These are the packages that would be fetched, in order:

Calculating dependencies  
 * IMPORTANT: 1 news items need reading for repository 'gentoo'.
 * Use eselect news read to view new items.

........ ....... done!
[ebuild   R    ] dev-lang/python-exec-2.4.4:2::gentoo  PYTHON_TARGETS="(jython2_7) (pypy) (pypy3) (python2_7) (python3_4) (python3_5) (python3_6%*)" 0 KiB
[ebuild     U  ] dev-util/boost-build-1.62.0-r1::gentoo [1.56.0::gentoo] USE="-examples -python {-test}" PYTHON_TARGETS="python2_7" 0 KiB
[ebuild  r  U  ] dev-libs/boost-1.62.0-r1:0/1.62.0::gentoo [1.56.0-r1:0/1.56.0::gentoo] USE="icu nls python threads -context -debug -doc (-mpi) -static-libs -tools" ABI_X86="(64) -32 (-x32)" PYTHON_TARGETS="python2_7 python3_4 (-python3_5)" 0 KiB
[ebuild  rR    ] dev-libs/librevenge-0.0.4::gentoo  USE="-doc {-test}" ABI_X86="(64) -32 (-x32)" 0 KiB
[ebuild  rR    ] dev-util/mdds-1.2.2:1/1.2::gentoo  USE="-doc -valgrind" 0 KiB
[ebuild  rR    ] dev-libs/libixion-0.11.1:0/0.11::gentoo  USE="-python -static-libs" PYTHON_SINGLE_TARGET="python3_4 (-python3_5)" PYTHON_TARGETS="python3_4 (-python3_5)" 0 KiB
[ebuild  rR    ] dev-libs/liborcus-0.11.2:0/0.11::gentoo  USE="spreadsheet-model -python -static-libs -tools" PYTHON_SINGLE_TARGET="python3_4 (-python3_5)" PYTHON_TARGETS="python3_4 (-python3_5)" 0 KiB
[ebuild  rR    ] net-libs/nghttp2-1.10.0:0/1.14::gentoo  USE="cxx threads xml -debug -hpack-tools -jemalloc (-libressl) -static-libs {-test} -utils" ABI_X86="(64) -32 (-x32)" 0 KiB
[ebuild  r  U  ] dev-lang/ocaml-4.04.0:0/4.04.0::gentoo [4.02.3:0/4.02.3::gentoo] USE="X ncurses ocamlopt -emacs -flambda% -latex -xemacs" 0 KiB
[ebuild  rR    ] dev-lang/ocaml-4.02.3:0/4.02.3::gentoo  USE="X ncurses ocamlopt -emacs -latex -xemacs" 0 KiB
[ebuild  r  U  ] dev-ml/camlp4-4.04_p1:0/4.04_p1::gentoo [4.02.1_p3:0/4.02.1_p3::gentoo] USE="ocamlopt" 0 KiB
[ebuild  rR    ] media-libs/vigra-1.9.0::gentoo  USE="fftw hdf5 jpeg openexr png python tiff -doc {-test}" PYTHON_TARGETS="python2_7" 0 KiB
[ebuild  rR    ] dev-ml/lablgl-1.05-r1:0/1.05::gentoo  USE="glut ocamlopt -doc -tk" 0 KiB
[ebuild  rR    ] dev-cpp/libcmis-0.5.2_pre20160820:0.5::gentoo  USE="-man -static-libs {-test}" 0 KiB
[ebuild  rR    ] app-office/libreoffice-5.2.3.3-r1::gentoo  USE="branding cups dbus gtk java postgres (-aqua) -bluetooth (-coinmp) -collada -debug -eds (-firebird) -gltf -gnome -googledrive -gstreamer -gtk3 -jemalloc -kde (-libressl) -mysql -odk -pdfimport -quickstarter (-telepathy) {-test} -vlc" LIBREOFFICE_EXTENSIONS="-nlpsolver -scripting-beanshell -scripting-javascript -wiki-publisher" PYTHON_SINGLE_TARGET="python2_7 -python3_4 (-python3_5)" PYTHON_TARGETS="python2_7 python3_4 (-python3_5)" 0 KiB
[ebuild  rR    ] media-gfx/enblend-4.1.3-r1::gentoo  USE="openmp -debug -doc -gpu -image-cache" 0 KiB
[ebuild  rR    ] media-gfx/luminance-hdr-2.4.0::gentoo  USE="openmp -fits {-test}" CPU_FLAGS_X86="sse2" LINGUAS="de -cs -es -fi -fr -hi -hu -id -it -pl -ro -ru -sk -tr -zh" 0 KiB
[ebuild  rR    ] media-gfx/hugin-2015.0.0-r1::gentoo  USE="lapack sift -debug -python" LINGUAS="de en_GB -ca@valencia -ca_ES -cs_CZ -da -es -eu -fi -fr -hu -it -ja -nl -pl -pt_BR -ro -ru -sk -sv -zh_CN -zh_TW" PYTHON_SINGLE_TARGET="python2_7 -python3_4" PYTHON_TARGETS="python2_7 python3_4" 0 KiB
[ebuild  rR    ] media-sound/clementine-1.3.1-r5::gentoo  USE="cdda dbus mtp projectm udisks -amazoncloud -box -debug -dropbox -googledrive -ipod -lastfm -mms -moodbar -pulseaudio -skydrive {-test} -vkontakte -wiimote" LINGUAS="de en_GB nb -af -ar -be -bg -bn -br -bs -ca -cs -cy -da -el -en_CA -eo -es -et -eu -fa -fi -fr -ga -gl -he -he_IL -hi -hr -hu -hy -ia -id -is -it -ja -ka -kk -ko -lt -lv -mr -ms -my -nl -oc -pa -pl -pt -pt_BR -ro -ru -si_LK -sk -sl -sr -sr@latin -sv -te -tr -tr_TR -uk -uz -vi -zh_CN -zh_TW" 0 KiB

