Misaki Shioi a8c3d5e127
Fix: Do not fast_fallback if local_port is explicitly specified (#15732)
`fast fallback` cannot be used with explicitly specified local port,
because concurrent binds to the same `local_host:local_port`
can raise `Errno::EADDRINUSE`.

This issue is more likely to occur on hosts with `IPV6_V6ONLY` disabled,
because IPv6 binds can also occupy IPv4-mapped IPv6 address space.
2025-12-27 18:26:56 +09:00
..