The build of the package sys-boot/grub-2.00_p5107-r2:2 failed with the following error message: Can't locate Locale/gettext.pm in @INC (@INC contains: /etc/perl /usr/local/lib64/perl5/5.16.3/x86_64-linux /usr/local/lib64/perl5/5.16.3 /usr/lib64/perl5/vendor_perl/5.16.3/x86_64-linux /usr/lib64/perl5/vendor_perl/5.16.3 /usr/local/lib64/perl5 /usr/lib64/perl5/vendor_perl /usr/lib64/perl5/5.16.3/x86_64-linux /usr/lib64/perl5/5.16.3 .) at /usr/bin/help2man line 28. BEGIN failed--compilation aborted at /usr/bin/help2man line 28. make[2]: *** [grub-mkrescue.1] Error 2 This missing file (normaly located under /usr/lib64/perl5/vendor_perl/5.12.4/x86_64-linux-thread-multi/Locale/gettext.pm) belongs to the package 'dev-perl/Locale-gettext'. In the appropriate ebuild sys-apps/help2man-1.40.11 the dependency to dev-perl/Locale-gettext is set, but only, if the USE flag elibc_glibc is set. But I cannot find any information about this USE flag: 0 samara:~ # quse -D elibc_glibc 0 samara:~ # And in the pretend output of emerging sys-apps/help2man this USE flag is not shown: 0 samara:/ # emerge -pv1 sys-apps/help2man These are the packages that would be merged, in order: Calculating dependencies... done! [ebuild R ] sys-apps/help2man-1.40.11 USE="nls" 187 kB Total: 1 package (1 reinstall), Size of downloads: 187 kB 0 samara:~ # So my guess is, that in the ebuild files of sys-apps/help2man the dependency to dev-perl/Locale-gettext is set incorrectly (in all other ebuilds of sys-apps/help2man there is the same failure).
You need to run "perl-cleaner --all" per the post-install messages on your recent upgrade to perl-5.16. *** This bug has been marked as a duplicate of bug 41124 ***