I was going through an answer in a post where they define how rough can people be to new users in some cases. There I read:
I have known many good developers that would not use it because of this particular welcoming behavior.
As you see, in this specific case welcome is not following its etymological form of well + come. Instead, is something like not well come.
So, is there an opposite for "welcome"? Could "unwelcome" or "unwelcoming" serve for this purpose? I don't know if such words even exist, since searching for them redirects me to the welcome entry in Dictionary.com.