autoreconf fail

[andreasschulze]

$ cd /tmp
$ git clone https://github.com/rscada/libmbus.git
$ cd libmbus/
$ aclocal --version
aclocal (GNU automake) 1.16.1
...
$ aclocal
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
/usr/share/aclocal-1.16/ar-lib.m4:13: AM_PROG_AR is expanded from...
configure.ac:19: the top level

$ autoreconf --version
autoreconf (GNU Autoconf) 2.69
$ autoreconf -i
aclocal: warnings are treated as errors
aclocal: warning: couldn't open directory 'm4': No such file or directory
autoreconf: aclocal failed with exit status: 1

to fix that issue, I install an empty m4/

$ install -d m4/
$ autoreconf -if
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
/usr/share/aclocal-1.16/ar-lib.m4:13: AM_PROG_AR is expanded from...
configure.ac:19: the top level
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
aclocal.m4:70: AM_PROG_AR is expanded from...
configure.ac:19: the top level
libtoolize: putting auxiliary files in AC_CONFIG_AUX_DIR, 'libltdl/config'.
libtoolize: copying file 'libltdl/config/compile'
libtoolize: copying file 'libltdl/config/config.guess'
libtoolize: copying file 'libltdl/config/config.sub'
libtoolize: copying file 'libltdl/config/depcomp'
libtoolize: copying file 'libltdl/config/install-sh'
libtoolize: copying file 'libltdl/config/missing'
libtoolize: copying file 'libltdl/config/ltmain.sh'
libtoolize: putting macros in 'm4'.
libtoolize: copying file 'm4/libtool.m4'
libtoolize: copying file 'm4/ltoptions.m4'
libtoolize: copying file 'm4/ltsugar.m4'
libtoolize: copying file 'm4/ltversion.m4'
libtoolize: copying file 'm4/lt~obsolete.m4'
libtoolize: Consider adding 'AC_CONFIG_MACRO_DIRS([m4])' to configure.ac,
libtoolize: and rerunning libtoolize and aclocal.
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
/usr/share/aclocal-1.16/ar-lib.m4:13: AM_PROG_AR is expanded from...
configure.ac:19: the top level
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
aclocal.m4:70: AM_PROG_AR is expanded from...
configure.ac:19: the top level
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
aclocal.m4:70: AM_PROG_AR is expanded from...
configure.ac:19: the top level
configure.ac:19: warning: LT_INIT was called before AM_PROG_AR
aclocal.m4:70: AM_PROG_AR is expanded from...
configure.ac:19: the top level

an other option to avoid this error is to remove -I m4 from https://github.com/rscada/libmbus/blob/master/Makefile.am#L20