Why is perl EV not installed?

Question

Perl

Installing perl EV on CentOS

wget http://cpan.rinet.ru/authors/id/M/ML/MLEHMANN/EV-4.18.tar.gz
tar xzf EV-4.18.tar.gz
cd EV-4.18
perl Makefile.PL
make install clean

Strange errors occur at step 4 , what could be the problem?
I try to run dklab_realplexor:

[[email protected] dklab_realplexor]# cd /opt/dklab_realplexor/
[[email protected] dklab_realplexor]# ./dklab_realplexor.pl
Error: EV library is not found in your system:
http://search.cpan.org/~mlehmann/EV-3.9/EV.pm
You must install EV, e.g.:
# yum install gcc
# perl -MCPAN -e "install EV"
  - or -
# apt-get install gcc
# perl -MCPAN -e "install EV"

Answer 1

These are not errors, but compiler warnings. Do not pay attention to them if the tests pass without errors:
make & make test & make install