Total: 19 packages (4 upgrades, 15 reinstalls), Size of downloads: 0 KiB

!!! Multiple package instances within a single package slot have been pulled
!!! into the dependency graph, resulting in a slot conflict:

dev-lang/ocaml:0

  (dev-lang/ocaml-4.04.0:0/4.04.0::gentoo, ebuild scheduled for merge) pulled in by
    >=dev-lang/ocaml-4.04_beta:=[ocamlopt?] required by (dev-ml/camlp4-4.04_p1:0/4.04_p1::gentoo, ebuild scheduled for merge)
    ^^               ^^^^^^^^^                                                                                                

  (dev-lang/ocaml-4.02.3:0/4.02.3::gentoo, ebuild scheduled for merge) pulled in by
    <dev-lang/ocaml-4.02.3-r1 required by (dev-ml/camlp4-4.04_p1:0/4.04_p1::gentoo, ebuild scheduled for merge)
    ^               ^^^^^^^^^                                                                                   


It may be possible to solve this problem by using package.mask to
prevent one of those packages from being selected. However, it is also
possible that conflicting dependencies exist such that they are
impossible to satisfy simultaneously.  If such a conflict exists in
the dependencies of two different packages, then those packages can
not be installed simultaneously.

For more information, see MASKED PACKAGES section in the emerge man
page or refer to the Gentoo Handbook.


The following packages are causing rebuilds:

  (dev-lang/ocaml-4.04.0:0/4.04.0::gentoo, ebuild scheduled for merge) causes rebuilds for:
    (dev-ml/lablgl-1.05-r1:0/1.05::gentoo, ebuild scheduled for merge)
    (dev-ml/camlp4-4.04_p1:0/4.04_p1::gentoo, ebuild scheduled for merge)
  (dev-libs/boost-1.62.0-r1:0/1.62.0::gentoo, ebuild scheduled for merge) causes rebuilds for:
    (dev-cpp/libcmis-0.5.2_pre20160820:0.5/0.5::gentoo, ebuild scheduled for merge)
    (media-sound/clementine-1.3.1-r5:0/0::gentoo, ebuild scheduled for merge)
    (media-gfx/luminance-hdr-2.4.0:0/0::gentoo, ebuild scheduled for merge)
    (dev-util/mdds-1.2.2:1/1.2::gentoo, ebuild scheduled for merge)
    (media-gfx/hugin-2015.0.0-r1:0/0::gentoo, ebuild scheduled for merge)
    (media-gfx/enblend-4.1.3-r1:0/0::gentoo, ebuild scheduled for merge)
    (app-office/libreoffice-5.2.3.3-r1:0/0::gentoo, ebuild scheduled for merge)
    (dev-libs/liborcus-0.11.2:0/0.11::gentoo, ebuild scheduled for merge)
    (dev-libs/libixion-0.11.1:0/0.11::gentoo, ebuild scheduled for merge)
    (net-libs/nghttp2-1.10.0:0/1.14::gentoo, ebuild scheduled for merge)
    (dev-libs/librevenge-0.0.4:0/0::gentoo, ebuild scheduled for merge)
    (media-libs/vigra-1.9.0:0/0::gentoo, ebuild scheduled for merge)
  (dev-ml/camlp4-4.04_p1:0/4.04_p1::gentoo, ebuild scheduled for merge) causes rebuilds for:
    (dev-ml/lablgl-1.05-r1:0/1.05::gentoo, ebuild scheduled for merge)

