On all Junos Evolved platforms, when an app is closing (like app restart, node restart,..), evo-aftmand-bt process crash might be observed. 

The core files could be seen by executing CLI command "show system core-dumps".

This can be triggered node restart or app restart of any app.

App can access shared objects after distributord has dropped the reference of the app (but before app got the disconnect notification).

This can lead to a crash because the shared object might have changed. 

Generally app restart happen very rarely, if not manually initiated & hence this PR is also rare.

https://prsearch.juniper.net/problemreport/PR1719739