Why are the libstdc++.so.6.0.17 shipped with R2014a and R2014b different?

It seems that if they have the same complete version# then they should be identical, but they are not.

So, when I use MATLAB Coder to generate a dll, it may or may not work depending on which libstdc++.so.6.0.17 is installed on the target system. And, changing it to a different one may break something else.

Is there a good way around this?