--with-system-zlib and texdoc,lualatex,...

[Karl Berry]

    >      if (strncmp(version, ZLIB_VERSION, 2))

    We only compare the major and minor version here (13 vs 13) ... why
    does it complain?

Indeed.

Johannes: is the version that panics some older or distro binary? As I
recall, Luigi made that change to check only the major version recently,
precisely to avoid the problem you are seeing. (And maybe we did it in
other places too, not sure.) I asked him. --thanks, karl.