Based on https://github.com/cisco/openh264/pull/2877

--- codec/common/arm64/arm_arch64_common_macro.S.orig	2018-06-27 01:36:43 UTC
+++ codec/common/arm64/arm_arch64_common_macro.S
@@ -52,13 +52,17 @@ ret
 .align 2
 .global \funcName
 .type \funcName, %function
+#ifndef __clang__
 .func \funcName
+#endif
 \funcName:
 .endm
 
 .macro WELS_ASM_AARCH64_FUNC_END
 ret
+#ifndef __clang__
 .endfunc
+#endif
 .endm
 
 #endif
