I have a Nexus 6P API23 emulator downloaded on my Ubuntu 15.10 PC. When I try to launch it, it fails and a dialog box pops up and says:
(AVD config: Nexus 6P API 23
Entering the following in the terminal (Ctrl-Alt-T) solved this for me:
cd $Android/Sdk/tools/lib64/libstdc++
mv libstdc++.so.6 libstdc++.so.6.bak
ln -s /usr/lib64/libstdc++.so.6
This apparently creates a symlink. This solution was taken from Line #23 of https://code.google.com/p/android/issues/detail?id=197254#c23.
You may need to change the paths to the files depending on your installation (i.e. the original used the path ANDROID_HOME/android-sdk-linux_x86/ whereas my installation was just Android/Sdk/).