diff --git a/sys/src/avcodec/codec.rs b/sys/src/avcodec/codec.rs
index 35438d9..ea68fe6 100644
--- a/sys/src/avcodec/codec.rs
+++ b/sys/src/avcodec/codec.rs
@@ -660,7 +660,7 @@ pub struct AVPacket {
 	pub side_data: *mut AVPacketSideData,
 	pub side_data_elems: c_int,
 	pub duration: c_int,
-	pub destruct: extern fn(*mut AVPacket), // XXX: #if FF_API_DESTRUCT_PACKET
+	pub destruct: Option<extern fn(*mut AVPacket)>, // XXX: #if FF_API_DESTRUCT_PACKET
 	pub private: *mut c_void, // XXX: #if FF_API_DESTRUCT_PACKET
 	pub pos: int64_t,
 	pub convergence_duration: int64_t,