I faced the subj error after updating Perl package. It appears, Scalar::Util package is shipped with C-compiled modules which are not properly updated by yum. The workaround is manual package reinstalling:

wget http://search.cpan.org/CPAN/authors/id/G/GB/GBARR/Scalar-List-Utils-1.23.tar.gz && \
tar zxvf Scalar-List-Utils-1.23.tar.gz && \
cd Scalar-List-Utils-1.23 && \
perl Makefile.PL && \
make test install && \