***** autoconf *****
***** PWD: /var/tmp/portage/media-sound/lame-3.99.5-r1/work/lame-3.99.5
***** autoconf -I . --force

configure.in:394: error: possibly undefined macro: AM_PATH_GTK
      If this token and others are legitimate, please use m4_pattern_allow.
      See the Autoconf documentation.