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Pitfalls

1. Multiple threads of control can be executing on one processor object at any one time, since anyone with a global pointer to a processor object can perform an RPC. Use atomic and sync to prevent dangerous sharing.

2. The destructor for a processor object is just another member function of that object. It can be running concurrently with other threads on the processor object, and will not wait for those other threads to finish before deallocating the processor object. In CC++ it is bad style to finish a computation when all processor objects have not been deallocated. The system will try to deallocate those processor objects left by the user. The system is not always able to do this, and in CC++ the consequences of an undeallocated processor object are significant: a process left running, wasting processor time and resources. That process may even exist on another machine. Ending a computation with exit() from any processor object guarantees that all processor objects are deleted, while ending it with abort() will not. Killing a single process in the computation, for instance using the UNIX kill command, will not terminate the entire computation.

In addition, the current implementation has the following pitfalls:

1. The syntax delete [] to delete an array of pointers cannot be used with an array of pointers to processor objects.

2. CC++ defines a function, called the entry function, for each type to handle RPCs to objects of that type. This function is automatically generated by the compiler. When compiling many modules into one executable, the same type can be declared many times. If the entry function is defined in each module, a link-time error will result. Because of this, CC++ defines the entry function for a type at the point of the first non-inline non-constructor member function of that type. If there are no non-inline non-constructor members of a type, you can force entry functions to be defined at the point of type declaration by using the compiler option +ee1.