Get rid of clang warnings for UC_INLINE

include/ucore/mbuf.h

@@ -4,11 +4,17 @@
 #include <stddef.h>
 #include "tailq.h"
 
+#ifndef UC_INLINE
 #ifdef __GNUC__
+#  ifdef __clang__
 #    define UC_INLINE inline __attribute__((always_inline))
 #  else
+#    define UC_INLINE inline __attribute__((always_inline,flatten))
+#  endif
+#else
 #  define UC_INLINE inline
 #endif
+#endif
 
 enum UC_MBUF_FLAGS {
     UC_MBUF_FL_MALLOC        = 0x0001, //MBuf and MBuf->bufstart are seperatly malloc'd

include/ucore/pack.h

@@ -2,11 +2,18 @@
 #define UC_PACK_H_
 
 #include <stdint.h>
+
+#ifndef UC_INLINE
 #ifdef __GNUC__
+#  ifdef __clang__
 #    define UC_INLINE inline __attribute__((always_inline))
 #  else
+#    define UC_INLINE inline __attribute__((always_inline,flatten))
+#  endif
+#else
 #  define UC_INLINE inline
 #endif
+#endif
 
 /** Functions for serializing/de-serializing integers to and from
  * byte arrays.

include/ucore/tailq.h

@@ -1,11 +1,17 @@
 #ifndef UC_TAILQ_H_
 #define UC_TAILQ_H_
 
+#ifndef UC_INLINE
 #ifdef __GNUC__
+#  ifdef __clang__
+#    define UC_INLINE inline __attribute__((always_inline))
+#  else
 #    define UC_INLINE inline __attribute__((always_inline,flatten))
+#  endif
 #else
 #  define UC_INLINE inline
 #endif
+#endif
 /**
  * Doubly Linked List.
  * It is used either as