LibreOffice File not recognized: File truncated

Problem :

I have the following problem when I build libreoffice. I've tried to delete it and emerge it an other time
but without success :

[ build CXX ] stoc/source/corereflection/crarray.cxx
[ build CXX ] stoc/source/corereflection/crbase.cxx
[ build CXX ] stoc/source/corereflection/crcomp.cxx
[ build CXX ] stoc/source/corereflection/crefl.cxx
[ build CXX ] stoc/source/corereflection/crenum.cxx
[ build CXX ] stoc/source/corereflection/criface.cxx
[ build LNK ] Library/reflection.uno.so
/var/tmp/portage/app-office/libreoffice-3.6.4.3/work/libreoffice-core-3.6.4.3/workdir/unxlngi6.pro/CxxObject/stoc/source/corereflection/crenum.o: file not recognized: File truncated
collect2: ld returned 1 exit status
make[2]: *** [/var/tmp/portage/app-office/libreoffice-3.6.4.3/work/libreoffice-core-3.6.4.3/workdir/unxlngi6.pro/LinkTarget/Library/reflection.uno.so] Error 1

-----------------------------------------------------------------------
        Oh dear - something failed during the build - sorry !
  For more help with debugging build errors, please see the section in:
            http://wiki.documentfoundation.org/Development

  internal build errors:

ERROR: error 512 occurred while making /var/tmp/portage/app-office/libreoffice-3.6.4.3/work/libreoffice-core-3.6.4.3/stoc/prj

 it seems that the error is inside 'stoc', please re-run build
 inside this module to isolate the error and/or test your fix:

build_error.log should contain the captured output of the failed module(s)

-----------------------------------------------------------------------
To rebuild a specific module:

make stoc.clean # optional
make stoc

when the problem is isolated and fixed, re-run 'make'
make[1]: *** [build-packimages] Error 1
make[1]: Leaving directory `/var/tmp/portage/app-office/libreoffice-3.6.4.3/work/libreoffice-core-3.6.4.3'
make: *** [build] Error 2
 * ERROR: app-office/libreoffice-3.6.4.3 failed (compile phase):
 *   (no error message)
 *
 * Call stack:
 *     ebuild.sh, line  93:  Called src_compile
 *   environment, line 8981:  Called die
 * The specific snippet of code:
 *       make build || die
 *
 * If you need support, post the output of `emerge --info '=app-office/libreoffice-3.6.4.3'`,
 * the complete build log and the output of `emerge -pqv '=app-office/libreoffice-3.6.4.3'`.
!!! When you file a bug report, please include the following information:
GENTOO_VM=  CLASSPATH="" JAVA_HOME="/etc/java-config-2/current-system-vm"
JAVACFLAGS="" COMPILER=""
and of course, the output of emerge --info
 * The complete build log is located at '/var/tmp/portage/app-office/libreoffice-3.6.4.3/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/app-office/libreoffice-3.6.4.3/temp/environment'.
 * Working directory: '/var/tmp/portage/app-office/libreoffice-3.6.4.3/work/libreoffice-core-3.6.4.3'
 * S: '/var/tmp/portage/app-office/libreoffice-3.6.4.3/work/libreoffice-core-3.6.4.3'

Solution :

You just have to delete data in your cache directory.For example, if you have a CCache, it's probably set in make.conf with CCACHE_DIR="/var/tmp/ccache".
A good explanation about reason could be found on this blog http://fossdev.blogspot.fr/2011/08/file-not-recognized-file-truncated.html