Strange type of crash

Crashes like this in memory management code (e.g., malloc) are usually caused by writing past the beginning or end of an array. They can also be caused other ways, such as reusing memory that has been freed or changing the size of a struct or class and not recompiling all code that uses that struct or class.

In cases like this, it's often a good idea to clean the build environment (Product -> Clean build folder...) and see if that resolves the problem. If not, it's possibly a buffer overrun or underrun.

In this particular case, it looks like a bezier curve is being drawn. You might want to make sure that you are not writing to positions before the beginning of after the end of your control point array.

The memory corruption may also be caused by other threads, and may not be directly related to the thread that is crashing. More information about how to trigger this crash would be needed in order to be more specific.