>>> Fetching (1 of 19) dev-lang/python-exec-2.4.4::gentoo

 * python-exec-2.4.4.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...        [ ok ]

>>> Fetching (2 of 19) dev-util/boost-build-1.62.0-r1::gentoo
 * boost_1_62_0.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...             [ ok ]

>>> Fetching (3 of 19) dev-libs/boost-1.62.0-r1::gentoo
 * boost_1_62_0.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...             [ ok ]

>>> Fetching (4 of 19) dev-libs/librevenge-0.0.4::gentoo
 * librevenge-0.0.4.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...          [ ok ]

>>> Fetching (5 of 19) dev-util/mdds-1.2.2::gentoo
 * mdds-1.2.2.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...               [ ok ]

>>> Fetching (6 of 19) dev-libs/libixion-0.11.1::gentoo
 * libixion-0.11.1.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...           [ ok ]

>>> Fetching (7 of 19) dev-libs/liborcus-0.11.2::gentoo
 * liborcus-0.11.2.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...           [ ok ]

>>> Fetching (8 of 19) net-libs/nghttp2-1.10.0::gentoo
 * nghttp2-1.10.0.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...            [ ok ]

>>> Fetching (9 of 19) dev-lang/ocaml-4.04.0::gentoo
 * ocaml-4.04.0.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...              [ ok ]
 * ocaml-patches-8.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...          [ ok ]

>>> Fetching (10 of 19) dev-lang/ocaml-4.02.3::gentoo
 * ocaml-4.02.3.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...              [ ok ]
 * ocaml-patches-7.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...          [ ok ]

>>> Fetching (11 of 19) dev-ml/camlp4-4.04_p1::gentoo
 * camlp4-4.04_p1.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...            [ ok ]

>>> Fetching (12 of 19) media-libs/vigra-1.9.0::gentoo
 * vigra-1.9.0-src.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...           [ ok ]

>>> Fetching (13 of 19) dev-ml/lablgl-1.05-r1::gentoo
 * lablgl-1.05.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...               [ ok ]

>>> Fetching (14 of 19) dev-cpp/libcmis-0.5.2_pre20160820::gentoo
 * libcmis-0.5.2_pre20160820.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ... [ ok ]

>>> Fetching (15 of 19) app-office/libreoffice-5.2.3.3-r1::gentoo
 * libreoffice-branding-gentoo-0.8.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...     [ ok ]
 * libreoffice-5.2.3.3.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...       [ ok ]
 * libreoffice-help-5.2.3.3.tar.xz SHA256 SHA512 WHIRLPOOL size ;-) ...  [ ok ]
 * ce12af00283eb90d9281956524250d6e-xmlsec1-1.2.20.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...                     [ ok ]
 * 17410483b5b5f267aa18b7e00b65e6e0-hsqldb_1_8_0.zip SHA256 SHA512 WHIRLPOOL size ;-) ...                [ ok ]

>>> Fetching (16 of 19) media-gfx/enblend-4.1.3-r1::gentoo
 * enblend-enfuse-4.1.3.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...      [ ok ]

>>> Fetching (17 of 19) media-gfx/luminance-hdr-2.4.0::gentoo
 * luminance-hdr-2.4.0.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...      [ ok ]

>>> Fetching (18 of 19) media-gfx/hugin-2015.0.0-r1::gentoo
 * hugin-2015.0.0.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...           [ ok ]

>>> Fetching (19 of 19) media-sound/clementine-1.3.1-r5::gentoo
 * clementine-1.3.1.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...          [ ok ]