is_local() on null gptr

[Dan Bonachea]

bool result = global_ptr<T>(NULL).is_local()

What should this return?

This is ambiguous in the current spec.

Possible resolutions include:

1. Add a precondition forbidding this method call on null global pointers
2. Add text guaranteeing a false return for null global pointers
3. Add text guaranteeing a true return for null global pointers

Note that .1 and .2 also imply that global_ptr<T>(NULL).local() is prohibited, which seems overly restrictive and likely to add branches in code that is written to localize (non-remote) gptrs without regard to their specific value (or null-ness). FWIW, UPC allows down-casts of pointer-to-shared NULL to pointer-to-local NULL, without no special care required.

I vote for resolution .3

[Amir Kamil]

Fixed in 56857b1, in favor of always returning true.