mpv 1

!sudo apt-get install autoconf

Reading package lists... Done
Building dependency tree
Reading state information... Done
autoconf is already the newest version (2.69-11).
The following package was automatically installed and is no longer required:
  libnvidia-common-460
Use 'sudo apt autoremove' to remove it.
0 upgraded, 0 newly installed, 0 to remove and 47 not upgraded.

!./rebuild -j8

+ git pull --rebase
Already up to date.
Current branch master is up to date.
+ do_clone_all
+ do_clone ffmpeg https://github.com/FFmpeg/FFmpeg.git
+ set -ex
+ test -e ffmpeg
+ cd ffmpeg
+ git remote set-url origin https://github.com/FFmpeg/FFmpeg.git
+ git fetch
remote: Enumerating objects: 38, done.
remote: Counting objects: 100% (38/38), done.
remote: Compressing objects: 100% (7/7), done.
remote: Total 38 (delta 31), reused 38 (delta 31), pack-reused 0
Unpacking objects: 100% (38/38), done.
From https://github.com/FFmpeg/FFmpeg
   33fe3b73c2..1b8647cfdc  master     -> origin/master
+ do_clone libass https://github.com/libass/libass.git
+ set -ex
+ test -e libass
+ cd libass
+ git remote set-url origin https://github.com/libass/libass.git
+ git fetch
+ do_clone mpv https://github.com/mpv-player/mpv.git
+ set -ex
+ test -e mpv
+ cd mpv
+ git remote set-url origin https://github.com/mpv-player/mpv.git
+ git fetch
+ checkout ffmpeg master
+ local branch=master
+ [ -z  ]
+ [ -d config/ ]
+ do_gitmaster ffmpeg
+ set -ex
+ cd ffmpeg
+ git checkout origin/master
Previous HEAD position was 33fe3b73c2 avcodec/tests/snowenc: Remove unused-but-set variable
HEAD is now at 1b8647cfdc fate: add PFM encoder tests
+ git remote prune origin
+ checkout libass master
+ local branch=master
+ [ -z  ]
+ [ -d config/ ]
+ do_gitmaster libass
+ set -ex
+ cd libass
+ git checkout origin/master
HEAD is now at a2b39cd Switch to non-recursive Makefile
+ git remote prune origin
+ checkout mpv master
+ local branch=master
+ [ -z  ]
+ [ -d config/ ]
+ do_gitmaster mpv
+ set -ex
+ cd mpv
+ git checkout origin/master
HEAD is now at 369168b9be context_x11egl: remove supposed transparency fix
+ git remote prune origin
+ do_update_debian_versions
+ scripts/debian-update-versions
+ do_bootstrap
+ scripts/mpv-bootstrap
Found 'waf', skipping download.
'distclean' finished successfully (0.005s)
Running autoreconf...
autoreconf: Entering directory `.'
autoreconf: configure.ac: not using Gettext
autoreconf: running: aclocal --force -I m4
autoreconf: configure.ac: tracing
autoreconf: configure.ac: not using Libtool
autoreconf: running: /usr/bin/autoconf --force
autoreconf: running: /usr/bin/autoheader --force
autoreconf: running: automake --add-missing --copy --force-missing
configure.ac:11: installing './compile'
configure.ac:2: installing './install-sh'
configure.ac:2: installing './missing'
Makefile.am:12: error: Libtool library used but 'LIBTOOL' is undefined
Makefile.am:12:   The usual way to define 'LIBTOOL' is to add 'LT_INIT'
Makefile.am:12:   to 'configure.ac' and run 'aclocal' and 'autoconf' again.
Makefile.am:12:   If 'LT_INIT' is in 'configure.ac', make sure
Makefile.am:12:   its definition is in aclocal's search path.
Makefile.am: installing './depcomp'
autoreconf: automake failed with exit status: 1