diff --git a/LZMA/LzmaCompress.c b/LZMA/LzmaCompress.c
index 78c04a3..d2b5f5e 100644
--- a/LZMA/LzmaCompress.c
+++ b/LZMA/LzmaCompress.c
@@ -74,7 +74,7 @@ LzmaCompress(
 
 	if (*DestinationSize < destLen)
 	{
-		*DestinationSize = destLen;
+		*DestinationSize = (UINTN)destLen;
 		return ERR_BUFFER_TOO_SMALL;
 	}