av_alias is an attribute and belongs to attributes.h

also attributes.h is public and external api and can thus not depend
on configure tested compiler support thus this part is removed. A
different solution must be found if this breaks for some compiler
which i hope it does not.

Originally committed as revision 23115 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavutil/attributes.h

@@ -96,6 +96,14 @@
 #endif
 #endif
 
+#ifndef av_alias
+#if (!defined(__ICC) || __ICC > 1110) && AV_GCC_VERSION_AT_LEAST(3,3)
+#   define av_alias __attribute__((may_alias))
+#else
+#   define av_alias
+#endif
+#endif
+
 #ifndef av_uninit
 #if defined(__GNUC__) && !defined(__ICC)
 #    define av_uninit(x) x=x

libavutil/internal.h

@@ -54,14 +54,6 @@
 #endif
 #endif
 
-#ifndef av_alias
-#if HAVE_ATTRIBUTE_MAY_ALIAS && (!defined(__ICC) || __ICC > 1110) && AV_GCC_VERSION_AT_LEAST(3,3)
-#   define av_alias __attribute__((may_alias))
-#else
-#   define av_alias
-#endif
-#endif
-
 #ifndef INT16_MIN
 #define INT16_MIN       (-0x7fff - 1)
 #endif