diff --git a/lib/compiler-rt/builtins/int_lib.h b/lib/compiler-rt/builtins/int_lib.h
index 787777a..80a7c41 100644
--- a/lib/compiler-rt/builtins/int_lib.h
+++ b/lib/compiler-rt/builtins/int_lib.h
@@ -27,27 +27,28 @@
 
 #if defined(__ELF__)
 #define FNALIAS(alias_name, original_name) \
-  void alias_name() __attribute__((alias(#original_name)))
+  void alias_name() __attribute__((__alias__(#original_name)))
+#define COMPILER_RT_ALIAS(aliasee) __attribute__((__alias__(#aliasee)))
 #else
 #define FNALIAS(alias, name) _Pragma("GCC error(\"alias unsupported on this file format\")")
+#define COMPILER_RT_ALIAS(aliasee) _Pragma("GCC error(\"alias unsupported on this file format\")")
 #endif
 
 /* ABI macro definitions */
 
 #if __ARM_EABI__
-# define ARM_EABI_FNALIAS(aeabi_name, name)         \
-  void __aeabi_##aeabi_name() __attribute__((alias("__" #name)));
 # ifdef COMPILER_RT_ARMHF_TARGET
 #   define COMPILER_RT_ABI
 # else
-#   define COMPILER_RT_ABI __attribute__((pcs("aapcs")))
+#   define COMPILER_RT_ABI __attribute__((__pcs__("aapcs")))
 # endif
 #else
-# define ARM_EABI_FNALIAS(aeabi_name, name)
 # define COMPILER_RT_ABI
 #endif
 
-#ifdef _MSC_VER
+#define AEABI_RTABI __attribute__((__pcs__("aapcs")))
+
+#if defined(_MSC_VER) && !defined(__clang__)
 #define ALWAYS_INLINE __forceinline
 #define NOINLINE __declspec(noinline)
 #define NORETURN __declspec(noreturn)