diff --git a/lz4-sys/src/lib.rs b/lz4-sys/src/lib.rs
index 559809e19..115f3bb53 100644
--- a/lz4-sys/src/lib.rs
+++ b/lz4-sys/src/lib.rs
@@ -140,12 +140,10 @@ pub struct LZ4FDecompressOptions {
     pub reserved: [c_uint; 3],
 }
 
-#[derive(Debug)]
-#[repr(C)]
+#[repr(transparent)]
 pub struct LZ4StreamEncode(c_void);
 
-#[derive(Debug)]
-#[repr(C)]
+#[repr(transparent)]
 pub struct LZ4StreamDecode(c_void);
 
 pub const LZ4F_VERSION: c_uint = 100;