This will be solved by #51748 in Go 1.18.2, but I agree that it's unexpected that go fmt would do any VCS build stamping at all. It shouldn't be doing any building.

Will the fix be backported? Ultimately that doesn't actually matter to me unless backporting would happen sooner than the 18.2 release. Otherwise I'd just upgrade. But still curious.

Given that 1.18.1 is out, 1.18.2 is the soonest release it can be in. Backport issue is #51798

Well that's about changing build behavior, right? With go fmt I can't explicitly enable or disable vcs stamping - because it shouldn't need to do that at all, no? gofmt itself doesn't do anything like that, just seems like a true bug in the invocation. Because if it does find git then according to the proposal for --buildvcs=auto in #51798, the go fmt run will fail if invocation of git fails for some reason. But go fmt shouldn't depend on git at all, because gofmt doesn't.

Right, this seems like a regression bug. I imagine 1.18.2 will be out sometime over the next week; it's already been four weeks since 1.18 and usually there would have been a bugfix release two weeks ago.

I think keeping this issue open is worthwhile because it's not a dupliate; as already stated, there's presumably no reason for go fmt to stamp VCS information.

I believe it may have been unintentionally fixed in 1.18.1 already by #51723, which restricts when buildvcs is included (eg go run doesn't have it now, #52338).
strace -f go fmt 2>&1 | grep execve doesn't show git being called for 1.18.1, but it does for 1.18

Ah, you're right. 1.18.1 was announced as a security release, so I assumed it only contained security fixes, but it doesn't.

I didn't check 1.18.1 - didn't realize that existed when I wrote the example. I'll check that out and close the issue if it's resolved in the newest release. (or should I leave it open for tracking backport?)

1.18.1 doesn't have this problem