Hello~

Yesterday, I did update my gentoo like this.

$ sudo emerge --update --deep --newuse world
As a result, one of the updated package tiff said like this.
** Messages for package media-libs/tiff-3.8.2-r5:


** JBIG support is intended for Hylafax fax compression, so we
** really need more feedback in other areas (most testing has
** been done with fax).* Be sure to recompile anything linked
** against tiff if you rebuild it with jbig support.


So I checked what package linked with libtiff(Actually, there is no need to do this. I just want to know).

$ revdep-rebuild -p --library /usr/lib/libtiff.so.3

Then, revdep-rebuild display like this.
[ebuild** R** ] media-libs/tiff-3.8.2-r5

[ebuild** R** ] media-gfx/imagemagick-6.4.3.5
[ebuild** R** ] media-libs/lcms-1.17
[ebuild**** U ] media-libs/vigra-1.6.0 [1.5.0-r1]
[ebuild** R** ] net-print/cups-1.3.8-r1
[ebuild** R** ] x11-libs/gtk+-2.12.12

[ebuild** R** ] app-text/ghostscript-gpl-8.63
[ebuild** R** ] app-text/evince-2.22.2-r1
[ebuild** R** ] media-gfx/gthumb-2.10.9


As you can see, there is a package "vigra" with flag "U".

As I know, U is need to update, and if I do emerge --update world, it will be update.

But there is no "vigra" in result of "emerge -p --update world"(with --deep also).
Of course, it still shows flag "U" if I do "emerge -p vigra"


What is difference with emerge --update world and emerge vigra?
And how can I update all new package without exceptions?

If you know, please let me know.