diff --git a/libavutil/intreadwrite.h b/libavutil/intreadwrite.h
index c4679fdba4..21df7887f3 100644
--- a/libavutil/intreadwrite.h
+++ b/libavutil/intreadwrite.h
@@ -213,7 +213,7 @@ typedef union {
  * by per-arch headers.
  */
 
-#if defined(__GNUC__)
+#if defined(__GNUC__) || defined(__clang__)
 
 union unaligned_64 { uint64_t l; } __attribute__((packed)) av_alias;
 union unaligned_32 { uint32_t l; } __attribute__((packed)) av_alias;