What steps will reproduce the problem?

TestUnixAutobindClose in the following CL panics:

https://golang.org/cl/13457058/

panic: runtime error: index out of range

goroutine 4 [running]:
runtime.panic(0x5dd8c0, 0xc210070390)
    /home/alberts/go.tip/src/pkg/runtime/panic.c:266 +0xb6
testing.func·005()
    /home/alberts/go.tip/src/pkg/testing/testing.go:383 +0xe8
runtime.panic(0x5dd8c0, 0xc210070390)
    /home/alberts/go.tip/src/pkg/runtime/panic.c:248 +0x106
net.(*UnixListener).Close(0xc21006cf40, 0x4, 0xc21006cf00)
    /home/alberts/go.tip/src/pkg/net/unixsock_posix.go:319 +0x98
net.TestUnixAutobindClose(0xc21006d090)
    /home/alberts/go.tip/src/pkg/net/unix_test.go:151 +0x150
testing.tRunner(0xc21006d090, 0x828e08)
    /home/alberts/go.tip/src/pkg/testing/testing.go:389 +0x8b
created by testing.RunTests
    /home/alberts/go.tip/src/pkg/testing/testing.go:469 +0x8b2

this is because laddr.Name is an empty string, but the code checks for Name[0] being
equal to '@'.

What do you see instead?

panic

Which compiler are you using (5g, 6g, 8g, gccgo)?

6g

Which operating system are you using?

linux

Which version are you using?  (run 'go version')

tip

Please provide any additional information below.

https://golang.org/cl/13457058/