Gentoo中不穩定軟件包有幾種，
1，~amd64（~x86） keyword
這種情況說明make.conf中指明了關鍵字amd64，而不是~amd64關鍵字，這樣所有標有~amd64關鍵字的軟件默認都不會裝上。
$ emerge -pv =vanilla-sources-2.6.16.62
These are the packages that would be merged, in order:
Calculating dependencies...
!!! All ebuilds that could satisfy "=sys-kernel/vanilla-sources-2.6.16.62" have been masked.
!!! One of the following masked packages is required to complete your request:
- sys-kernel/vanilla-sources-2.6.16.62 (masked by: ~amd64 keyword)
[...]
這是程度最輕的，~amd64表示該軟件在amd64架構上尚不穩定，可以通過添加為該軟件添加~amd64關鍵字來安裝：
# echo "=sys-kernel/vanilla-sources-2.6.16.62 ~amd64" >> /etc/portage/package.keywords
# emerge -pv =vanilla-sources-2.6.16.62
These are the packages that would be merged, in order:
Calculating dependencies... done!
[ebuild N ] sys-kernel/vanilla-sources-2.6.16.62 USE="-build -symlink" 40,240 kB
Total: 1 package (1 new), Size of downloads: 40,240 kB
2，missing keyword
這種比表明該軟件在該平台上還沒有規范的測試過，不知是否可用。顯然這樣的軟件一般是無法保障的。
# emerge -pv =vanilla-sources-2.6.27_rc6
These are the packages that would be merged, in order:
Calculating dependencies \
!!! All ebuilds that could satisfy "=sys-kernel/vanilla-sources-2.6.27_rc6" have been masked.
!!! One of the following masked packages is required to complete your request:
- sys-kernel/vanilla-sources-2.6.27_rc6 (masked by: package.mask, missing keyword)
(2.6.27_rc6) [m]~*2.6.27_rc6
這時需要在該軟件的ebuild中加入相應的平台關鍵字，在文件/usr/portage/sys-kernel/vanilla-sources/vanilla-sources-2.6.27_rc6.ebuild中加入~amd64：
KEYWORDS="~alpha ~arm ~hppa ~ia64 ~ppc ~ppc64 ~sparc ~x86 ~amd64"
再
# ebuild /usr/portage/sys-kernel/vanilla-sources/vanilla-sources-2.6.27_rc6.ebuild digest
3， package.mask
這種情況的軟件的穩定程度介於第一種和第三種之間，下面接著第二的例子再emerge一下：
# emerge -pv =vanilla-sources-2.6.27_rc2
These are the packages that would be merged, in order:
Calculating dependencies -^C
Exiting on signal 2
Gentoo-F312-64 example # emerge -pv =vanilla-sources-2.6.27_rc6
These are the packages that would be merged, in order:
Calculating dependencies \
!!! All ebuilds that could satisfy "=sys-kernel/vanilla-sources-2.6.27_rc6" have been masked.
!!! One of the following masked packages is required to complete your request:
- sys-kernel/vanilla-sources-2.6.27_rc6 (masked by: package.mask, ~amd64 keyword)
這時出現了package.mask, ~amd64 keyword，後者第1點已經說到了，對於package.mask，只需：
# echo "=sys-kernel/vanilla-sources-2.6.27_rc6" >> /etc/portage/package.unmask
就可以了，按照第一點，還要接著：
# echo "=sys-kernel/vanilla-sources-2.6.27_rc6 ~amd64" >> /etc/portage/package.keywords
這樣該軟件就ok了：
# emerge -pv =vanilla-sources-2.6.27_rc6
These are the packages that would be merged, in order:
Calculating dependencies... done!
[ebuild N ] sys-kernel/vanilla-sources-2.6.27_rc6 USE="-build -symlink" 62,377 kB
