I know this question may not be directly related to Blender, but maybe it does! Please correct if I am wrong!
I can build and step debugging on Blender 2.78 prior to Xcode 8.1, but something get broken since Xcode 8.1, my situation is as follows:
- build and run blender build from Xcode, following the directions in : https://wiki.blender.org/index.php/Dev:Doc/Building_Blender/Mac
- set break point on run_cpu(), and read_node()
- run blender build, select cycles render and select render mode
- it should stop at both breakpoints prior to Xcode 8.1, while not stop at read_node() since 8.1
My environment is MacOS Sierra. For completness, the checkout commit is cf8f6d1 from blender git.