Hi,

I'm facing a weird issue with Emacs 25.2:

With a local http server listening on 127.0.0.1:PORT, `url-retrieve'
fails to open connections on "http://localhost:PORT" with the following
error:

(:error (error connection-failed failed with code 111
 :host localhost :service 3000))

However, connections to "http://127.0.0.1:PORT" work fine.

I cannot reproduce the problem on master where connections to localhost
work fine (curl and browser connections also work fine). 

I tried to find which commit could have fixed the problem, but couldn't.

Does anyone know what was the issue and what fixed it?

Nico