diff -ruN llvm-orig/llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/SwapByteOrder.h llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/SwapByteOrder.h
--- llvm-orig/llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/SwapByteOrder.h	2021-04-06 19:38:18.000000000 +0300
+++ llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/SwapByteOrder.h	2021-06-09 16:00:20.111549941 +0300
@@ -22,7 +22,7 @@
 #endif
 
 #if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__) ||            \
-    defined(__Fuchsia__) || defined(__EMSCRIPTEN__)
+    defined(__Fuchsia__) || defined(__EMSCRIPTEN__) || defined(__serenity__)
 #include <endian.h>
 #elif defined(_AIX)
 #include <sys/machine.h>
diff -ruN llvm-orig/llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/ConvertUTF.h llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/ConvertUTF.h
--- llvm-orig/llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/ConvertUTF.h	2021-04-06 19:38:18.000000000 +0300
+++ llvm-project-llvmorg-12.0.0/llvm/include/llvm/Support/ConvertUTF.h	2021-06-09 16:04:10.069288846 +0300
@@ -200,19 +200,19 @@
 * Converts a UTF-8 StringRef to a std::wstring.
 * \return true on success.
 */
-bool ConvertUTF8toWide(llvm::StringRef Source, std::wstring &Result);
+bool ConvertUTF8toWide(llvm::StringRef Source, std::string &Result);
 
 /**
 * Converts a UTF-8 C-string to a std::wstring.
 * \return true on success.
 */
-bool ConvertUTF8toWide(const char *Source, std::wstring &Result);
+bool ConvertUTF8toWide(const char *Source, std::string &Result);
 
 /**
 * Converts a std::wstring to a UTF-8 encoded std::string.
 * \return true on success.
 */
-bool convertWideToUTF8(const std::wstring &Source, std::string &Result);
+bool convertWideToUTF8(const std::string &Source, std::string &Result);
 
 
 /**
diff -ruN llvm-orig/llvm-project-llvmorg-12.0.0/llvm/lib/Support/ConvertUTFWrapper.cpp llvm-project-llvmorg-12.0.0/llvm/lib/Support/ConvertUTFWrapper.cpp
--- llvm-orig/llvm-project-llvmorg-12.0.0/llvm/lib/Support/ConvertUTFWrapper.cpp	2021-04-06 19:38:18.000000000 +0300
+++ llvm-project-llvmorg-12.0.0/llvm/lib/Support/ConvertUTFWrapper.cpp	2021-06-09 16:15:53.330400711 +0300
@@ -196,15 +196,15 @@
     Result.clear();
     return false;
   }
-  Result.resize(reinterpret_cast<wchar_t *>(ResultPtr) - &Result[0]);
+  Result.resize(reinterpret_cast<char *>(ResultPtr) - &Result[0]);
   return true;
 }
 
-bool ConvertUTF8toWide(llvm::StringRef Source, std::wstring &Result) {
+bool ConvertUTF8toWide(llvm::StringRef Source, std::string &Result) {
   return ConvertUTF8toWideInternal(Source, Result);
 }
 
-bool ConvertUTF8toWide(const char *Source, std::wstring &Result) {
+bool ConvertUTF8toWide(const char *Source, std::string &Result) {
   if (!Source) {
     Result.clear();
     return true;
@@ -212,7 +212,7 @@
   return ConvertUTF8toWide(llvm::StringRef(Source), Result);
 }
 
-bool convertWideToUTF8(const std::wstring &Source, std::string &Result) {
+bool convertWideToUTF8(const std::string &Source, std::string &Result) {
   if (sizeof(wchar_t) == 1) {
     const UTF8 *Start = reinterpret_cast<const UTF8 *>(Source.data());
     const UTF8 *End =