Libguestfs - Aug 2021 - Problem building appliance/guestfsd.deps on debian

Hi hillu,

We have a report of a problem with building appliance/guestfsd.deps on
Debian 10.  This code which you contributed:

https://github.com/libguestfs/libguestfs/commit/133a49167778195f0cf043a1d380c60956aa46b1

seems to cause problems with certain libraries which are symlinks.  In
particular:

dpkg-query: no path found matching pattern /lib/x86_64-linux-gnu/libacl.so.1

(and for some other libraries) which causes the final guestfsd.deps to
be incomplete.  Note /lib/x86_64-linux-gnu/libacl.so.1 exists but is a
symlink.

When the reporter tries to boot the appliance, guestfsd cannot be
loaded because:

guestfsd: error while loading shared libraries: libjansson.so.4: cannot open
shared object file: No such file or directory

Any ideas what's going on here?

Thanks,

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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* Richard W.M. Jones:
> We have a report of a problem with building appliance/guestfsd.deps on
> Debian 10.  This code which you contributed:
>
>
https://github.com/libguestfs/libguestfs/commit/133a49167778195f0cf043a1d380c60956aa46b1
>
> seems to cause problems with certain libraries which are symlinks.  In
> particular:
>
> dpkg-query: no path found matching pattern
/lib/x86_64-linux-gnu/libacl.so.1
I suppose that the problematic symlink is not

    libacl.so.1 -> libacl.so.1.1.2253 (or similar)

but rather

    /lib -> /usr/lib

"ldconfig -p" lists only /lib/<triplet> paths because its
configuration
(at least on my systems) prefers /lib/<triplet> befreo
/usr/lib/<triplet>.

Since my contributed code was inspired by what dpkg-shlibdeps does, I
suspect that its maintainers might have run into similar problems when
usrmerge was introduced. I'll investigate what solution they came up
with (because I can't think of anything foolproof).

Cheers,
-Hilko