lcdf-typetools conflicts with openmpi in Gentoo

Question

here is the output after running nice -n 15 emerge -abvuDN --quiet-build=y --autounmask-write --ignore-built-slot-operator-deps=y --backtrack=50 world

 * Error: The above package list contains packages which cannot be 
 * installed at the same time on the same system. 

  (app-text/lcdf-typetools-2.100::gentoo, ebuild scheduled for merge) pulled in by 
    >=app-text/lcdf-typetools-2.92[kpathsea] required by (app-text/texlive-2012::gentoo, installed) 

  (sys-cluster/openmpi-1.4.3::gentoo, ebuild scheduled for merge) pulled in by 
    sys-cluster/openmpi[cxx?,fortran?,romio?,threads?] (sys-cluster/openmpi[cxx,fortran,romio]) require 
    sys-cluster/openmpi[cxx] required by (dev-libs/boost-1.55.0-r1::gentoo, ebuild scheduled for merge) 

Then I have masked lcdf-typetools and ran the same update command, it shows.

* Error: The above package list contains packages which cannot be 
 * installed at the same time on the same system. 

  (sys-cluster/openmpi-1.4.3::gentoo, ebuild scheduled for merge) pulled in by 
    sys-cluster/openmpi[cxx?,fortran?,romio?,threads?] (sys-cluster/openmpi[cxx,fortran,romio]) required by (virtual/mpi-2.0-r3::gentoo, ebuild scheduled for merge) 
    sys-cluster/openmpi[cxx] required by (dev-libs/boost-1.55.0-r1::gentoo, ebuild scheduled for merge) 

  (app-text/lcdf-typetools-2.104::gentoo, ebuild scheduled for merge) pulled in by 
    >=app-text/lcdf-typetools-2.92[kpathsea] required by (app-text/texlive-2012::gentoo, installed) 


For more information about Blocked Packages, please refer to the following 
section of the Gentoo Linux x86 Handbook (architecture is irrelevant): 

http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?full=1#blocked 


The following mask changes are necessary to proceed: 
 (see "package.unmask" in the portage(5) man page for more details) 
# required by app-text/texlive-2012 
# required by @selected 
# required by @world (argument) 
# /etc/portage/package.mask/a: 
#=sci-mathematics/petsc-3.5.1 
#=app-text/poppler-0.24.5 
#=app-text/poppler-0.24.5 
#net-libs/webkit-gtk 
#<=x11-drivers/nvidia-drivers-340.46 
=app-text/lcdf-typetools-2.104 

NOTE: The --autounmask-keep-masks option will prevent emerge 
      from creating package.unmask or ** keyword changes. 

how can I sort out this conflict? It has been there for many days.

updates:

I have tried to unmerge both atoms that requires openmpi, but it is still been pulled over by other atoms.

notes

openmpi is very important for me, there is no compromise for not installing it. lcdf-typetools is pulled over by texlive-2012, which is also one of the key packages I use reguarly

Answer 1

You should emerge one of the packages that cannot be installed at the same time.

emerge app-text/lcdf-typetools

or

emerge sys-cluster/openmpi

Then try updating your whole system.