I missed a publication file when compiling a very old document using
biber.  The only error message I got was

    error: not found

which isn't very helpful.  I've tried to augment the error, now it shows

    error: can't open path `pub.bib`: not found

Hope this is helpful.

The latest version of Alpine Linux seems to provide a static ICU that no
longer has the "macintosh" converter built in. So don't error out if it
fails to load; just hope that everything will be OK.

As per rust-lang/libc#1848, we can't safely do this since the definition
of time_t depends on which version of Musl you're using on 32-bit
systems (the "time64" update for Musl 1.2), and this actually started
biting us on the arm-unknown-linux-musleabihf cross build.
Unfortunately, ISO C makes virtually no guarantees about what time_t is,
so I don't see a practical way to handle the different possibilities
robustly. We'll just cast from i64 or u64 to time_t in C and hope for
the best.