net: TestFilePacketConn/udp failures

[gopherbot]

#!watchflakes
default <- pkg == "net" && test == "TestFilePacketConn/udp"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestFilePacketConn/udp
    file_test.go:275: file file+net udp4:127.0.0.1:56164->: getsockname: An invalid argument was supplied.
--- FAIL: TestFilePacketConn/udp (0.00s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "net" && test == "TestFilePacketConn/udp"

2026-03-11 03:06 gotip-windows-386 go@38ac6577 net.TestFilePacketConn/udp (log)

=== RUN   TestFilePacketConn/udp
    file_test.go:275: file file+net udp4:127.0.0.1:56164->: getsockname: An invalid argument was supplied.
--- FAIL: TestFilePacketConn/udp (0.00s)

— watchflakes