Thread: How did queensnake corrupt zic.o?

Hi,

We see a successful compile and then a failure to read the file while
linking.  We see that the animal got into that state recently and then
fixed itself, and now it's back in that state.  I don't know if it's
significant, but it happened to fix itself when a configure change
came along, which might be explained by ccache invalidation; that is,
the failure mode doesn't depend on the input files, but once it's
borked you need a change to kick ccache.  My memory may be playing
tricks on me but I vaguely recall seeing another animal do this, a
while back.

Thomas Munro <thomas.munro@gmail.com> writes:
> We see a successful compile and then a failure to read the file while
> linking.  We see that the animal got into that state recently and then
> fixed itself, and now it's back in that state.  I don't know if it's
> significant, but it happened to fix itself when a configure change
> came along, which might be explained by ccache invalidation; that is,
> the failure mode doesn't depend on the input files, but once it's
> borked you need a change to kick ccache.  My memory may be playing
> tricks on me but I vaguely recall seeing another animal do this, a
> while back.

queensnake's seen repeated cycles of unexplainable build failures.
I wonder if it's using a bogus ccache version, or if the machine
itself is flaky.

            regards, tom lane

Hi,

On 2022-02-15 10:00:45 -0300, Filipe Rosset wrote:
> I had to disable ccache on queensnake, all builds are fine right now. Let's
> see how it goes.

> due OS migration on queensnake (scientific linux -> centos -> rocky linux)
> I think it's time to decommission the queensnake and request a new animal
> for a new server, maybe.

Did you keep the ccache cache across these migrations? If so, I'd not at all
be surprised if that caused the problem. I don't think ccache is going to be
reliably protecting against all the things changing between distrubtion
[versions]. Particularly not if the ccache version also changed.

Greetings,

Andres Freund