Today's accomplishment: got sufficiently irritated by Go failing self-tests on stock FreeBSD systems that I finally filed a report on the second issue: https://github.com/golang/go/issues/77411

The first issue on stock FreeBSD is https://github.com/golang/go/issues/70702

It's very obvious that approximately nobody runs Go's all.bash on real FreeBSD systems. At best it is "tested" on Go's builder machines, which are clearly non-standard in multiple ways.

My "Go failing selftests for its net package on FreeBSD" issue¹ turns out to be specific to FreeBSD 15. Evidently there's some networking change that is doing something different from what Go is counting on. If I'm energetic, I can peruse FreeBSD changelogs and stuff.

(It's possible all of the failures involve IPv6 / IPv4 interactions.)

¹ https://github.com/golang/go/issues/77411

net: consistent all.bash failure on stock FreeBSD 15 · Issue #77411 · golang/go

Go version go version go1.25.6 freebsd/amd64 also go version go1.27-devel_d99be5c444 Mon Feb 2 01:42:56 2026 -0800 freebsd Output of go env in your module/workspace: AR='ar' CC='clang' CGO_CFLAGS='...

GitHub

I believe I've found the FreeBSD 15 networking change that breaks Go's net package self-tests, and it's an interesting one¹. As described in the release notes²:

Making a connection to INADDR_ANY, i.e., using it as an alias for localhost, is now disabled by default. This functionality can be re-enabled by setting the net.inet.ip.connect_inaddr_wild sysctl to 1.

I can see the point, even though this is a behavior change.

¹ https://cgit.freebsd.org/src/commit/?id=cd240957d7ba
² https://www.freebsd.org/releases/15.0R/relnotes/#network-general

src - FreeBSD source tree

This is my face that you can do 'ssh 0' (assuming your machine runs a SSH daemon) and it will probably work. Well, unless you're on FreeBSD 15. Or OpenBSD, which laughs at you.

For proper credit (or if you prefer, blame), I learned about 'ssh 0' from a comment @lyda left on my techblog. But now that I've seen it I can't unsee it. What else will accept '0' as a hostname? Feel free to try it today.

(Firefox will, it looks like.)

@cks I never learned to type so I'll use any shortcut going! Pretty sure I learned telnet 0 back when I was learning about socket programming - then applied it to ssh. I didn't learn 127.1 until someone explained similar behaviour in ipv6. Obviously more useful there.