Factsheet
It turns out I was just not familiar enough with apt-get. I managed to install the necessary glibc version by issuing the following command:
apt-get install libc-bin=2.13-38+deb7u4 libc6=2.13-38+deb7u4
I even downgraded it and everything works okay. Core dump analysis works now.
I wouldn't install it, but unpack it in some work directory and refer to it via LD_LIBRARY_PATH. Downgrading your libc6 package can be quite problematic.
Your customer should be able to supply you with their libc6 version. It might, however, be advisable to use the libc6-dbg package which includes debug symbols. Unfortunately the 7u4 version is an older one and not available anymore.
Basically im trying to run a game but it requires at least glibc 2.38 but it seems debian only offers 2.36 at the moment. Any way i can get a newer vesion of it?
EDIT: ended up just downloading the windows version of the game and running it with wine, im an idiot and thought i was having a problem with the sound when i first downloaded, that's why i tried the linux binary, but when i ran it with wine again i found out that the game came muted by default and that i had to press + to get the volume up