Operating system: Linux-5.3.0-20-generic-x86_64-with-Ubuntu-18.04-bionic 64 Bits
Graphics card: GeForce GTX 1080/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 440.26
Broken: version: 2.82 (sub 1), branch: master (modified), commit date: 2019-11-26 05:28, hash: rB75e85f1c9f1e
Short description of error
Delete default cube and add a grid.
Go into edit mode and select 4 faces to make a square selection. (Note it doesn't crash if you select a single face or a line of faces)
Do an inset.
Open properties and check Offset Relative.
Now adjust Depth.
In 2.81 I get weird geometry as pictured, but in my master debug build it crashes with an assert. See attached backtrace.