Operating system: Mac OS High Sierra 10.13.5
Graphics card: Radeon Pro 560 4GB (Blender didn't detect it, for what that's worth)
I have a Windows bot at home I can check this for later.
version: 2.80 (sub 44), branch: blender2.7, commit date: 2019-02-15 14:15, hash: faa255c0a4e4, type: Release
build date: 2019-02-15, 16:23:20
This is a pretty specific error. Create an array modifier with an end cap, start cap, or both. Now, enable merge in the array modifier, turn on edit mode, and set the modifier to show in the edit cage (it's the fourth button in the modifier settings, at the top). Now, enter edit mode and move a vertex to merge with the end/start cap object. Blender immediately crashes to desktop.
From the .blend file attatched, just enter edit mode and move some verts.