diff --git a/external/sourcesdk/bitbuf.cpp b/external/sourcesdk/bitbuf.cpp
index f0c672e..3597775 100644
--- a/external/sourcesdk/bitbuf.cpp
+++ b/external/sourcesdk/bitbuf.cpp
@@ -1063,7 +1063,7 @@ int32 bf_read::ReadSignedVarInt32()
 
 int64 bf_read::ReadSignedVarInt64()
 {
-	uint32 value = ReadVarInt64();
+	uint64 value = ReadVarInt64();
 	return bitbuf::ZigZagDecode64( value );
 }