Merge commit '5858a67f'

* commit '5858a67f':
  attributes: disable flatten on llvm/clang

Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavutil/attributes.h

@@ -76,7 +76,7 @@
 #    define av_cold
 #endif
 
-#if AV_GCC_VERSION_AT_LEAST(4,1)
+#if AV_GCC_VERSION_AT_LEAST(4,1) && !defined(__llvm__)
 #    define av_flatten __attribute__((flatten))
 #else
 #    define av_flatten