cast<#{opcodeIDType}>(__bit_cast<const typename OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide32>::opcodeType*>(stream)[-1]) == opcodeID);
     }
 
     static #{capitalized_name} decode(const uint8_t* stream)
     {
         // A pointer is pointing to the first operand (opcode and prefix are not included).
         if (*stream == #{wide32})
-            return { std::bit_cast<const uint32_t*>(stream + /* prefix */ 1 + OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide32>::opcodeIDSize) };
+            return { __bit_cast<const uint32_t*>(stream + /* prefix */ 1 + OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide32>::opcodeIDSize) };
         if (*stream == #{wide16})
-            return { std::bit_cast<const uint16_t*>(stream + /* prefix */ 1 + OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide16>::opcodeIDSize) };
+            return { __bit_cast<const uint16_t*>(stream + /* prefix */ 1 + OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Wide16>::opcodeIDSize) };
         return { stream + OpcodeIDWidthBySize<#{type_prefix}OpcodeTraits, OpcodeSize::Narrow>::opcodeIDSize };
     }
 EOF