swift

0d4980e0 - DeadFunctionElimination: keep global variables alive which are referenced from another global

DeadFunctionElimination: keep global variables alive which are referenced from another global Fixes a compiler crash in case a private global is only reference from another global variable, for example: ``` private var g1 = 27 let g2 = UnsafePointer(&g1) ``` rdar://117189962