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.