invalid length of startup packet

[francoricci]

• asyncpg version: 0.18.2
• PostgreSQL version: 9.6.8
• Do you use a PostgreSQL SaaS? If so, which? Can you reproduce
  the issue with a local PostgreSQL install?: NO
• Python version: 3.6.7
• Platform: FreeBSD 11.2
• Do you use pgbouncer?: NO
• Did you install asyncpg with pip?: YES
• If you built asyncpg locally, which version of Cython did you use?:
• Can the issue be reproduced under both asyncio and
  uvloop?: YES

import asyncio
import asyncpg
import uvloop

async def run():
conn = await asyncpg.connect(host='127.0.0.1', port='5432', user='root', password='pippo', database='postgres', ssl=None)
values = await conn.fetch("SELECT * FROM pg_type")
await conn.close()

asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())
loop = asyncio.get_event_loop()
loop.run_until_complete(run())

returns:

asyncpg.exceptions.ConnectionDoesNotExistError: connection was closed in the middle of operation
and postgresql:
LOG: invalid length of startup packet

With previous asyncpg version 0.17.0 all works well.
See issue #313

[elprans]

Fix released in 0.18.3.

[francoricci]

Great.
Thanks a lot!!!