grub2 should install a defaults file in /etc/default/grub (or alternatively taking into account the gentoo filesystem, /etc/conf.d. The problem is that this file is not installed, and there is no example for how this file should look. It is needed for configuring default options passed to the kernel at boot time for example, customizing kernel command line. I bumped into this when trying to set up hibernation, for which I need to add a resume= option to my kernel commandline Reproducible: Always Steps to Reproduce: 1. emerge =sys-boot/grub-1.98 2. try customizing the kernel command-line generated by grub-mkconfig using /etc/default/grub Actual Results: the file doesn't exist and so it is difficult to know what options exist, what their names are. Expected Results: /etc/default/grub exists and has the defaults in it i think debian has a good example file if it is not in the grub upstream distribution.
The wiki has interesting information about this: http://en.gentoo-wiki.com/wiki/Grub2#Using_variables
the grub info page explains the file /etc/conf.d/ is only for init.d scripts which this is not grub-9999 now installs a simple /etc/defaults/grub file with pointers to different pieces of documentation
*** Bug 364763 has been marked as a duplicate of this bug. ***