Here's an update on the progress to run musl (Alpine Linux) in the
buildfarm.
Wolfgang Walther:
The animal runs in a docker container via GitHub Actions in [2]. Right
now it's still running with --test, until I get the credentials to
activate it.
The animals have been activated and are reporting now. Thanks, Andrew!
I tried to enable everything (except systemd, because Alpine doesn't
have it) and run all tests. The LDAP tests are failing right now, but
that is likely something that I need to fix in the Dockerfile - it's
failing to start the slapd, IIRC. There are other issues, though - all
of them have open pull requests in that repo [3].
ldap tests are enabled, just a missing package.
I also had to skip the recovery check. Andrew mentioned that he had to
do that, too, when he was still running his animal on Alpine. Not sure
what this is about, yet.
This was about a missing init process in the docker image. Without an
init process reaping zombie processes, the recovery tests end up with
some supposed-to-be-terminated backends still running and can't start
them up again. Fixed by adding a minimal init process with "tinit".
Building --with-icu fails two tests. One of them (001_initdb) is fixed
by having the "locale" command in your PATH, which is not the case on
Alpine by default. I assume this will not break on your debian/musl
build, Andres - but it will also probably not return any sane values,
because it will run glibc's locale command.
I haven't looked into that in detail, yet, but I think the other test
(icu/010_database) fails because it expects that setlocale(LC_COLLATE,
<illegal_value>) throws an error. I think it doesn't do that on musl,
because LC_COLLATE is not implemented.
Those failing tests are not "just failing", but probably mean that we
need to do something about how we deal with locale/setlocale on musl.
I still need to look into this in depth.
The last failure is about building --with-nls. This fails with something
like:
ld: src/port/strerror.c:72:(.text+0x2d8): undefined reference to
`libintl_gettext'
Of course, gettext-dev is installed, libintl.so is available in /usr/lib
and it also contains the symbol. So not sure what's happening here.
This is an Alpine Linux packaging issue. Theoretically, it could be made
to work by introducing some configure/meson flag like "--with-gettext"
or so, to prefer gettext's libintl over the libc-builtin. However, NixOS
/ nixpkgs with its pkgsMusl overlay manages to solve this issue just
fine, builds with --enable-nls and gettext work. Thus, I conclude this
is best solved upstream in Alpine Linux.
TLDR: The only real issue which is still open from PostgreSQL's side is
around locales and ICU - certainly the pain point in musl. Will look
into it further.
Best,
Wolfgang
