How can world need new packages?

[mauricev]

After a fresh install, running emerge -vpe world results in emerge wanting to add the following packages.

[ebuild  N     ] app-text/sgml-common-0.6.3-r5::gentoo  126 KiB
[ebuild  N     ] sys-devel/autoconf-archive-2016.09.16::gentoo  610 KiB
[ebuild  N     ] dev-libs/libaio-0.3.110::gentoo  USE="-static-libs {-test}" ABI_X86="(64) -32 (-x32)" 42 KiB
[ebuild  N     ] dev-util/gperf-3.0.4::gentoo  961 KiB
[ebuild  N     ] app-text/build-docbook-catalog-1.21::gentoo  5 KiB
[ebuild  N     ] app-text/docbook-xsl-stylesheets-1.79.1-r1::gentoo  USE="-ruby" 21,454 KiB
[ebuild  N     ] app-text/docbook-xml-dtd-4.1.2-r6:4.1.2::gentoo  74 KiB
[ebuild  N     ] virtual/perl-Parse-CPAN-Meta-1.441.700-r2::gentoo  0 KiB
[ebuild  N     ] virtual/perl-CPAN-Meta-YAML-0.18.0-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-version-0.991.600-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-podlators-4.70.0-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-Text-ParseWords-3.300.0-r2::gentoo  0 KiB
[ebuild  N     ] virtual/perl-Perl-OSType-1.9.0-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-Module-Metadata-1.0.31-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-Getopt-Long-2.480.0-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-ExtUtils-ParseXS-3.310.0-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-ExtUtils-Manifest-1.700.0-r3::gentoo  0 KiB
[ebuild  N     ] virtual/perl-ExtUtils-Install-2.40.0-r2::gentoo  0 KiB
[ebuild  N     ] virtual/perl-ExtUtils-CBuilder-0.280.225-r1::gentoo  0 KiB
[ebuild  N     ] virtual/perl-JSON-PP-2.273.0-r4::gentoo  0 KiB
[ebuild  N     ] virtual/perl-CPAN-Meta-2.150.5-r1::gentoo  0 KiB
[ebuild  N     ] sys-fs/mdadm-4.0::gentoo  USE="static" 500 KiB
[ebuild  N     ] dev-util/boost-build-1.62.0-r1::gentoo  USE="python -examples {-test}" PYTHON_TARGETS="python2_7" 82,533 KiB
[ebuild  N     ] sys-block/thin-provisioning-tools-0.6.3::gentoo  USE="-static {-test}" 195 KiB
[ebuild  N     ] dev-python/cython-0.25.2::gentoo  USE="-doc -emacs {-test}" PYTHON_TARGETS="python2_7 python3_4 -python3_5 -python3_6" 1,664 KiB
[ebuild  N     ] sys-fs/lvm2-2.02.145::gentoo  USE="lvm1 readline static thin -clvm -cman -corosync -device-mapper-only -lvm2create_initrd -openais (-selinux) -static-libs -systemd -udev" 1,940 KiB
[ebuild  N     ] dev-perl/Module-Build-0.421.800::gentoo  USE="{-test}" 299 KiB
[ebuild  N     ] dev-util/gtk-doc-am-1.25-r1::gentoo  658 KiB
[ebuild  N     ] dev-perl/TermReadKey-2.330.0::gentoo  81 KiB
[ebuild  N     ] dev-perl/Text-CharWidth-0.40.0-r1::gentoo  9 KiB
[ebuild  N     ] dev-perl/XML-Parser-2.440.0::gentoo  232 KiB
[ebuild  N     ] dev-perl/SGMLSpm-1.1-r1::gentoo  112 KiB
[ebuild  N     ] dev-perl/Text-WrapI18N-0.60.0-r1::gentoo  4 KiB
[ebuild  N     ] dev-util/intltool-0.51.0-r1::gentoo  159 KiB
[ebuild  NS    ] sys-devel/automake-1.13.4-r1:1.13::gentoo [1.15-r2:1.15::gentoo] 1,416 KiB
[ebuild  NS    ] sys-devel/automake-1.14.1-r1:1.14::gentoo [1.15-r2:1.15::gentoo] 1,455 KiB
[ebuild  N     ] app-text/opensp-1.5.2-r4::gentoo  USE="nls -doc -static-libs {-test}" 1,486 KiB
[ebuild  N     ] sys-fs/cryptsetup-1.7.2::gentoo  USE="gcrypt nls python -kernel -libressl -nettle -openssl -pwquality -reencrypt -static -static-libs -udev -urandom" PYTHON_TARGETS="python2_7 python3_4 -python3_5" 1,195 KiB
[ebuild  N     ] app-text/openjade-1.3.2-r7::gentoo  USE="-static-libs" 874 KiB
[ebuild  N     ] dev-libs/libxslt-1.1.29-r1::gentoo  USE="crypt python -debug -examples -static-libs" ABI_X86="(64) -32 (-x32)" PYTHON_TARGETS="python2_7" 3,349 KiB
[ebuild  N     ] sys-kernel/genkernel-3.4.40.13::gentoo  USE="cryptsetup -btrfs (-ibm) (-selinux)" 12,966 KiB
[ebuild  N     ] app-text/po4a-0.47-r1::gentoo  USE="{-test}" LINGUAS="-af -ca -cs -da -de -eo -es -et -eu -fr -hr -id -it -ja -kn -ko -nb -nl -pl -pt -pt_BR -ru -sl -sv -uk -vi -zh_CN -zh_HK" 2,334 KiB

How can it need these packages all of a sudden given that funtoo is running without them right now? 

[nrc]

I assume that you're only showing the "N" (new) items from the list. The 'e' option "Reinstalls target atoms and their entire deep dependency  tree."  If you have packages that were installed without the -D option to pull in deep dependencies they're now going to be pulled in as new.

[mauricev]

The new ones refer to packages that are not present on the system, no? That means the stage3 tarball is missing all these packages, no? How does the system function without them?

[Oleg Vinichenko]

it's because those are likely build dependency which are needed only at build time. to me, this list looks like it's a dependency list for a genkernel and it's deps pulled in. to tell for sure, add --tree to emerge arguments. this does not look bad to me.