ibstdc++.so.6:version 'GLIBCXX_3.4.15' not found

How to get GLIBCXX_3.4.15 ?

I used to get the following error

libstdc++.so.6 version 'glibcxx_3.4.15 not found required by compiz, but

In my terminal if i type the following command its showedd 4.6.3

1)gcc --version---->4.6.3

but

2)strings /opt/quartus/linux/libstdc++so.6 | grep GLIBC

GLIBCXX_3.4.

GLIBCXX_3.4.1

GLIBCXX_3.4.2

GLIBCXX_3.4.3

GLIBCXX_3.4.4

GLIBCXX_3.4.5

GLIBCXX_3.4.6

GLIBCXX_3.4.7

GLIBCXX_3.4.8

GLIBCXX_3.4.9

GLIBCXX_2.0

GLIBCXX_2.2

GLIBCXX_2.3

GLIBCXX_2.1.3

GLIBCXX_2.1.2

GLIBCXX_FORCE_NEW.

It showing this much only , how to solve?

Thanks,

Alex.