I already had the same problem in the recent past while I was trying to compile the little tool which I wrote for the old machine for which I had not any compiler. I compiled it on the up to date machine, and that binary required at least GLIBC 2.14 in order to run it.
By making the dump of a binary with xxd, I found below lines :
5f64 736f 5f68 616e 646c 6500 6d65 6d63 _dso_handle.memc
7079 4040 474c 4942 435f 322e 3134 005f py@@GLIBC_2.14._
So I simply replaced my memcpy calls in the code by the call to a home-made memcpy, and a dependency with a glibc 2.14 magically disappeared.
I hope the above solution helps you in resolving your issue.