Thanks for the report, but we need a simplified file for this. Your file has a hidden avatar in the second layer, multiple textures, ... the ideal is to isolate the problem in a file as simple as possible. And no need to rar the file. Blender allows you to save a compressed file instead.

@Mai Lavelle (maiself) the crash is on kernel_compat_cpu.h, is that something related to split kernel? You can see my backtrace here: P469 I get it to crash if I cancel it right after baking starts. It's fairly easy to reproduce with this big file.

Thanks for your answer , here is the simplified file{F572920}. i did some test, i have seen that the problem maybe is in transparency of the leaves, because if i bake in cycles the stairs it crashes if in the leaves there is a material with transpaency, infact if i put on the leaves the basic materials it works, instead if i leave the transparent material (i need it for the shadows of the leaves on the wood) and i use Gpu , then it works.
But if i use 2.77a version of blender it works also with the CPU and never crashes, this is weird :///

The bug in the original report was fixed by rB8c5826f59a37: Fix T50698: Cycles baking artifacts with transparent surfaces. I believe, can be tested with latest builds from https://builder.blender.org/download/. It no longer crashes for me in latest builds while it was still crashing in 2.78c.

The crash when cancelling the bake is a different issue, where it still tries baking with incomplete data even if scene sync and update is cancelled, which I've fixed now.