Please remove bashisms from config.site script. /bin/sh is a symlink to dash on my system and I see following warnings (e.g. when emerging ncurses): # grep config.site /var/tmp/portage/sys-libs/ncurses-5.9-r2/temp/build.log configure: loading site script /usr/share/config.site /var/tmp/portage/sys-libs/ncurses-5.9-r2/work/ncurses-5.9/configure: 40: /usr/share/config.site: [[: not found configure: loading site script /usr/share/config.site /var/tmp/portage/sys-libs/ncurses-5.9-r2/work/ncurses-5.9/configure: 40: /usr/share/config.site: [[: not found
http://www.gnu.org/software/automake/manual/html_node/config_002esite.html "If a file named prefix/share/config.site exists, configure will source it at the beginning of its execution." configure: loading site script /usr/share/config.site /var/tmp/portage/x11-apps/xrandr-1.4.3/work/xrandr-1.4.3/configure: 40: /usr/share/config.site: [[: not found There's no reason to think that configure scripts would or should "reload in bash".
With dash-0.5.8.1 recently landed into the tree more configure scripts start choosing /bin/sh instead of /bin/bash
http://git.overlays.gentoo.org/gitweb/?p=proj/crossdev.git;a=commitdiff;h=ef7d323880dd0ad1e322f8debb9f4b400c580b71
*** Bug 529734 has been marked as a duplicate of this bug. ***