The GNU Standard c++ library libstdc++.so.5 is a core library for CentOS system. Most of the operating systems comes with a version of libstdc++ in sync with architecture ( i.e., 32 bit or 64 bit system ) of OS. That is 64 bit OS have 64 bit libstdc++.
However to install various other tools and compiler like intel compiler, on a 64 bit system, we require to have 32 bit compatible version of libstdc++ as well. Otherwise the installation will fail.
To get around this problem, download compat-libstdc++ for your os and install. This will install 32 bit compatible version of libstdc++ on 64 bit system.
On CentOS 6.3
1. download compat-libstdc++ from here
$ yum install compat-libstdc++-33-3.2.3-69.el6.i686.rpm
Find 32 bit libstdc++ at /usr/lib/ on CentOS
Find 64 bit libstdc++ at /usr/lib64/ on Cent OS
Use below command to ensure which one is 32 bit and which one is 64 bit.
$ readelf -h /usr/lib64/libstdc++.so.5