\pdfmajorversion

[Vincent Torri]

On Sun, Oct 27, 2019 at 12:54 AM Karl Berry <karl at freefriends.org> wrote:
>
> Hi Max -
>
>     The current master of poppler uses C++14, which is now 5 years old.
>
> I had the impression that current poppler sources require C++17.
>
> Anyway, the chronological age of a standard doesn't much matter. What
> matters is what distro-provided compilers support. The CentOS 7
> compiler, for example, doesn't support C++14. And even CentOS 6 (doesn't
> support C++11) has not yet reached end of life. Such problems occur with
> other distros too.
>
>     * Is there a list of OSes that should still be supported?
>
> There is no particular list. We support as old of systems as we
> reasonably can.
>
>     * When is a decision made to drop old systems?
>
> When it's no longer reasonable. The volunteers who build the TL binaries
> for system X are the ones who ultimately decide what can be reasonably
> supported.
>
>     * Wouldn't it be okay for old systems just to install a compatible older
>     release?
>
> If you mean an older TeX release, then, no. TeX users would not be happy
> to be forced to live with an old, un-updatable, release just because
> some third party library, which is a tiny part of the overall TeX world,
> can no longer be compiled on their system.
>
> In general, the TeX world has a long history of trying to be as portable
> as possible, since after all TeX itself is completely portable, and TeX
> distributions were happening years before the current kernels (Linux,
> BSD, Solaris, ...) existed.
>
> There continues to be a nontrivial number of people who cannot use the
> binaries we compile now, which require C++11 (because of the glibc
> implications).  We regretfully had to make that change because not just
> poppler, but also ICU, started requiring the newer C++, and there was no
> general workaround for that. It is a big hassle both for builders and for users.
>
> The only way to deal with that is to compile and use a newer compiler on
> the older system, which has plenty of its own problems. Nelson Beebe has
> succeeded with that approach (among many other necessary changes) on a
> huge variety of systems, but it's not feasible to require that much work
> of the volunteers who build the binaries we distribute with TL.
> http://tug.org/texlive/bugs.html
> http://tug.org/texlive/custom-bin.html
>
> Anyway, as far as poppler goes, the only thing it's used for in the TeX
> tree is to read PDF files in batch, which is a small fraction of its
> functionality. So the ultimate goal is to stop using poppler entirely
> and use pplib, written in C by Pawel Jackowski. It's being used in
> luatex as of the TL 2019 release, and we hope to extend it to other
> engines if we (that is, Luigi Scarso, the luatex maintainer) can make it
> reliable enough. We'll see.

mupdf is written in C, I use it in one of my pet projects. it's AGPL3 though

Vincent Torri