System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: NVIDIA Quadro P5200/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 466.11

Blender Version
Broken: version: 3.0.0 Alpha, branch: master, commit date: 2021-06-07 22:19, hash: rBef5a362a5b24
Worked: (newest version of Blender that worked as expected)

Short description of error
Using negative values into the Count Input socket of the Line Mesh Primitive node crashes Blender (like in the image attached)

Exact steps for others to reproduce the error

1. Default factory reset file
2. Add a Geometry Node modifier to the default cube, create and conect a Line Mesh Primitive node to the Output node.
3. Conect a Value Node to the Count Input and change it to a negative value.

In the image below the Value node is 4. When the Value is negative Blender crashes. I checked this with other Mesh Primitive Nodes but didn't get more crashes (it seems it only crash with the Line Primitive Count Input socket)