[tlbuild] Support for musl

[Norbert Preining]

On Tue, 23 Jan 2018, Henri wrote:
> Well, TeX live already pulls in specific versions of the libraries instead of always using upstream,

Huu? No, we try to use the latest released versions as far as possible.
Of course, that is released at the time of the binary builds, so the
for 2017 around March 2017 it was.

> so I guess it wouldn't be too bad.  And that is what Debian is doing as well, right?  Using upstream
> and applying Debian-specific patches to make stuff compile.

We are not Debian ;-)
Well yes, we do apply patches but try to keep them to a minimum and feed
them back upstream. Mostly fixes for arcane architectures etc.

I guess it all boils down to
- size of the patches
- maintainability
- will of the patch author to maintain the stuff and update it for new
  releases

> Indeed.  I'm am not requesting that you rewrite all infrastructure right now!  But it is certainly
> something to keep in mind for the future, especially if more Linux distros are picking up musl.  It
> is already in Debian (and others) so it's just a matter of time until they ship musl-based releases.

I will keep it in mind, and in some spare time look into supporting
extended architecture names. Concerning Debian - having musl in there is
not even the slightest indication the Debian wants/will switch to it as
*default* C-lib. I still remember the a.out -> ELF switch which was a
similar pain, and former libc switches (temporary elibsomething), but
they were mostly compatible. It was a huge pain.

> binaries).  Since musl is still kind of esoteric, I would guess that only non-idiot people use it
> and are aware of the consequences, so they should be able to use the custom-bin options without a
> struggle.

Here I agree, normal users will never start playing around with libc
changes, this is also my guess.

Norbert

--
PREINING Norbert                               http://www.preining.info
Accelia Inc.     +    JAIST     +    TeX Live     +    Debian Developer
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