Build fails for arm64/aarch64

[probonopd]

Build for every architecture on Travis CI or GitLab.
E.g., using Alpine Linux Docker images.

[probonopd]

Right now some of the aarch64 builds fail.

This script, last modified 2005-12-13, has failed to recognize
the operating system you are using. It is advised that you
download the most up to date version of the config scripts from
  http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/config/config/config.guess
and
  http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/config/config/config.sub
If the version you run (./config.guess) is already up to date, please
send the following data and any information you think might be
pertinent to <config-patches@gnu.org> in order to provide the needed
information to handle your system.

Yet the build is still "green".

Why?

[probonopd]

Now getting

aclocal: warning: autoconf input should be named 'configure.ac', not 'configure.in'

configure.in:16: warning: macro 'AM_PROG_LIBTOOL' not found in library

configure.in:16: error: possibly undefined macro: AM_PROG_LIBTOOL

      If this token and others are legitimate, please use m4_pattern_allow.

      See the Autoconf documentation.

autoreconf: /usr/bin/autoconf failed with exit status: 1

[probonopd]

Now getting

undefined reference to `__extenddftf2'

Similar to

rust-lang/rust#46651

Build log:
https://api.travis-ci.com/v3/job/326651303/log.txt

Maybe @TheAssassin has an idea?

[probonopd]

Was fixed by using gcc -static instead of ld -static. Thanks nsz on IRC