In Connection.CompressWireMessage() we currently copy src into dst when using no compression:

if c.connection.compressor == wiremessage.CompressorNoOp {
    return append(dst, src...), nil
} 

Can we just set dst = src? I made this change and tested with mongorestore and it seemed to work fine, but I'm wondering if the underlying array can be mutated through dst at a later point which would cause problems for code still using src.