Hi Peff, On Sat, 26 Oct 2019, Jeff King wrote: > On Sat, Oct 26, 2019 at 10:56:45PM +0200, Johannes Schindelin wrote: > > > Back to the issue at hand: I did open a GitGitGadget PR with my proposed > > change, in the hopes that I could somehow fast-track this fix into the > > CI/PR builds over at https://github.com/gitgitgadget/git, but there are > > problems: it seems that now there is an at least occasional broken pipe > > in the same test when run on macOS. > > Yes, I think that's another issue in the same test. There's more > discussion further down in the thread I linked earlier, starting here: > > https://public-inbox.org/git/20190829143805.GB1746@xxxxxxxxxxxxxxxxxxxxx/ > > and I think Gábor's solution here: > > https://public-inbox.org/git/20190830121005.GI8571@xxxxxxxxxx/ > > is the right direction (and note that this _isn't_ just a test artifact, > but a bug that occasionally hits real-world cases, too). That sounds good! I guess I should continue _that_ thread. > > There _also_ seems to be something spooky going on in t3510.12 and .13, > > where the expected output differs from the actual output only by a > > re-ordering of the lines: > > > > -- snip -- > > [...] > > +++ diff -u expect advice > > --- expect 2019-10-25 22:17:44.982884700 +0000 > > +++ advice 2019-10-25 22:17:45.278884500 +0000 > > @@ -1,3 +1,3 @@ > > error: cherry-pick is already in progress > > -hint: try "git cherry-pick (--continue | --skip | --abort | --quit)" > > fatal: cherry-pick failed > > +hint: try "git cherry-pick (--continue | --skip | --abort | --quit)" > > -- snap -- > > Hrm. I'd have thought those are both coming from the same process. Which > implies that we're not fflushing stderr before calling write(2). But > your patch seems to do so... > > <scratches head> Aha. I think you force-pushed up as I am typing this. > :) So I think that is indeed the solution. Yes, sorry, I had this idea and it worked locally, and I wanted to know whether it would turn the PR build green. > > So much as I would love to see the flakiness of t5516 be fixed as soon > > as possible, I fear we will have to look at the underlying issue a bit > > closer: there are two processes writing to `stderr` concurrently. I > > don't know whether there would be a good way for the `stderr` of the > > `upload-pack` process to be consumed by the `fetch` process, and to be > > printed by the latter. > > The worst part is that this message already _is_ consumed by fetch: we > send it twice, once over the sideband, and once directly to stderr. In > most cases the stderr version is lost, but some server providers might > be collecting it. I wouldn't mind seeing the direct-to-stderr one > dropped. There's some more discussion in (from the same thread linked > earlier): > > https://public-inbox.org/git/20190828145412.GB14432@xxxxxxxxxxxxxxxxxxxxx/ It is tricky all right. Full disclosure: I am mainly interested in having lots less failing builds (which I all re-run manually when I see that a known-flaky test failed). Ciao, Dscho
