I can see aclocal’ srearch path with aclocal --print-ac-dir
It was /opt/libtool/share/aclocal
But there isn’t any resource without README.
In my case aclocal is installed different with automake
And there is some m4 related files in /opt/automake/share/aclocal
Then I made symbolic link to /opt/automake/share/aclocal
/opt/libtool/share/aclocal-> /opt/automake/share/aclocal
Now automake completes with no error.